Journal articles: 'Semi-solid phase'

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Uhlén, Mathias, Thomas Hultman, Johan Wahlberg, Joakim Lundeberg, Staffan Bergh, Bertil Petterson, Anders Holmberg, Stefan Ståhl, and Tomas Moks. "Semi-automated solid-phase DNA sequencing." Trends in Biotechnology 10 (1992): 52–55. http://dx.doi.org/10.1016/0167-7799(92)90169-v.

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Hu, Xiao Gang, Qiang Zhu, Helen V. Atkinson, Min Luo, Fan Zhang, and Wen Ying Qu. "Application of Multiphase Modelling in Semi-Solid Die Casting: Blister Prediction." Solid State Phenomena 256 (September 2016): 139–45. http://dx.doi.org/10.4028/www.scientific.net/ssp.256.139.

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One-phase modelling is widely used as an optimization and design tool for semi-solid casting process. By this approach, semi-solid alloy is taken as a homogeneous fluid and flow behaviours are represented by using the rheological properties of the mixture. A single set of conservation equations is solved to simulate the mould filling, without considering the different motilities between the liquid and the solid phase. Therefore, defects due to phase segregation cannot be predicted and particle tracking cannot be carried out. This study is focused on multiphase (i.e. a liquid-particle-air system) modelling during the semi-solid filling process of a thin-walled component. By using this approach, the solid phase is treated as a power law fluid and the phase interactions among the phases are introduced for the semi-solid alloy system. Practical semi-solid die casting is carried out for verification of phase segregation. The final distribution of air is calculated and proved by practical blistering examination. The simulation results are verified to be accurate in a reasonable range, indicating an approach for modelling semi-solid filling including the formation (and avoidance) of blisters.

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Liu, Zhao Ming, Xin Wang, Ying Bo Zhang, and Hong Gao. "Effects of Semi-Solid Isothermal Treatments on Microstructures of Quasicrystal Reinforced AZ91 Alloys." Advanced Materials Research 430-432 (January 2012): 551–55. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.551.

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The as-cast and semi-solid microstructures of quasicrystal reinforced AZ91 alloys were investigated. The results show that the main phases of as-cast AZ91ZY1 and AZ91ZY2 alloys are all α-Mg, I-phase, Mg17Al12 and Al2Y phase. The grain boundary phases contents increase with increasing Y and Zn contents. The better semi-solid processing technological parameters of AZ91ZY1 and AZ91ZY2 alloys are 580 °C, 30 min and 560 °C, 30 min respectively. The better semi-solid processing temperature of AZ91ZY2 alloy is lower than the one of AZ91ZY1 alloy is mainly attributed to the higher contents of the grain boundary phases in the AZ91ZY2 alloy.

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Liu, Zheng, and Xiao Mei Liu. "Study on Fractal Characteristics of Primary Phase Morphology in Semi-Solid A356 Alloy." Advanced Materials Research 139-141 (October 2010): 653–56. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.653.

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Semi-solid A356 slurry was prepared by compound process, and the fractal characteristic of primary phase morphology was researched. The fractal dimensions of primary phase morphology in semi-solid A356 alloy were calculated by the calculating program written to calculate the fractal dimensions of box-counting in the imagine of morphology of semi-solid primary phase in A356 alloy. The results indicated that the primary phase morphology in semi-solid A356 prepared by compound process is characterized by fractal dimension, and the primary phase morphology prepared by the different technology parameters had different fractal dimensions. The primary phase morphology at the different position of ingot had the different fractal dimensions, which reflected the effect of solidified conditions at different position in the same ingot on the morphology of semi-solid primary phase

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Li, Nai Yong, Han Xiao, Chi Xiong, De Hong Lu, and Rong Feng Zhou. "Microstructure of Semi-Solid Extruded Copper Alloy after Heat Treatment." Solid State Phenomena 285 (January 2019): 146–52. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.146.

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The semi-solid extruded ZCuSn10P1 copper alloy were annealed at different temperatures and time. The influences of heat treatment temperature and holding time on the microstructure of semi-solid ZCuSn10P1 copper alloy were investigated. The results show that with the increase of heat treatment temperature, the morphology of the semi-solid microstructure was improved, the sharp angle around the primary phase α-Cu and the liquid droplets were reduced. With the increase of heat treatment time, the solid-liquid segregation of the semi-solid structure was improved. The average grain size of the solid phase increased with the increasing of the holding time. After heat treatment, the solid solubility of the primary phase α-Cu increased, and the Sn and P elements in the liquid phase continued to diffuse to the primary phase α-Cu. The microstructure of semi-solid copper alloy was the most uniform after heat treatment at 350°C for 120 min.

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Yang, Xiang Jie, Ming Wang, Liang Sheng Ding, Hong Min Guo, and Xu Bo Liu. "Squeeze Casting of Semi-Solid A356 Alloy." Solid State Phenomena 217-218 (September 2014): 436–41. http://dx.doi.org/10.4028/www.scientific.net/ssp.217-218.436.

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the rheo-squeeze casting (Rheo-SQC) combining the rheocasting and the SQC was developed, in which semi-solid slurry was produced by the low superheat pouring with a shearing field (LSPSF) process. The three dimensional morphology of the primary α-Al phase and the rest spacing of slurry prepared by LSPSF process have been reconstructed and visualized, and the microstructures of squeeze cast A356 alloy have been obtained. Based on the three dimensional microstructure reconstructed, their three dimensional characterizations such as solid volume fraction, equivalent diameter of the extracted primary α-Al phase were measured and calculated, and the microstructures of cross section of squeeze cast product were investigated.

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Krchňák, Viktor. "Semi-automated high throughput combinatorial solid-phase organic synthesis." Biotechnology and Bioengineering 61, no. 3 (1999): 135–41. http://dx.doi.org/10.1002/(sici)1097-0290(1998)61:3<135::aid-cc1>3.0.co;2-s.

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Koeune, R., and Jean Philippe Ponthot. "A One Phase Thermomechanical Model for Semi-Solid Thixoforming." Solid State Phenomena 141-143 (July 2008): 629–35. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.629.

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In order to model thixoforming processes, previous papers presented a thermomechanical one-phase modelling. This first version of constitutive model revealed several limitations: the model could not degenerate properly to pure solid or liquid behaviour neither to free solid suspensions. The aim of this paper was to propose solutions to overcome these limitations.

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Kang, Suk Won, Dock Young Lee, and Ki Bae Kim. "Effect of Isothermal Holding Temperature on Globularization of Primary Solid Phase in Multiplex-Type Slurry Cup." Solid State Phenomena 116-117 (October 2006): 239–42. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.239.

