Journal articles: 'Cementite'

1

Bhadeshia, H. K. D. H. "Cementite." International Materials Reviews 65, no. 1 (January 11, 2019): 1–27. http://dx.doi.org/10.1080/09506608.2018.1560984.

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Yang, Yo Sep, S. Y. Park, Hyun Jo Jun, Chan Gyung Park, S. H. Lim, and D. Y. Ban. "Effects of Microstructure on the Fatigue Resistance of Steel Tire Cords." Materials Science Forum 475-479 (January 2005): 4125–28. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.4125.

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Effects of microstructural parameters on fatigue resistance (σFL) of the steel tire cords have been investigated experimentally from microscopic points of view. At first, microstructural parameters depending on carbon content have been identified by using transmission electron microscopy (TEM). The fatigue resistance of the steel tire cords depending on carbon content has been measured by using the Hunter rotating beam tester under the bending stress of 900 to 1500 MPa. The fatigue resistance was improved with increasing the carbon content from 0.7, 0.8 to 0.9 wt. % C, due to variations of microstructural parameters, such as lamellar spacing (λp), cementite thickness (tc), and volume fraction (Vc) of cementite. As the carbon content increased, the lamellar spacing and the cementite thickness decreased, while the volume fraction of cementites increased. The effects of microstructure on fatigue resistance have been discussed in terms of the microstructural parameters mentioned above.

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Kang, Seong Hoon, Hyung Cheol Lim, and Ho Won Lee. "Microstructures and Crack Formation in Hot Compression Test of Ultrahigh Carbon Steel." Key Engineering Materials 611-612 (May 2014): 162–66. http://dx.doi.org/10.4028/www.scientific.net/kem.611-612.162.

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Experimental works were carried out to investigate microstructure and crack formation during compression tests of 1.9wt%Cultrahigh carbon steel according to temperature and strain rate. As-received ultrahigh carbon steel is composed of precipitated cementites and pearlite matrix. In addition, numerous voids were observed in the matrix of as-received material. The compression tests at 800oC showed that the voids within the matrix are closed with increase of reduction ratio. On the other hand, when the reduction ratio increased numerous micro-cracks were newly formed in the bulky cementites and at the interfaces between hard cementite and soft matrix. It was also observed that because the volume fraction of cementite is reduced when temperature increased, volume fraction of newly formed micro-crack significantly decreased. Cast microstructures were observed after compression test at 1130oC due to local melting. From experimental results and microstructure anlayses, it was concluded that the forging temperature should be controlled at the temperature of more than 900oC and less than 1130oC.

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Fan, Xiao Hong, Bin Xu, and Cai Gao. "The Influence of Solvent Metal Microstructure on Synthetic Quality of Diamond Single Crystals." Advanced Materials Research 306-307 (August 2011): 1753–56. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.1753.

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Diamond single crystals are synthesized using artiﬁcial graphite as carbon source and iron-based alloy as catalyst in a cubic anvil apparatus at high temperature and high pressure (HPHT). Four kinds of catalysts at different synthetic times are adopted in synthetic process. After synthesizing the microstructure of the solvent metal samples are characterized by means of scanning electron microscopy (SEM). The results show that when the synthetic quality is relatively superior, the more primary lathy cementites are well distributed and shows parallel growth of the stripe beams. Besides, the edge of the cementite is more even. So the synthesis time and catalyst composition commonly influence the solvent metal microstructure, especially the quantity and shape of cementite.

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Kurita, Masanori, and Akira Saito. "Dependence of Stress Constant on Microstructure of Quenched and Tempered Steels in X-Ray Stress Measurement." Advances in X-ray Analysis 35, A (1991): 519–25. http://dx.doi.org/10.1154/s0376030800009204.

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AbstractThe residual stress measurement of quenched and tempered steels is of practical importance because the quenching can sometimes induce the high residual stress which affects the strength of materials. The stress constants of carbon steels quenched and tempered at various temperatures were measured in order to determine the residual stress of steels by x-ray diffraction. The stress constant increased slowly with increasing tempering temperatures below 500°C; it increased rapidly with tempering temperatures above about 500°C, This rapid increase in the stress constant is closely related to the change in microstructure of the steels in tempering; above the tempering temperature of around 500°C, the tempered martensite recrystallized and transformed to ferritic iron and fine cementite particles dispersed in the matrix; these coalesced and grew to be speroidized cementites and finally laminar cementite plates.

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Todaka, Yoshikazu, Minoru Umemoto, and Koichi Tsuchiya. "Microstructural Change of Cementite in Carbon Steels by Deformation." Materials Science Forum 449-452 (March 2004): 525–28. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.525.

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Deformation and dissolution behavior of the cementite in eutectoid steels with pearlitic and spheroidite structures were studied using high resolution SEM and AFM. Cementite lamellae in deformed pearlite exhibited inhomogeneous slip, smooth thinning or necking, fragmentation and cleavage fracture. Complete dissolution of cementite lamellae and spheroidal cementite particles was observed in specimens deformed with large strains at high strain rates. The dissolution mechanism of cementite by heavy deformation was discussed.

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Zhang, Guo Hong, Dong Woo Suh, and Kai Ming Wu. "Effects of Mn, Si and Cr Addition on the Spheroidization of Cementite in Hypereutectoid Fe-1mass%C Steel." Materials Science Forum 783-786 (May 2014): 1053–57. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.1053.

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Effect of Mn, Si and Cr on spheroidization of cementite in Fe-1mass%C steel has been investigated over a range of austenitizing temperatures. In Fe-1C steel, a fully spheroidized structure is obtained but some large cementite particles are formed. The addition of 1.5 mass% Si or Cr accelerates spheroidization of cementite. An addition of Cr remarkably refine the cementite particle size, but the influence of Si addition on the cementite particle size is not remarkable. A fully spheroidized structure fails to develop in steel with the addition of 1.5% Mn under the condition used in present study. Some lamellar cementite still exist in the 1.5Mn steel. The pearlite-promoting effect of Mn is possibly attributed to the inhomogeneous distribution of cementite particles during the intercritical austenitization.

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Drapkin, B. M., G. M. Kimstach, and T. D. Molodtsoval. "Hardness of cementite." Metal Science and Heat Treatment 38, no. 9 (September 1996): 408–9. http://dx.doi.org/10.1007/bf01395649.

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9

Goodwin, T. J., S. H. Yoo, P. Matteazzi, and J. R. Groza. "Cementite-iron nanocomposite." Nanostructured Materials 8, no. 5 (August 1997): 559–66. http://dx.doi.org/10.1016/s0965-9773(97)00194-3.

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10

Huang, Jun Xia, and Jing Tao Wang. "Equal Channel Angular Pressing in a Pearlitic Structured Steel." Materials Science Forum 539-543 (March 2007): 4692–97. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.4692.

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Equal Channel Angular Pressing (ECAP) in a fully pearlitic structured steel 65Mn was successfully carried out at 923 K via route C in this study. The severe shear deformation of ECAP was accommodated by periodical bending, periodical shearing and shearing fracture etc in the pearlitic lamellae. The cementite in the pearlite has higher plastic deformation capability. Excessive imperfections may be introduced into the cementite, which supplies additional energy driving for the following spheroidization of cementite in subsequent processing. After five ECAP passes, the fully pearlitic lamellae evolved into a microstructure of ultrafine-grained ferrite matrix uniformly dispersed with finer cementite particles. The ferrite matrix is homogeneous with an average grain size of ~0.3 micrometers. Two possible mechanism for the spheroidization of cementite were proposed：heterogeneous growth of the fractured cementite fragments, and the precipitation of new fine spherical cementite particles through nucleation and growth.

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11

Yang, Hong Bo, Fu Xian Zhu, Xiang Hua Liu, and Kuai She Wang. "Effect of Divorced Eutectoid Transformation Temperature on Behaviour of Cementite Growth in GCr15 Steel." Advanced Materials Research 194-196 (February 2011): 296–300. http://dx.doi.org/10.4028/www.scientific.net/amr.194-196.296.

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Cementite spheroidization of GCr15 bearing steel includes granulating and growth of cementite. The effects of divorced eutectoid transformation (DET) temperatures on growth of cementite were studied. It was found that the particles of cementite are fine and uniform when DET occurs at 690～720°С, and alloy elements mostly precipitate at different temperatures during cementite growth of GCr15 bearing steel; Cr and Si mostly precipitate in the eutectoid temperature upper limit, while Mn is in the eutectoid temperature lower limit.

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12

Nagao, A., K. Hayashi, K. Oi, S. Mitao, and N. Shikanai. "Refinement of Cementite in High Strength Steel Plates by Rapid Heating and Tempering." Materials Science Forum 539-543 (March 2007): 4720–25. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.4720.