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In order to produce a high quality and cost effective part in the rheocasting process for an automobile industry it has been important to develop a slurry-on-demand process, which can manufacture the semi-solid slurry having a fine and globular structure of primary solid phase. The morphology of primary solid phase of semi-solid slurry is coarsened and globularized during an isothermal holding process in a solid-liquid region. Accordingly, in this paper, the microstructural evolution of semi-solid slurry during the isothermal holding at a various temperature in solid-liquid region was investigated to examine a coarsening and globularization behavior of primary solid phase. The semi-solid slurry of Al alloy was produced in a slurry maker using a multiplex-type slurry cup that we developed recently. A size of primary solid phase was the finer at the higher holding temperature, but under a constant holding time a roundness degree of primary solid phase was the lower at the lower holding temperature. Also, a coarsening rate of primary solid phase was not considered to be affected significantly by a holding temperature even though a little lower coarsening rate was obtained at the higher holding temperature.

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Wang, Jia, De Hong Lu, Han Xiao, Rong Feng Zhou, Rong Zhou, and Long Biao Wu. "Effect of Rolling-Remelting SIMA Process on Semi-Solid Microstructure of ZCuSn10 Alloy." Solid State Phenomena 217-218 (September 2014): 418–25. http://dx.doi.org/10.4028/www.scientific.net/ssp.217-218.418.

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Semi-solid billet of ZCuSn10 (Wt%: 88.25Cu, 10.48Sn) alloy is prepared by strain induced melt activated (SIMA) method which including rolling and remelting process. Firstly, ZCuSn10 alloy is casted, and rolling samples are cut from ingot casting. Secondly, the rolling samples are two pass or four pass rolled after holding 15 minutes at 450°C, then samples with 10% and 20% pre-deformation degree are obtained. The remelting samples are cut from pre-deformed samples. Lastly, the remelting samples are reheated up to 850°C or 875°C, water quenching after holding for 15 minutes. Then semi-solid microstructure of ZCuSn10 alloy is prepared. The semi-solid microstructure of ZCuSn10 alloy is observed and compared with annealed microstructure and microstructure of ZCuSn10 alloy directly remelted after casting. The results indicate that semi-solid microstructure of ZCuSn10 alloy by rolling-remelting SIMA process is uniform and fine grain, and spheroidization level of solid particle is well. The optimum semi-solid microstructure is obtained when alloy with pre-deformation 20% is remelted at 875°C for 15 minutes, the average grain diameter is about 75.80μm, shape factor is 1.62, and volume fraction of liquid phase reaches about 17.28%. Pre-deformation process plays a crucial role in grain refinement and spheroidization during SIMA process for preparing the semi-solid ZCuSn10 alloy, as pre-deformation degree and remelting temperature increases, volume fraction of liquid phase increases, the solid particles in semi-solid microstructure are smaller and rounder. The main mechanism of SIMA process preparing semi-solid billet of ZCuSn10 alloy is that pre-deformation breaks dendrites and stores energy of deformation into alloy, and promotes dendrites fusing through remelting process. Meanwhile, liquid phase occupies sharp corners of solid particles by Sn element diffusing from liquid phase into α solid phase, so that fine and uniform and globular α solid particles are gained.

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Peter, Ildiko, Christian Castella, and Mario Rosso. "The Role of Liquid Phase in SSM Processes." Materials Science Forum 884 (January 2017): 93–114. http://dx.doi.org/10.4028/www.scientific.net/msf.884.93.

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The present chapter reports a short history and a state-of-the art of semi-solid techniques, with particular emphasis to the role of the liquid-solid fraction, being the rheological behaviour of the semi-solid slurry crucial and fundamental. The general description, with the related theoretical fundaments, is based on the data available in the recent and the past literature and finally it is integrated with some experimental results of the research carried out by the authors.

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Kang, Suk Won, Ki Bae Kim, Dock Young Lee, Jung-Hwa Mun, and Eui Pak Yoon. "Effect of Pouring Temperature and Holding Time at Semi-Solid Region on the Morphology of Primary Solid Phase in Semi-Solid Slurry." Materials Science Forum 510-511 (March 2006): 782–85. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.782.

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Chigome, Samuel, Godfred Darko, Ulrich Buttner, and Nelson Torto. "Semi-micro solid phase extraction with electrospun polystyrene fiber disks." Analytical Methods 2, no. 6 (2010): 623. http://dx.doi.org/10.1039/c0ay00092b.

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Guo, Hong Min, and Xiang Jie Yang. "Continuous Fabrication of Sound Semi-Solid Slurry for Rheoforming." Solid State Phenomena 116-117 (October 2006): 425–28. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.425.

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An alternative method has been proposed for the continuous and sample production of SSM slurry for the rheo-forming process. The process named “Low Superheat Pouring with a Shear Field (LSPSF)” dose not use the conventional stirring process, instead, it uses solidification conditions to control nucleation, nuclei survival and grain growth by means of low superheat pouring, vigorous mixing and rapid cooling during the initial stage of solidification combined with thereafter a much slower cooling. The method has been applied to A356, 201 and A380 Al-alloys. The primary phases present in average equivalent diameter of 40-70μm, 35-50μm and 50-70μm for A356, 201 and A380, respectively. The morphology of primary phases is nearly spherical with shape factor of 0.78-0.86, 0.71-0.83 and 0.85-0.96 for A356, 201 and A380, respectively. For each of those alloys, there is no eutectic entrapped within the primary phase. The advantages of the LSPSF include process simplicity with high efficiency, easy incorporation into existing metal forming installation without infrastructure changes and a wide process window for pouring temperature.

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Zhao, Hong Jin, Yong Lin Kang, Zhao Hui Wang, and Hai Liang Du. "Effect of Disturbing Conditions in Semi-Solid State on Microstructure Evolution of Magnesium Alloy." Solid State Phenomena 116-117 (October 2006): 296–99. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.296.

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In this paper the microstructure evolution of AZ91HP magnesium alloy casts produced under different disturbing treatment conditions such as non-disturbing, argon blowing and mechanical stirring in semi-solid state after holding a short time was studied. The results show that the grains of AZ91HP alloy casts refined, the secondary dendritic arms grown and the dendrites tend to rosette shape with the decrease of holding temperature. External disturbance can accelerate the evolution process, and the spherical primary α phase formed easily under mechanical stirring treatment condition. The formation of non-dendritic structure is owing to ripening of the dendritic arms, refinement of the grains and movement of the primary formed solid phases. Disturbing treatments in semi-solid state induce more equilibrium solidification and decrease the amount of brittle β-Mg17Al12 phase. Blowing argon into the refined and modified magnesium alloy in semi-solid state can obtain homogeneous non-dendritic structure and the net shaped β phase distributed on α-Mg phase boundaries become fine and thin, this may be have a good effect on the mechanical properties of the magnesium alloy casts. Due to the low disturbing strength, argon blowing can maintain the metallurgy quality of the semi-solid slurry well, and also have high efficiency to make it. This technology need not new complex equipments and can be practiced in conventional casting conditions, so it may be used in industrialize manufacture.