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The precipitation behavior of cementite in low carbon steels at various heating rates from 0.3 to 100 K/s has been studied using a high-frequency induction heating apparatus. The materials used in this study were steel platesfor welded structures: 610 and 780 MPa class steel plates with a mixed microstructure of bainite and martensite.Cementite was observed using a carbon extraction replica method and the hardness and toughness were also examined. When heated at the conventional slow rate of 0.3 K/s, relatively large cementite particles with an average diameter of 72 nm precipitated at the lath boundaries, whereas when heated at a rapid rate over 3.0 K/s, cementite precipitated both within the laths and at the lath boundaries, and the cementite was refined down to an average diameter of 54 nm. With such refinement of the cementite, the toughness was improved. On the other hand, the hardness was irrespective of the heating rate and was dependent on the tempering parameter. TEM observations of the cementite precipitation behavior during the rapid heating process revealed that cementite begins to precipitate at the lath boundaries at about 773 K and within the laths at about 873 K. It is concluded that rapid heating especially from 773 to 873 K contributes to the cementite refinement and consequently the improvement in toughness. The effect of alloying elements such as chromium, molybdenum or silicon on the cementite growth during the rapid heating and tempering treatment is also discussed.

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13

Gromov, V. E., A. A. Yur’ev, Yu F. Ivanov, V. A. Grishunin, and S. V. Konovalov. "REDISTRIBUTION OF CARBON ATOMS IN DIFFERENTIALLY CHARGED RAILS FOR LONG-TERM OPERATION." Izvestiya Visshikh Uchebnykh Zavedenii. Chernaya Metallurgiya = Izvestiya. Ferrous Metallurgy 61, no. 6 (July 28, 2018): 454–59. http://dx.doi.org/10.17073/0368-0797-2018-6-454-459.

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Using transmission electron microscopy methods at various distances from the rolling surface along the central axis, changes in structure, phase composition, and defective substructure of the head of differentially hardened rails were studied after passed tonnage of 691.8 million tons of gross weight. It is confirmed that prolonged operation of rails is accompanied by two simultaneous processes of transformation of structure and phase composition of plate-pearlite colonies: cutting of cementite plates and dissolution of cementite plates. The first process is carried out by mechanism of cutting carbide particles and removing their fragments, accompanied only by change in their linear dimensions and morphology. The second process of dest ruction of the cementite plates of perlite colonies is carried out by leaving carbon atoms from crystalline lattice of cementite on dislocation, as a result of which phase transformation of rails metal is possible. This is due to a noticeable relaxation of mean energy of carbon atom s binding to dislocations (0.6 eV) and to iron atoms in cementite lattice (0.4 eV). The stages of transformation of cementite plates are considered: enveloping the plates with sliding dislocations and then splitting them into weakly oriented fragments; penetration of sliding dislocations from ferrite lattice into lattice of cementite; dissolution of cementite and formation of nanoscale particles. The presence of nanosized cementite particles in ferrite matrix is noted due to their removal during dislocation slide. Using expressions of modern physical materials science and X-ray diffraction analysis, influence of content of carbon atoms on structural elements of rail steel was estimated. It is shown that prolonged operation of rails is accompanied by a significant redistribution of carbon atoms in surface layer. In the initial state, the main quantity of carbon atoms is concentrated in cementite particles, and after a long operation of rails, along with cementite particles, carbon is located in defects of crystal structure of steel (dislocation, grain boundaries and subgrains), and in the surface layer of steel atoms carbon is also found in crystal lattice based on α-iron.

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14

Zheng, Baochao, Zhifu Huang, Jiandong Xing, Yiyang Xiao, and Fan Xiao. "Effect of chromium content on cementite – pearlite interaction of white cast iron during three-body abrasive wear." Industrial Lubrication and Tribology 69, no. 6 (November 13, 2017): 863–71. http://dx.doi.org/10.1108/ilt-08-2016-0195.

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Purpose This paper aims to demonstrate the effect of varying chromium content on the wear behavior of white cast iron, to study the interaction relationship between cementite and pearlite in white cast iron, while estimating their contribution rate in abrasive wear. Design/methodology/approach To study interaction of cementite-pearlite of white cast irons with different chromium content in three-body abrasive wear, three kinds of chromium white cast iron, bulk single-phase cementite, pure pearlite samples and the white cast iron (WCI), were prepared using the melting and casting technique. The so-called pure pearlite samples have the same chemical composition, microstructure and properties as the pearlite matrix in white cast iron. Findings Results indicated that the interaction has a negative value. Its absolute value decreased with increasing chromium addition. Meanwhile, a high load resulted in an increased interaction value. The contribution rate of cementite to interaction, which was higher than that of pearlite, increased with increasing chromium addition. This indicated cementite was a main phase. Besides, the reductive size of abrasive has a significant effect on the contribution rate at the high load. These prominent cementite occurred fracture, when small size abrasive indented the matrix. These result in the absence of a protective effect of cementite during wear process. Eventually, the contribution rate of cementite decreased significantly. Originality/value This paper demonstrates the effect of varying chromium content on wear behavior of white cast iron, to study the interaction relationship between cementite and pearlite in white cast iron while estimating their contribution rate in abrasive wear.

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Zhang, Jianqiang, and O. Ostrovski. "Cementite Formation in CH4-H2-Ar Gas Mixture and Cementite Stability." ISIJ International 41, no. 4 (2001): 333–39. http://dx.doi.org/10.2355/isijinternational.41.333.

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16

Howe, J. M., and G. Spanos. "Atomic structure of the austenite-cementite interface of proeutectoid cementite plates." Philosophical Magazine A 79, no. 1 (January 1999): 9–30. http://dx.doi.org/10.1080/01418619908214271.

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17

Ivanisenko, Julia, Ian MacLaren, Xavier Sauvage, Ruslan Valiev, and Hans Jorg Fecht. "Phase Transformations in Pearlitic Steels Induced by Severe Plastic Deformation." Solid State Phenomena 114 (July 2006): 133–44. http://dx.doi.org/10.4028/www.scientific.net/ssp.114.133.

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The paper presents an overview of a number of unusual phase transformations which take place in pearlitic steels in conditions of the severe deformation, i.e. combination of high pressure and strong shear strain. Strain-induced cementite dissolution is a well-documented phenomenon, which occurs during cold plastic deformation of pearlitic steels. Recently new results which can shed additional light on the mechanisms of this process were obtained thanks to 3DAP and HRTEM investigations of pearlitic steel deformed by high pressure torsion (HPT). It was shown that the process of cementite decomposition starts by carbon depletion from the carbides, which indicates that the deviation of cementite’s chemical composition from the stoichiometric is the main reason for thermodynamic destabilisation of cementite during plastic deformation. Important results were obtained regarding the distribution of released carbon atoms in ferrite. It was experimentally confirmed that carbon segregates to the dislocations and grain boundaries of nanocrystalline ferrite. Another unusual phase transformation taking place in nanocrystalline pearlitic steel during room temperature HPT is a stress induced α→γ transformation, which never occurs during conventional deformation of coarse grained iron and carbon steels. It was concluded that this occurred due to a reverse martensitic transformation. The atomistic mechanism and the thermodynamics of the transformation, as well as issues related to the stability of the reverted austenite will be discussed.

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Fang, Feng, Xian Jun Hu, Shao Hui Chen, and Jian Qing Jiang. "Cementite Spheroidization of Drawn Wire during Isothermal Treatment." Applied Mechanics and Materials 80-81 (July 2011): 100–103. http://dx.doi.org/10.4028/www.scientific.net/amm.80-81.100.

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Lamellar cementite will be spheroidized in drawn pearlitic steel wire during galvanization process. To understand the evolution of the microstructure in this process, effects of isothermal time on microstructure of drawn pearlitic steel wires were investigated by using scanning electron microscope (SEM), transmission electron microscope (TEM) and DSC Technique. Experimental results showed that the lamellar cementite would transform to spheroidized cementite during the isothermal treatment. During the heating process, no endothermic or exothermic peak existed in pearlitic strand, while an obvious exothermic peak appeared in cold drawn pearlitic wire at about 380°C. It results from the spheroidization of lamellar cementite. The dislocation density was very low in pearlitic strand, but the dislocation density increased shapely after drawing. During the isothermal treatment at 450°C, the high dislocation density zone disappeared and some cementite became spheroidized. The cementite spheroidization phenomena first began at the boundary of pearlitic blocks or grains, and then in the high dislocation density zone in pearlitic blocks.

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Fonda, R. W., and M. V. Kral. "The Morphology of Widmanstatten Cementite Laths." Microscopy and Microanalysis 6, S2 (August 2000): 342–43. http://dx.doi.org/10.1017/s1431927600034206.

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The proeutectoid precipitation of Widmanstatten cementite has recently been shown to occur in two morphologies, either as broad monolithic plates or as aggregates of narrow laths, in a Fe-13 wt% Mn-1.3 wt% C steel, see Figure 1. Each of these morphologies correlates to a specific orientation of the cementite crystal within the austenite matrix; precipitates with a Pitsch orientation relationship adopt the monolithic plate morphology while precipitates with a Farooque-Edmonds orientation relationship develop as laths. In this paper, we examine the morphology and interfacial structure of these Widmanstatten cementite laths.The typical three-dimensional morphology of Widmanstatten cementite laths can be revealed by etching with a 10% nitric acid solution in methanol. This procedure selectively etches the austenite matrix without affecting the cementite precipitates (see Figure 1). By similarly etching an electropolished thin foil TEM sample, the three-dimensional morphology and internal structure of entire electron transparent cementite precipitates can be examined.

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Shiota, Y., A. Kanie, Yo Tomota, Stefanus Harjo, Atsushi Moriai, and Takashi Kamiyama. "Dissolution of Cementite Plates by Drawing, Re-Precipitation with Annealing and Corresponding Changes in Tensile Behavior in a Pearlite Steel." Solid State Phenomena 118 (December 2006): 27–30. http://dx.doi.org/10.4028/www.scientific.net/ssp.118.27.