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Seyboldt, Christoph, Mathias Liewald, and Daniel Heydt. "Production of Aluminium Based Interpenetrating Phase Composites Using Semi-Solid Forming." Key Engineering Materials 716 (October 2016): 502–9. http://dx.doi.org/10.4028/www.scientific.net/kem.716.502.

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The following paper deals with the production of Interpenetrating Phase Composites (IPC) using semi-solid forming technology. Therefore, adequate ceramic foams were selected and infiltrated by processing the aluminium alloy A356 in the semi-solid state. In the studies presented in this paper, the infiltrations of two ceramic materials (Al2O3 and SiC) with three different pore sizes (10, 20 and 30 ppi) were investigated. During the forming process the liquid phase fraction of the aluminium was varied to analyze infiltration effects in relation to the raw material´s liquid phase fraction. Afterwards, microsections of the produced specimens were analyzed in order to characterize their microstructure and the quality of infiltration. The results showed that completely filled composite components with good mechanical properties can be produced by infiltrating ceramic preforms with a semi-solid aluminium alloy.

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Jiang, Ruifen, Wei Lin, Lifang Zhang, Fang Zhu, and Gangfeng Ouyang. "Development of a novel solid phase microextraction calibration method for semi-solid tissue sampling." Science of The Total Environment 655 (March 2019): 174–80. http://dx.doi.org/10.1016/j.scitotenv.2018.11.226.

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Kang, Suk Won, Ki Bae Kim, Dock Young Lee, Jung-Hwa Mun, and Eui Pak Yoon. "Morphological Evolution of Primary Solid Phase in Semi-Solid Slurry during the Isothermal Holding." Materials Science Forum 510-511 (March 2006): 394–97. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.394.

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Kang, Suk Won, Dock Young Lee, and Ki Bae Kim. "Effect of Preheating Temperature of Multiplex-Type Slurry Cup on the Morphology of Primary Solid Phase of Semi-Solid Slurry." Solid State Phenomena 116-117 (October 2006): 332–35. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.332.

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Semi-solid slurry for a rheocasting process requires a fine and globular structure of primary solid phase. In the present study, in order to find an optimum preheating temperature of a multiplex-type slurry cup in the slurry maker that we recently developed for the rheocasting process, the semi-solid slurry was held for a various time of up to 60 min. in a multiplex-type slurry cup preheated at a different temperature. A size and morphology of primary solid phase of the semisolid slurry was measured and analyzed with the difference of the recorded cooling curve during the solidification with respect to a preheating temperature of the slurry cup. Also, a microstructural evolution and globularization mechanism occurred during the isothermal holding were discussed. Finally, as considering the effect of a different casting condition on the morphology of primary solid phase the optimum manufacturing condition of the semi-solid slurry for the rheocasting process was proposed.

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Shakiba, M., and Hossein Aashuri. "Modeling of Semi-Solid A356 Alloy under Upsetting Process." Solid State Phenomena 116-117 (October 2006): 622–25. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.622.

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The flow behavior of a semi-solid A356 alloy at high solid fraction was studied. The mushy zone was considered as an effective two-phase, so that the solid continuum can be compressible porous media, and the liquid phase interaction with the solid skeleton was of Darcy type. The semi-solid flow through the upsetting test was modeled in ABAQUS finite element method software. The Gurson yield criterion has been developed for the modeling process of the flow behavior of solid porous medium. Specimens were globulized by a thermomechanical process and then were tested for various percentages of upsetting. The distribution of solid fraction along the radius of the specimens at different height reduction showed a good correlation with model prediction.

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Curle, Ulyate Andries, and Jeremias D. Wilkins. "Semi-Solid Casting of Pure Magnesium." Solid State Phenomena 285 (January 2019): 464–69. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.464.

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Semi-solid processing works on the principal of a solidification temperature interval of a substance. The substance is heated to a temperature within this interval so that there exists a related solid-liquid fraction ratio. The substance with this phase structure is then shaped by a forging or casting process. It has been stated before that it is impossible to semi-solid process and cast pure metals or eutectic alloys due to their thermodynamic temperature invariance, meaning that there is no temperature interval. It was demonstrated recently that it is possible to semi-solid casting high purity aluminium (Curle UA, Möller H, Wilkins JD. Scripta Materialia 64 (2011) 479-482) and the Al-Si binary eutectic (Curle UA, Möller H, Wilkins JD. Materials Letters 65 (2011) 1469-1472). The working principal is that there exists a time interval during thermal arrest during which solidification takes place with a solid-liquid fraction ratio until all the liquid is consumed upon cooling. The aim with this work is to demonstrate that pure magnesium can also be rheo-high pressure die cast (R-HPDC) with the system developed at the CSIR in South Africa. Magnesium is notoriously difficult to cast due to the thermal properties of magnesium. The metal was poured into a cup, processed for about 6 seconds after which it was HPDC into a plate. The microstructure of the casting consists of a structure that was solid and a structure that was liquid during thermal arrest at the time of casting.

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Pineau, Frédéric, and Geneviève Simard. "Investigation of the Primary Phase Segregation during the Filling of an Industrial Mold with Semi-Solid A357 Aluminum." Solid State Phenomena 141-143 (July 2008): 635–40. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.635.

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Casting metal alloys in the semi-solid state is now becoming a well established manufacturing technique. But, the success of this technology necessitates a good understanding of the feedstock material behaviour. To obtain high quality components with semi-solid metal processing, a homogeneous distribution of phases must be maintained in the material during the die filling stage. Many parameters affect the process such as temperature, time and stress history, which influence the shape, size and connectivity of the particles that make up the slurry. The subsequent phase interaction mechanisms are quite complex and have direct effects on the flow and final micro-structure distribution of the cast part and thus, without any doubt, on its mechanical properties. Two-phase numerical models have been developed to account for the liquid-solid phase separation e.g. [1,2]. Several two-phase models have been elaborated on the basis of soil mechanics and consider that the phase interaction term is mainly due to the flow through a porous medium. Because of the difficulties of making direct measurements in an extremely hostile environment, there has been very little work done to validate these models. In order to fill this gap, a better understanding of the phase distribution and phase segregation mechanisms during the filling step is required. In this work, the post-solidification primary α-phase distribution inside an industrial semi-solid cast part has thus been investigated. A thorough metallographic analysis has been performed using an upright microscope coupled to a Clemex image-analysis software. The results were then processed to produce a map of the final α-phase distribution. Many different grain scales have been observed in the solidified part and their distributions seem to be closely associated to the velocity field. Contacts between moving particles seem to play an important role in the phase distribution and show many similarities to granular materials. This latter aspect should be considered in the development of new constitutive models for semi-solid slurries.

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Hu, Yong Jun, Bin Qiang Zhong, Feng Li, Xiao Ling Cheng, Xiao Ting Xiao, Yong Li, Jian Nan He, et al. "Microstucture and Mechanical Properties of Semi-Solid Sn–58Bi Alloy." Key Engineering Materials 480-481 (June 2011): 687–90. http://dx.doi.org/10.4028/www.scientific.net/kem.480-481.687.

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Preparation of semi-solid Sn–58Bi alloys by mechanical stirring casting method was investigated. The effect of temperature below the melting temperature on the microstructures and mechanical properties of semi-solid Sn–58Bi alloys was discussed. The experimental results showed that long plate shape, block shape and suborbicular Sn phases were formed by mechanical agitation during the casting solidification process. The non-lamellar Sn-Bi Microstructure improves prominently the elongation of Sn-Bi alloy. The elongation of semi-solid Sn-Bi alloy with suborbicular Sn phase is enhanced up to 37% compared with the elongation of lamellar eutectic Sn-Bi alloy prepared by conventional die casting. After the agigation above 130 °C, non-lamellar Sn-Bi eutectic structure is formed and lamellar Sn-Bi eutectic precipitates. When the agitating temperature was 135 °C, the elongation of semi-solid Sn-Bi alloy mixed with non-lamellar and lamellar Sn-Bi alloy microstructure is enhanced up to 24%.

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Son, Yong Guk, Sung Soo Jung, Yong Ho Park, and Young Cheol Lee. "Effect of Semi-Solid Processing on the Microstructure and Mechanical Properties of Aluminum Alloy Chips with Eutectic Mg2Si Intermetallics." Metals 11, no. 9 (September 7, 2021): 1414. http://dx.doi.org/10.3390/met11091414.

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This study reports the microstructural changes and mechanical properties of high-strength aluminum alloy chips prepared in the semi-solid state at different temperatures, pressures, and holding times. In semi-solid processes, these processing parameters must be optimized because they affect the microstructure and mechanical properties of the chips. In microstructural analysis, these parameters clearly influenced the spheroidization of the aluminum matrix. The aluminum matrix was uniformly spheroidized after semi-solid processing, and the densities of the final samples increased with the holding time. After 30 min holding time at a given temperature, the density approached the theoretical density, but the compressive strength of the samples seriously deteriorated. Meanwhile, fracture surface investigation revealed a deformed Mg2Si phase, which is formed through a eutectic reaction. The strength of this phase significantly decreased after increasing the holding time of the semi-solid processing from 10 to 30 min. Therefore, deformation of the Mg2Si phase caused by diffusion of aluminum into this phase can be a key factor for the decrease in the mechanical properties of samples fabricated with 30 min holding time.

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Wu, Shu Sen, Xiao Gang Fang, Shu Lin Lü, Li Zhao, and Jing Wang. "Semi-Solid Processing and Properties of RE-Containing Mg Alloys." Solid State Phenomena 256 (September 2016): 75–80. http://dx.doi.org/10.4028/www.scientific.net/ssp.256.75.

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The RE-containing Mg alloys usually have big RE-rich intermetallic compounds distributed along grain boundaries. In this paper, a 3 wt.% RE containing Mg alloy is processed by combination of semi-solid slurry-making with ultrasonic vibration (UV) and squeeze casting. Results show that good semi-solid slurry with fine and spherical primary α-Mg particles can be obtained due to the effects of the cavitation and acoustic streaming induced by UV, and the average particle size and average shape factor are about 30 μm and 0.70 respectively. The RE-rich intermetallic compounds are refined and uniformly distributed along grain boundaries. With the increase of squeeze pressure from 0 MPa to 200 MPa during the casting of semi-solid slurry, the tensile strength and the elongation of the as-cast samples are increased continuously, which reach 182 MPa and 8.4% respectively. The microstructure is also analyzed with SEM, TEM, XRD and EDS, and the phase constitutions of this Mg-RE-Zn-Y-Zr alloy are mainly α-Mg matrix, α-Zr, W phase (Mg3Zn2Y3), I phase (Mg3Zn6Y) and T phase ((La,Ce)(Mg1-xZnx)11). The mechanism of refinement of RE-rich intermetallic compounds is also discussed.

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Zhang, Ying, Jin Hua Xu, Shui Sheng Xie, Mao Peng Geng, Hong Min Guo, and Hai Bo Zhao. "Effect of Annealing on Microstructure and Properties for Semi-Solid Magnesium Strips." Materials Science Forum 704-705 (December 2011): 581–85. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.581.

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The experiment of the roll-casting for semi-solid AZ91D magnesium was carried out on the equipment made by ourselves in our laboratory. Parameters of annealing process and the effect of annealing temperature on structure and hardness of semi-solid magnesium were investigated. It was shown that annealing process can improve the structure and properties of roll-casting strips for semi-solid magnesium. In addition, it can relieve the eutectic structure segregation and make β-Mg17Al12 phase precipitate from primary α-Mg grain, which can cause dispersion strengthening process when the annealing temperature is about 420°C. With the increasing of annealing temperature, semi-solid primary α-Mg grain boundary become obscure gradually, grain growth is indistinct and β-Mg17Al12 phase is precipitated from the inner α-Mg grain. However, the aberrated eutectic α-Mg grain for non-equilibrium solidification increase continuously and separate gradually from β-Mg17Al12 phase, which makes the β-Mg17Al12 phase connect together and distribute on the α-Mg grain boundary closely approaching the equilibrium solidification structure. Hardness in eutectic structure area is higher than primary α-Mg grain. With the increasing of annealing temperature, hardness in eutectic structure area will increase and then decrease, when the temperature is over 400°C, the hardness will increase again, but hardness of primary α-Mg grain nearly unchanged. Keywords: casting-rolling; anneal; semi-solid; magnesium alloy; microstructure

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Wang, Yao, Yuanxing Li, Dengquan Han, Sifu Qiu, and Hui Chen. "Microstructure evolution and mechanical properties of 6N01S-T5 aluminum alloy joints with semi-solid solders by ultrasonic soldering." International Journal of Modern Physics B 33, no. 01n03 (January 30, 2019): 1940027. http://dx.doi.org/10.1142/s0217979219400277.