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The microstructural change with drawing and subsequent annealing for a patented pearlite steel was investigated by means of neutron diffraction. The dissolution of cementite plates with drawing and re-precipitation of spherical cementite particles with annealing after sever drawing were observed. In situ neutron diffraction during tensile loading was performed and it is revealed that the strengthening mechanism of the specimen without cementite differs from that for a ferrite-cementite steel where the load transfer is a main mechanism. The possible strengthening mechanism for the heavily drawn specimen is proposed.

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Chakraborty, Jay, Tias Maity, Mainak Ghosh, Goutam Das, and Sanjay Chandra. "Cementite Dissolution in Cold Drawn Pearlitic Steel Wires: Role of Dislocations." Materials Science Forum 768-769 (September 2013): 304–12. http://dx.doi.org/10.4028/www.scientific.net/msf.768-769.304.

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Despite numerous investigations in the past, mechanism of cementite dissolution has still remained a matter of debate. The present work investigates cementite dissolution during cold wire drawing of pearlitic steel (~ 0.8wt% carbon) at medium drawing strain (up to true strain 1.4) and the role of dislocations in the ferrite matrix on the dissolution process. Quantitative phase analysis using x-ray diffraction (XRD) confirms more than 50% dissolution of cementite phase at drawing strain ~ 1.4. Detail analysis of the broadening of ferrite diffraction lines confirms presence of strain anisotropy in ferrite due to high density of dislocations (~ 1015m-2) at drawing strain 1.4. The results of the analysis shows that the screw dislocations near the ferrite-cementite interface are predominantly responsible for pulling the carbon atoms out of the cementite phase leading to its dissolution.

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Dlouhý, Jaromir, Daniela Hauserova, and Zbysek Novy. "Shape Evolution of Cementite during Accelerated Carbide Spheroidisation." Materials Science Forum 782 (April 2014): 117–22. http://dx.doi.org/10.4028/www.scientific.net/msf.782.117.

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Pearlite spheroidisation of 100CrMn6 steel was investigated. This process is well known and studied during conventional soft annealing. Presented paper describes cementite lamellae fragmentation during accelerated carbide spheroidisation. Mechanism of cementite lamellae fragmentation during conventional soft annealing depends on carbon and iron diffusion in ferrite-cementite system. On the other hand, accelerated carbide spheroidisation relies on partial pearlite austenitization and backward austenite decomposition. Aim of presented experiments was to examine shape evolution of cementite particles during transition from lamellar to globular form. Pearlite spheroidisation is normally quantified by image analysis of 2D metallographic section. Conventional metallographic observation was used for globular-lamellar particle ratio estimation. However, whole lamellae observation is necessary for spheroidisation process revelation. Ferrite matrix deep etching and cementite separation was performed to study morphological aspects of acceolerated carbide spheroidisation.

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Adachi, Nozomu, Haruki Ueno, Satoshi Morooka, Pingguang Xu, and Yoshikazu Todaka. "Deformation Texture of Bulk Cementite Investigated by Neutron Diffraction." Materials 15, no. 13 (June 25, 2022): 4485. http://dx.doi.org/10.3390/ma15134485.

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Understanding the deformation mechanism of cementite such as on a slip plane is important with regard to revealing and improving the mechanical property of steels. However, the deformation behavior of cementite has not been well investigated because of the difficulty of sample preparation given the single phase structure of cementite. In this study, by fabricating bulk single phase cementite samples using the method developed by the authors, the deformation texture formed by uniaxial compression was investigated using both electron back scatter diffraction and neutron diffraction. The fabricated sample had a random texture before the compression. After applying a compressive strain of 0.5 at 833 K, (010) fiber texture was formed along the compressive axis. It has been suggested from this trend that the primary slip plane of cementite is (010).

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Kim, Kwan Ho, Jae Seung Lee, and Duk Lak Lee. "Influence of Silicon on the Spheroidization of Cementite in Hypereutectoid Bearing Steels." Materials Science Forum 654-656 (June 2010): 154–57. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.154.

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The influence of silicon on the spheroidization of cementite in hypereutectoid 1.0C-1.45Cr bearing steels has been investigated, on the basis of microstructural analysis and thermodynamic calculations. The silicon content was varied 0.25 to 2.00 in weight percent. Annealed at 790∼850°C for 6 hr, the 0.25Si and 1.00Si steels were entirely spheroidized at 790°C, while 1.50Si and 2.00Si steels at 830°C, respectively. This implies that the increase of silicon content in hypereutectoid steels retards the spheoridization of cementite. The thermodynamic calculations revealed that silicon atoms were partitioned into not cementite but austenite at annealing temperatures, and the increase of silicon content can raise the chemical potential of carbon atoms within austenite at austenite/cementite interfaces, causing the decrease of driving force for the diffusion of carbon atoms from cementite to austenite.