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The article investigated the properties of 6N01 aluminum alloy joints with Sn-80Zn semi-solid solders by ultrasonic soldering. It was found that semi-solid solders consisted of Zn-rich phase with short rod-like dentrite, which had the lower solidus temperatures, while Zn-rich phase with long dentritic grains used the conventional solders. The joints soldered with Sn-80Zn conventional filler metal reached maximum shear strength of 73 MPa at the soldering temperature of 390[Formula: see text]C. The joint using Sn-80Zn semi-solid solder obtained higher shear strength of 90 MPa at the lower temperature of 370[Formula: see text]C. The effects of the ultrasonic time and the soldering temperature on the mechanical properties of the joints were also investigated with the Sn-80Zn semi-solid solders.

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Kang, Suk Won, Dock Young Lee, and Ki Bae Kim. "Optimization of Manufacturing Conditions of Semi-Solid Slurry in Multiplex-Type Slurry Cup." Solid State Phenomena 116-117 (October 2006): 243–46. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.243.

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Recently, we have developed a slurry maker using a multiplex-type slurry cup for rheoforming process. In the present study, the optimum manufacturing condition of semi-solid slurry having a fine and globular structure of primary solid phase was investigated in the multiplextype slurry cup. A various manufacturing condition, such as a pouring temperature of melt, a preheating temperature of slurry cup, and a holding temperature and time of melt in slurry cup was varied to make a processing map of the semi-solid slurry for rheoforming process. Through the microstructural examination of primary solid phase of the interrupt-quenched semi-solid slurry of Al-7wt%Si-0.35wt%Mg alloy produced in the multiplex-type slurry cup under a various manufacturing condition, the optimum manufacturing condition of the semi-solid slurry for rheoforming process were a pouring temperature of melt of 650, a preheating temperature of slurry cup of 300, and an isothermal holding time of melt in slurry cup of 10min at 580.

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Yi, Rong Xi, Shi Kun Xie, Xiao Qiu Zheng, and Yong Ping Ai. "Effect of RE on Performance of Semi-Solid AlSi7 Alloy." Key Engineering Materials 426-427 (January 2010): 581–84. http://dx.doi.org/10.4028/www.scientific.net/kem.426-427.581.

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The semi-solid slurry of AlSi7 alloy was prepared by near-liquids cast processing. The effects of different content of RE on the cast performance and the semi-solid remelting performance in AlSi7 alloy was researched. The results indicated that adding RE will widen the AlSi7 alloy solid-liquid two-phase zone temperature and refine the grains, silicon will obvious metamorphoses. The best amount of RE is about 0.5%. Its semi-solid remelting organization is equilateral globular grains.

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Guo, Hong Min, Le Rong Bai, Bin Liu, and Xiang Jie Yang. "Ti-Zr-V-Cu-Be BMGMCs Processed by Semi-Solid Processing." Solid State Phenomena 285 (January 2019): 111–14. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.111.

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Compared with monolithic bulk-metallic glasses at room temperature, in-situ two-phase bulk metallic glass matrix composites (BMGMCs) exhibit improved toughness. However, most of in-situ BMGMCs are developed through extremely rapid cooling, during which the solidification process cannot be controlled effectively. As a consequence, the microstructures of in situ two-phase composites, even with the same composition, vary from one to another, highly depend on the cooling rate. In the present investigation, the Ti-Zr-V-Cu-Be BMGMCs was prepared by using copper mould suction process, and the evolution of microstructures at semi-solid stage was investigated. The results indicated that microstructures of billets, produced by copper mould suction and water quenching after isothermal holding at semi-solid stage, mainly contained β-Ti phase and glass matrix. Isothermal holding temperature and time interval determined the final morphology of β-Ti phase. Compression tests showed that semi-solid processing could further improve ductility of BMGMCs effectively.

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Hallstedt, B. "Use of Calphad Thermodynamics to Simulate Phase Formation during Semi-Solid Processing." Solid State Phenomena 141-143 (July 2008): 641–46. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.641.

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In this work we will explore the use of thermochemical simulation methods (Calphad) to support alloy selection and processing in the semi-solid state. Semi-solid processing has been investigated extensively for aluminium alloys, in particular A356, but there is also an increasing interest in using semi-solid processing for steels, in particular high carbon steels. A key property for the semi-solid processing is the fraction of liquid phase as function of temperature. It is necessary to know the fraction of liquid phase in order to be able to control the process and in order to simulate the viscous flow during various forming operations. The approach used here is to calculate the fraction of liquid phase from thermodynamic (and diffusion) data, using equilibrium calculations, Scheil–Gulliver calculations and diffusion simulation. Normally only the solidification behaviour is considered, but during thixoforming also the melting behaviour is of importance. However, there is very little information on melting of alloys to be found in the literature. Here an attempt will be made to discuss also melting as it cannot in all cases be regarded as the reverse of solidification. In addition some further properties, such as enthalpy, heat capacity and density as function of temperature will be discussed. The materials treated are the aluminium alloy A356 and the tool steel X210CrW12. Interestingly they show fairly similar solidification behaviour.

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Kuwahara, Takashi, Taro Osaka, Mizuki Saito, and Shinsuke Suzuki. "Compressive Properties of A2024 Alloy Foam Fabricated through a Melt Route and a Semi-Solid Route." Metals 9, no. 2 (January 29, 2019): 153. http://dx.doi.org/10.3390/met9020153.

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A2024 alloy foams were fabricated by two methods. In the first method, the melt was thickened by Mg, which acts as an alloying element (melt route). In the second method, the melt was thickened by using primary crystals at a semi-solid temperature with a solid fraction of 20% (semi-solid route). A2024 alloy foams fabricated through the semi-solid route had coarse and uneven pores. This led to slightly brittle fracture of the foams, which resulted in larger energy absorption efficiency than that of the foams fabricated through the melt route. Moreover, A2024 alloy foams fabricated through the semi-solid route had a coarser grain size because of the coarse primary crystals. However, by preventing the decrease in the alloying element Mg, the θ/θ’ phase was suppressed. Additionally, by preventing the precipitation of the S′ phase, the amount of Guinier-Preston-Bagaryatsky (GPB) zone increased. This resulted in a larger plateau stress.

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Khunbanterng, Nisachon, Sirikul Wisutmethangoon, Thawatchai Plookphol, and Jessada Wannasin. "Effect of Sr Addition on Microstructure and Mechanical Properties of Semi-Solid 2024 Al Alloys." Applied Mechanics and Materials 496-500 (January 2014): 336–39. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.336.

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Semi-solid 2024 Al alloys with strontium (Sr) addition of 0.15 wt% and 0.3 wt% were prepared by Gas Induced Semi-Solid (GISS) process. Effect of Sr addition on the microstructure and mechanical properties of the semi-solid 2024 alloy was investigated. It was found that the tensile strength and % elongation of the T6 heat treated alloy with the Sr addition were higher than those without Sr addition owing to the reduction of Mg2Si phase formation. The semi-solid 2024 Al alloy with 0.15%Sr addition obtained the average highest tensile strength of 382 MPa and elongation of 6.45%.

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Suéry, Michel, Luc Salvo, Charles Josserond, and Marco Di Michiel. "In-Situ 3D Investigation by Fast X-Ray Microtomography of the Microstructural Changes Occurring during Partial Remelting of Al-Cu Alloys." Solid State Phenomena 116-117 (October 2006): 231–34. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.231.

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The evolution of the microstructure of semi-solid Al-Cu alloys has been characterized during isothermal treatments in the semi-solid state by using in-situ X-ray microtomography experiments carried out at ESRF, Grenoble. This work is therefore a continuation of previous experiments reported at the 8th S2P Conference in Limassol. Quantitative data are presented dealing with changes with holding time of the solid volume fraction, of the solid-liquid interface area and of the mean and Gaussian curvatures of the solid phase. Discussion of the results is carried out on the basis of the mechanisms involved in semi-solid systems.

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Jabbari, Amin, Seyedali Ali Sadough, and Vahid Pouyafar. "Rotational Rheology of A356 Semi-Solid Alloy at Low Solid Fractions." Advanced Materials Research 1019 (October 2014): 74–80. http://dx.doi.org/10.4028/www.scientific.net/amr.1019.74.

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The main goal of investigations on semi-solid metal processing is to produce complex parts with enhanced mechanical properties. Flow behavior and die filling in semi-solid processing is an intrest area of researchers. A comprehensive understanding of the behavior of the under investigation metallic slurry is the design key of a successful manufacturing process. In this way the material’s transient response is very important for understanding of the rheological properties and also further commercial development of the process. The material used in this research is an Al-Si alloy which is widely used in automotive and aerospace applications. The experiments were conducted using a Searl rheometer which is specially designed for high temperature rheological measurements. For rheological tests of semi-solid alloy in different solid fractions, the isothermal holding and shear rate step change experiments were examined. Using practical rheological results, a single phase thixotropic model has been derived and adopted with measurements. The investigated alloy behavior was obviously thixotropic which is quantified in a theoretic model. Also instantaneous rheopectic behavior was observed for this alloy. The state of the microstructure has been applied through a structural parameter. The presented model for A356 alloy fits well with the experiments.

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Qu, Wen Ying, Da Quan Li, Zhi Peng Guo, Min Luo, Fan Zhang, Stephen P. Midson, Xiao Gang Hu, and Yong Zhong Zhang. "Using the Phase Field Method to Investigate Microstructural Evolution of Semi-Solid 357.0 Slurries." Solid State Phenomena 285 (January 2019): 367–72. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.367.

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Semi-solid aluminum slurries have globular grains, different from traditional dendritic solidification microstructures. The mechanism responsible for the formation of these globular grains is still in dispute. Some researchers suggest that the globular grains are formed by fractured dendrites, while others report it is due to copious nucleation. This study will model the growth of the α-Al phase during the production of semi-solid slurries using the swirled equilibrium enthalpy device (SEED) process, where liquid alloy with a low superheat is poured into a steel crucible and swirled within the semi-solid region. Experimental observations have shown that the final microstructure of the slurry produced by the SEED process is relatively non-uniform, with large dendrites at surface and fine spherical particles at the center. Open source code for the phase field method has been adopted to simulate the different microstructural evolution for semi-solid alloy 357.0. The effect of localized temperatures under isothermal condition on the morphology of the α-Al particles has been investigated according to the special conditions of the SEED process. In addition, suggestions for modifying the slurry production to achieve more uniform microstructure are discussed.

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Li, Jiqiang, Lei Zhang, Xuan Pu Dong, Wen Liu, and Zhao Zhang. "Study on Microstructure of Semi-Solid Magnesium Alloy Manufactured by Gas Bubbles Stirring." Advanced Materials Research 129-131 (August 2010): 728–32. http://dx.doi.org/10.4028/www.scientific.net/amr.129-131.728.

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The semi-solid slurry of AZ31 magnesium alloy was manufactured by gas bubbles stirring. The effects of stirring temperature and stirring time on the microstructure of semi-solid slurry were researched. The results indicate that it is feasible to manufacture the slurry with particle-like primary phases. When the stirring temperature is higher, the morphology of the primary a-Mg presents rosette-like morphology and the size of grain is coarse, and the morphology mainly was α- Mg dendrite at lower stirring temperature. Long stirring time could reduce dendrites and liquid phase, and made the non-dendritic grains well spheroidized. But the effects of longer stirring on shape and size of primary particles are not significant. The optimal process parameters for ideal semi-solid slurry manufactured were stired 3min at 645°C.

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Kim, Jeong Min, Bong Koo Park, Joong Hwan Jun, Ki Tae Kim, and Woon Jae Jung. "Microstructure and Mechanical Properties of Cast and Semi-Solid Formed Mg-Al-Zn Alloys." Solid State Phenomena 116-117 (October 2006): 288–91. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.288.

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Various Mg-Al-Zn alloys with different Al and Zn contents were fabricated by conventional casting and semi-solid forming process. And the microstructure and mechanical properties of the alloys were investigated. In Mg-4%Al-(5~7)%Zn alloys most of the grain boundary phases were found to be Mg-Al-Zn while in Mg-6%Al or Mg-8%Al based alloys the Mg- Al-Zn phase coexisted with Mg17Al12 at grain boundaries. At room temperature the semi-solid formed alloys showed significantly higher tensile properties, especially elongation, than the conventionally cast alloys.

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Lyapunov, N. A., E. P. Bezuglaya, A. N. Lyapunov, I. A. Zinchenko, K. Yu Bryleva, and A. A. Lysokobilka. "LABORATORY EQUIPMENT DURING PHARMACEUTICAL DEVELOPMENT OF SEMI-SOLID PREPARATIONS." Drug development & registration 8, no. 1 (February 14, 2019): 29–36. http://dx.doi.org/10.33380/2305-2066-2019-8-1-29-36.