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Adachi, Yoshitaka, and Yuan Tsung Wang. "Topology of Spheroidized Pearlite." Materials Science Forum 654-656 (June 2010): 70–73. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.70.

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Differential geometry and toplogy-based three-dimensional (3D) analysis was conducted to understand pearlite spheroidization mechanism in an eutectoid steel. Morphological change during aging below A1 tempearture was examined in terms of Gaussian(K)/mean curvatures(H), genus and Euler characteristics based on 3D images.The holes presentnaturally grown cementite lamella caused shape instability andinduced shape evolution of the lamellar structure during spheroidization. 3D visualization demonstrated that the intrinsic holes played an important role in the initiation and development of pearlitespheroidization. The hole coalescence and expansion causedthe breakup of large cementite lamellae into several long narrow ribbons. H-K plot actually suggested that the number of thses holes decreased with increasing aging period. In addition, small cementite particles and narrow rod cementite decreased during aging. These microstractural evolutions were discussed from the view point of ferrite/cementite interfacial energy.

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Umemoto, Minoru, and Hideyuki Ohtsuka. "Mechanical Properties of Cementite." Tetsu-to-Hagane 107, no. 4 (2021): 269–89. http://dx.doi.org/10.2355/tetsutohagane.tetsu-2020-114.

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Umemoto, Minoru, and Hideyuki Ohtsuka. "Mechanical Properties of Cementite." ISIJ International 62, no. 7 (July 15, 2022): 1313–33. http://dx.doi.org/10.2355/isijinternational.isijint-2022-048.

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Cottrell, A. H. "A theory of cementite." Materials Science and Technology 9, no. 4 (April 1993): 277–80. http://dx.doi.org/10.1179/mst.1993.9.4.277.

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Hallstedt, Bengt, Dejan Djurovic, Jörg von Appen, Richard Dronskowski, Alexey Dick, Fritz Körmann, Tilmann Hickel, and Jörg Neugebauer. "Thermodynamic properties of cementite ()." Calphad 34, no. 1 (March 2010): 129–33. http://dx.doi.org/10.1016/j.calphad.2010.01.004.

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Matteazzi, Paolo, Fibio Miani, and Gerard Le Caër. "Kinetics of cementite mechanosynthesis." Hyperfine Interactions 68, no. 1-4 (April 1992): 173–76. http://dx.doi.org/10.1007/bf02396464.

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Rożniata, Edyta, Janusz Krawczyk, Robert Dąbrowski, Marcin Madej, Łukasz Frocisz, and Jerzy Pacyna. "Microstructure and Tribological Properties of a Material with Cementite Eutectic Applied for Metallurgical Rolls." Key Engineering Materials 682 (February 2016): 119–24. http://dx.doi.org/10.4028/www.scientific.net/kem.682.119.

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Three prototype metallurgical rolls were produced on the basis of G200CrNiMo4-3-3 material. The method applied for the microstructure forming was different for each roll: the roll marked WOT – as cast state (without a modification and heat treatment); the metallurgical roll marked WMT – during its casting the FeCaSi deoxidizing was applied and then modification by a complex inoculant and argoning; the metallurgical roll marked WNT – subjected to a heat treatment (incomplete normalizing).The mentioned above differences in the technology of making rolls caused changes in their microstructure.The cementite eutectic and pearlitic matrix occurred in each roll. The main differences in the microstructure of cast steel rolls concerned a morphology of precipitates of hypereutectoid cementite. In the WOT roll cementite was mainly in the Widmannstӓtten system. Precipitates of hypereutectoid cementite in the WMT roll occurred along grain boundaries of primary austenite. A large fraction of spheroidal hypereutectoid cementite, precipitated in the whole volume of the primary austenite grain, appeared in the WNT roll. The microstructure influenced the rolls hardness and was equal 260 ÷ 350 HBW.Tribological investigations indicated decreasing the abrasive wear resistance with increasing the hypereutectoid cementite fraction within the primary austenite grains.

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Ciobanu, Mariana, Claudiu Nicolicescu, Stefan Radu, and Iulian Stefan. "Studies Regarding the Die Pressing Parameters on the Press Ability of Cementite Powders in Order to Obtained Sintered Steels." Advanced Materials Research 1128 (October 2015): 64–71. http://dx.doi.org/10.4028/www.scientific.net/amr.1128.64.