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Introduction. When developing drugs it is necessary to use laboratory equipment that simulates pilot and industrial equipment. For the production of semi-solid preparations the key equipment are rotor-stator dispersers and vacuum reactors-homogenizers. Aim. Investigation of the functional characteristics of laboratory equipment: Megatron® MT 1-50 dispersant SHS F/2 (Kinematica AG, Switzerland) and the RP-5 vacuum homogenizer reactor (Promvit, Ukraine). Materials and methods. During development a generic product Penciclovir cream 1% the initial particle size in suspension of penciclovir and particle size after grinding were studied by optical microscopy and laser diffraction methods. In a cream made in the reactor, the particle size of the dispersed phase of the o/w emulsion and suspension, as well as the absence of air bubbles, were determined by optical microscopy. The assay of penciclovir in 9 samples of the cream taken from the reactor-homogenizer was performed by liquid chromatography. By the of rotational viscometry method the rheological properties of the cream were studied. By the inductively coupled plasma atomic emission spectroscopy the getting of metal impurities from the disperser and the reactor-homogenizer into the suspension and cream were investigated. Results and discussion. With an increase in the rotor speed, the particle size of penciclovir in suspension decreases. The disperser effectively performs its function at a rotor speed of 25,000 rpm. In a cream made in the reactor, the deviations in the quantitative content of penciclovir from the average value in each sample are within the uncertainty of the analytical procedure, which indicates its uniform distribution. The reactor provides effective dispersion and uniform distribution of the oil phase, prevents the formation of a gas emulsion and allows getting a cream that, according to its rheological properties, corresponds to the reference preparation Fenistil® Pencivir cream 1%. In the production process metal impurities were not emitted into the suspension and the cream from the equipment. Conclusion. The disperser and the reactor during the production of cream with penciclovir are suitable for their intended use. It is rational to combine these two types of equipment at the sites for the production of semi-solid preparations. The disperser can also be used to produce emulsions with a very small particle size of the dispersed phase.

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Behúlová, Mária, David Aišman, Hana Jirková, and Bohuslav Mašek. "Experimental and Numerical Investigation of the Steel X210Cr12 Forming in Semi-Solid State." Advanced Materials Research 214 (February 2011): 461–66. http://dx.doi.org/10.4028/www.scientific.net/amr.214.461.

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Semi-solid forming processes belong to the progressive technologies which can be exploited for the manufacturing products with complicated shapes and special material and utility properties. Semi-solid metal forming takes place at temperatures between solidus and liquidus combining the advantages of metal forging and metal casting processes. The paper is focused on the analysis of microstructures and phase composition of the X210Cr12 steel identified in the thin-walled products after forming in semi-solid state. Microstructure of the X210Cr12 steel after rapid cooling and solidification from semi-solid state is formed by quasi-globular grains of metastable austenite surrounded by carbides and fine eutectics. The fraction of metastable austenite in structure was found to be 96 % exhibiting the thermal stability up to the temperature of 500 °C. Along with experimental study, the numerical analysis of the material flow during a die cavity filling was carried out using developed 2D simulation model taking into account one-phase non-newtonian flow.

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Zhao, Yong Qing, Xue Dan Ma, Wei Lu Wu, Liang Feng, Hai Ying Yang, and Lanlan Yu. "Research on Semi-Solid Oxidation Behavior of Ti14 Alloy." Materials Science Forum 475-479 (January 2005): 569–72. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.569.

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The semi-solid oxidation behavior of Ti14 alloy was researched. The results show that the weigh gain increases obviously with the increasing of the semi-solid oxidation temperature. After semi-solid oxidation, the oxidation scales are only TiO2 and there are not any oxides of Cu. That is the result of the evaporation of CuO. The evaporation of CuO, which is over 1050°C, makes the weight grain happen to decrease. The oxidation layer consists of five regions. Because of the existence of the low-melting-point-phase (Ti2Cu), the melting grain boundaries become the preference walkway for the oxygen diffusion.

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Govender, Gonasagren, Heinrich Möller, and Ulyate Andries Curle. "Alloy Design for Semi Solid Metal Forming." Materials Science Forum 783-786 (May 2014): 136–41. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.136.

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Semi-solid metal forming is more than 40 years old but its full potential to near net shape form high strength aluminium alloys has been realised only to a limited degree. Alloys developed for traditional manufacturing processes were initially used but it became apparent that alloys specific to SSM forming needed to be developed. The main alloy development criteria revolved around SSM processing temperature, solid fraction (fs) versus temperature sensitivity and age hardening potential. This methodology while sound does not fully address the unique processing behaviour of SSM forming. By its very nature SSM requires the controlled solidification of a part of the melt before forming. From basic solidification fundamentals this results in the enrichment of the remaining liquid with alloying elements. During the forming process segregation of liquid phase essentially produces a component with very different compositions in the regions where the liquid solidifies last. From recent work completed on a wide range of standard alloy systems it has become apparent that this segregation effect has a significant impact on aging behaviour and strength. Low melting point structures formed in the these regions result in localised melting in the grain boundary region and along areas of gross liquid segregation during solution heat treatment, contributing to the poor mechanical properties. Although this behaviour can be addressed using modified heat treatment, this cannot be applied to all current alloy systems. Alloy design for SSM forming must take these phenomena into account in order to develop and or specify aluminium alloys with acceptable mechanical properties.

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Knauf, Frederik, I. Seidl, and Gerhard Hirt. "Rheoforging of Steel." Solid State Phenomena 116-117 (October 2006): 464–67. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.464.

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Rheoforging is a modification of semi-solid forging starting directly from the liquid phase instead of reheating of a billet. In this process semi-solid slurry is prepared by pouring slightly overheated melt over a slope into a holding cup to induce homogenous nucleation. By controlling the casting temperature and holding time in the cup the desired semi-solid slurry with fine, globular microstructure is successfully created. The inline forging trials using this slurry show the principal feasibility of the process.

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Kim, Jeong Min, Gun Ha Lee, Joong Hwan Jun, Ki Tae Kim, and Woon Jae Jung. "Development of Heat Resistant Mg-Al-Ca Based Alloys for Casting and Semi-Solid Forming." Solid State Phenomena 116-117 (October 2006): 68–71. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.68.

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Mg-8%Al-1%Ca was selected as a base alloy composition and small amounts of minor alloying elements, RE or Sr, were added. Microstructure of as-cast Mg-8%Al-1%Ca base alloys consists of dendritic primary Mg, Mg-Al-Ca and Mg17Al12 phases. Mg-Al-RE-(Ca) phase in the RE-added alloys and Mg-Al-Sr-(Ca) phase in the Sr-added alloys were additionally found. The creep resistance of Mg-8%Al based alloy was significantly improved by the minor alloying elements additions with 1%Ca. Comparatively globular primary phase could be obtained after just 30min. through an isothermal heating of as-cast Mg-Al-Ca alloys.

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Schomer, Laura, Christoph Seyboldt, and Mathias Liewald. "Semi-Solid Metal Forming - A Process for Manufacturing Composite and Hybrid Materials." Defect and Diffusion Forum 381 (November 2017): 47–51. http://dx.doi.org/10.4028/www.scientific.net/ddf.381.47.

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The following paper deals with the manufacturing of composite and hybrid materials by using semi-solid forming technologies. On the one hand, there is presented a process for producing Interpenetrating Phase Composites (IPC) consisting of ceramic open-cell structures which are infiltrated by a semi-solid aluminium alloy. On the other hand, a new process for manufacturing hybrid metallic materials is described. Thereby, semi-finished materials made of two different aluminium alloys are simultaneously heated using an induction system and subsequently formed in the semi-solid state. The paper shows numerical investigations as well as experimental results for both processes.

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Liu, Zheng, Xiao Mei Liu, and Wei Min Mao. "Semi-Solid A356 Alloy Slurry Prepared by Slightly Electromagnetic Stirring with Ti-Based Refiner." Advanced Materials Research 152-153 (October 2010): 1745–50. http://dx.doi.org/10.4028/www.scientific.net/amr.152-153.1745.

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The semi-solid A356 alloy slurry is prepared by slightly electromagnetic stirring with Ti-based refiner. The effects of the refiner on the morphology and the grain size of the primary phase in the slurry are researched. The results indicate that the slurry with particle-like and rosette-like primary phases can be prepared by slightly electromagnetic stirring with the refiner. Compared with the A356 alloys without the refiner, the grain size and particle morphology of primary phase as well as the distribution of the grain with particle-like or rosette-like along radial in the ingot in A356 are markedly improved by the refiner.

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47

Li, Long Fei, Da Quan Li, Min Luo, Yong Zhong Zhang, Yong Lin Kang, Qiang Zhu, and Stephen P. Midson. "Influence of Rare Earth Additions on the Microstructure and Mechanical Properties of Al7Si0.3Mg Alloys Processed by Semi-Solid Die Casting and Gravity Die Casting." Solid State Phenomena 285 (January 2019): 69–74. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.69.

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Microstructures with fine globular grains and refined eutectic structures are important to enhance the mechanical properties of A356 alloys processed by semi-solid and gravity die casting. Rare earth (RE) additions have been shown to be capable of refining both the α-Al particles as well as modify the eutectic phase of alloys. In semi-solid die casting, Al7Si0.3Mg alloys with RE concentrations (0, 0.1 and 0.4 wt.%) were used to prepare semi-solid slurries using the SEED (Swirling Enthalpy Equilibrium Device) method, and subsequently semi-solid die cast. The same compositions of alloys were also applied to gravity die casting. The microstructure and mechanical properties of castings in two processes have been characterized. Compared to the grains produced in gravity die casting, globular grains with small size (260 μm) in the semi-solid die casting significantly enhance the UTS and elongation of alloys. Although the size of grains had no change with increasing RE concentrations in alloys. The Al-Si eutectics were changed to refined morphology with the 0.1 wt.% RE addition, which enhanced the ductility of alloys in two processes. When increasing the RE addition to 0.4 wt.%, the RE-rich phases precipitated at grain boundaries, which decreased the UTS and elongation of alloys.

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Traidi, Khalil, Véronique Favier, Philippe Lestriez, Karl Debray, Laurent Langlois, and Tudor Balan. "Modelling Semi-Solid Behaviour and Brittle Temperature Range." Solid State Phenomena 285 (January 2019): 361–66. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.361.

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In this paper, a new elastic viscoplastic micromechanical modelling is proposed to represent the semi-solid behaviour and predict the ductile-brittle transition of the C38LTT near the solidus. It is based on a viscoplastic modelling previously presented in [1]. The originality of the new model comes from three main enhancements: the transition between the solid state and the semi-solid state was included meaning that the material properties were taken temperature-dependent, the elastic properties was taken into account similarly as [2] and the evolution of the internal variable describing the degree of agglomeration of the solid phase was enhanced. The model was implemented in the commercial software FORGE©. Tensile tests representing the experimental thermal conditions and obtained using a GLEEBLE© machine were simulated. The comparison of the predicted and experimental results shows that, for the first time to our knowledge, the three steps of the load-displacement response and ductile-brittle transition were successfully described.

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Han, Hong Jing, Yan Guang Chen, Hong Qi Wang, Wen Guo Duan, Chao Guo, Wen Xue Yuan, and Yan Qun Guo. "Investigation of Iodine Distribution in the Semi-Hydrate Wet Phosphoric Acid Process." Advanced Materials Research 807-809 (September 2013): 1347–50. http://dx.doi.org/10.4028/www.scientific.net/amr.807-809.1347.

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The influencing factors of reaction such as reaction temperature, reaction time and the ratio of liquid to solid are investigated by analyzing the iodine distribution in the semi-hydrate wet process of phosphoric acid. The result shows that with the increase of reaction temperature, reaction time and the ratio of liquid to solid, the iodine distribution in the phases of liquid and solid presents has the tendency of decrease, in the range between 20% and 30%, while the iodine distribution in the gas phase tends to increase, the maximum value is 67.54%.

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Wang, Jia Xuan, Chun Li, Li Hong Jiang, and Min Fang. "Influence of Ultrasonic Vibration on Preparation for Semi-Solid A356 Alloy." Advanced Materials Research 295-297 (July 2011): 1465–69. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.1465.

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In this paper, semi-solid slurry was prepared by power ultrasonic on flowing A356 melts. A simple device of ultrasonic treatment was made and the method of applying power ultrasound from the top of ingot was adopted. we investigated the influence of the experimental parameters impact on the size and morphology of the primary phase α-Al in A356 slurry, which included the power of the power ultrasound, treatment temperature and the distance between ultrasonic source and the melts ( here refer to from vibration head to the bottom of melt channel in this paper). The regularity of ultrasonic influence on grain refinement and morphology spheroidizing of primary phase α-Al in A356 alloy were obtained. The results show that when the loading power range from 800W to 1000W, the grain refinement effect goes more obviously with the increasing power of ultrasonic, howerer, when the power is up to 1500W, the effect goes worse; and the best primary phase is obtained at 615 oC among the four treatment temperature (645 °C, 630 °C, 615 °C, 600 °C); with the increase of the distance, among the four groups data (7mm, 9mm, 12mm, 15mm), the microstructure of A356 alloy goes more coarse and the segregation is more serious, the average grain size and form factor of the best primary phase α-Al was 29.47um and 0.78, respectively in this study.

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Journal articles on the topic 'Semi-solid phase'

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