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This paper presents the experimental results of the effects of the pressing speed on the press ability of the cementite powders alloyed with iron powders, in order to obtain sintered steels. Cementite or iron carbide is a chemical compound with Fe3C formula having orthorhombic crystal structure. Regarding mechanical properties, cementite is hard and brittle being important in the metallurgical processes. For the research process was used a mixture consists by cementite and iron powders (6,75%Fe3C+93.25%Fe) which was obtained by mechanical alloying technique for 30 hours. The cementite powders were produced by direct carburizing of Fe powders. The mixture was unilateral die pressing at three pressures 200, 400 and 600 MPa respectively 5 pressing speeds 10 up to 50 mm/min. The green billets were sintered in argon atmosphere and were studied by microstructural point of view. The evolution of microhardness function the pressing parameters was studied too.

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Wang, Zhoutou, Qing Yuan, Zhicheng Zhang, Qingxiao Zhang, and Guang Xu. "Influence of Cementite Precipitation on Work Hardening Behavior in Ultrafine Grain Steels Rolled at Room and Cryogenic Temperatures." Metals 12, no. 11 (October 28, 2022): 1845. http://dx.doi.org/10.3390/met12111845.

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The work hardening behavior of α + θ UFG steel related to α + θ two phase microstructure is more complicated than that of single-phase materials. Very few studies have been conducted on the work hardening of α + θ UFG steels. Therefore, it is necessary to study the correlation between the work hardening and α + θ microstructure. In this study, the work hardening behavior of low-carbon ultrafine grain (UFG) steels with different grain size of ferrite and cementite particles, fabricated by rolling and annealing process, was studied. The α grain size was decreased to 132 ± 11 and 200 ± 19 nm in specimens cryorolled and annealed at 450 and 550 °C, which were smaller than that in specimen cold-rolled and annealed at 550 °C. However, the specimen cryorolled and annealed at 550 °C had a tensile strength of 740.3 MPa, which was lower than that in the other specimens. Results indicate that the work hardening is affected by ferrite and cementite in the UFG steels. The relatively coarse ferrite phase and the large number of fine intragranular cementite particles contribute to better work hardening. The intragranular cementite particles play a significant role in the improvement of work hardening, because the geometrically necessary dislocations are apt to form and store around intragranular cementite particles, while the intergranular cementite particles result in the decreased dislocation accumulation ability of ferrite and impair the strength of grain boundaries and work hardening of ferrite + cementite ultrafine grain steels.

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Levchenko, Elena V., Alexander V. Evteev, Irina V. Belova, and Graeme E. Murch. "Carbon Diffusion in Cementite: A Molecular Dynamics Study." Defect and Diffusion Forum 283-286 (March 2009): 24–29. http://dx.doi.org/10.4028/www.scientific.net/ddf.283-286.24.

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. In this paper, carbon diffusion in cementite is studied by molecular dynamics simulation. An assumption that carbon-carbon interaction occurs only indirectly via neighbouring iron atoms is used. An interstitial mechanism of carbon diffusion in cementite is revealed. The principal tracer diffusion coefficients and activation parameters of carbon diffusion in cementite are calculated for the temperature range 1223-1373 K and compared with the available published experimental data.

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Xiong, Yi, Tian Tian He, Fang Yu Zhang, Ling Feng Zhang, and Feng Zhang Ren. "Microstructure Evolution of Pearlitic Lamella Impacts at Ultra-High Strain Rates." Key Engineering Materials 464 (January 2011): 619–22. http://dx.doi.org/10.4028/www.scientific.net/kem.464.619.

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The microstructure evolution of eutectoid steel with lamellar pearlite was investigated by SEM and TEM during ultra-high strain rate loading. The results indicate that ultrafine microduplex structure (ferrite + cementite) with the grain size to sub-micrometer level was observed at the surface of eutectoid steel after single pass ultra-high strain rate loading. Equiaxed ferrite grain was about 0.8 μm and the cementite lamella was spheroidized fully, and the diameter of the cementite particle was about 50 nm. The bent or fractures can occur at the edge of shock wave. Ultra-high strain rate shocking induced severe plastic deformation at the surface of materials and the cementite lamella has better plastic deformation capacity.

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FURUKAWA, Shoji, Yu TAKANOHASHI, and Hisanori TANIYAMA. "612 Study on influence of heat treatment temperature on pro-eutectoid cementite and lamellar cementite : Possibility of micro device using cementite." Proceedings of Ibaraki District Conference 2007 (2007): 153–54. http://dx.doi.org/10.1299/jsmeibaraki.2007.153.

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Чулкина, А. А., А. И. Ульянов, В. А. Волков, А. Л. Ульянов, and А. В. Загайнов. "Влияние Cr и Ni на формирование фаз в механосинтезированном нанокомпозите на основе Fe-=SUB=-75-=/SUB=-C-=SUB=-25-=/SUB=-." Журнал технической физики 90, no. 5 (2020): 787. http://dx.doi.org/10.21883/jtf.2020.05.49180.154-18.

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X-ray diffraction, Mossbauer spectroscopy, and magnetic measurements have been used to study the phase formation and doping during mechanical synthesis (MS) and subsequent annealing of the alloy (Fe0.80Cr0.05Ni0.15)75C25. It has been shown that, after MS, the nanocomposite contains mainly two phases – an amorphous phase and cementite A. During annealing, as a result of crystallization of the amorphous phase, cementite B is formed, in which contains more nickel than in the mechanically synthesized cementite A. As the annealing temperature increases, austenite, which is inhomogeneous in nickel content, is formed. The Curie temperature of this austenite reaches 500 °C. It has been determined that cementite in the mechanosynthesized nanocomposite (Fe,Cr,Ni)75C25 has a higher temperature stabilitythan that in a MS composite (Fe,Ni)75C25.

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Serovaiskii, A. Yu, and V. G. Kutcherov. "The Stability of Cementite in the Presence of Water at Extreme Temperatures and Pressures." Chemistry and Technology of Fuels and Oils 632, no. 4 (2022): 39–42. http://dx.doi.org/10.32935/0023-1169-2022-632-4-39-42.

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The behavior of cementite (Fe3C) in aqueous environments was investigated in the thermobaric range of 180-950°C and 2-6 GPa. When interacting with water, cementite was transformed into wüstite and magnetite. The gaseous reaction products were represented mainly by saturated hydrocarbons with linear and branched structures up to C7. The composition of the hydrocarbon products synthesized from cementite and water at extreme thermobaric parameters varied from light mixtures similar to "dry" natural gasto complex hydrocarbon systems similar to "wet" natural gas and gas condensate. During the investigation, it was discovered that the chemical reaction between iron carbide and water begins at 220°C under extreme pressure, which is significantly lower than the temperature at which the reaction of cementite with water begins at ambient pressure.

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Kumar, Vinod, R. Balasubramaniam, and P. Kumar. "Microstructure Evolution in Deformed Ultrahigh Carbon Low Alloy (Wootz) Steel." Materials Science Forum 702-703 (December 2011): 802–5. http://dx.doi.org/10.4028/www.scientific.net/msf.702-703.802.

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The evolution of microstructure with degree of deformation in a deformed wedge shaped hypereutectoid steel implement, containing 1.84 C, 0.06 Si, 0.01 S, 0.14 P, 0.11 Cu, 0.017 Zr and 0.05 Ce, has been characterized using optical and scanning electron microscopy (SEM) and electron back scattered diffraction (EBSD). Microstructures consisted of bulky carbides dispersed in a matrix of pearlitic, with grain boundary proeutectoid cementite, side plate Widmanstatten cementite and intragranular cementite were noted in region of low strain. The cast structure was broken down with increasing degree of deformation. The mechanism for the formation of spheroidization of cementite in hypereutectoid steel has been proposed. Microstructural analysis of high strain region consists of fine equiaxed ferrite grains surrounded by high angle boundaries.

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Umemoto, Minoru, Yoshikazu Todaka, Akifumi Ohno, Mayumi Suzuki, and Koichi Tsuchiya. "Dissolution of Cementite in Carbon Steels by Heavy Deformation and Laser Heat Treatment." Materials Science Forum 503-504 (January 2006): 461–68. http://dx.doi.org/10.4028/www.scientific.net/msf.503-504.461.

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Dissolution behavior of cementite in eutectoid steels with pearlitic and spheroidite structures by severe plastic deformation was studied. Applying a long time milling, cementite dissolved completely and matrix turned out to be nanocrystalline ferrite. By a ball drop deformation (at high strain rates), heavily deformed layers in which cementite dissolves completely or partially were produced. By applying pulsed laser irradiation, re-austenitized zone which transformed to fresh martensite during quenching was produced. The boundary between the re-austenitized zone and matrix exhibited similar microstructure with that observed in specimens subjected to a ball drop deformation. It was suggested that the dissolution of cementite by heavy deformation at high strain rates are probably due to thermal effect, that is, re-austenitization.

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Czarski, A., T. Skowronek, and P. Matusiewicz. "Stability of a Lamellar Structure – Effect of the True Interlamellar Spacing on the Durability of a Pearlite Colony / Stabilność Struktury Płytkowej – Wpływ Rzeczywistej Odległości Międzypłytkowej Na Trwałość Kolonii Perlitu." Archives of Metallurgy and Materials 60, no. 4 (December 1, 2015): 2499–504. http://dx.doi.org/10.1515/amm-2015-0405.

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A lamellar microstructure is, beside a granular and dispersive one, the most frequently observed microstructure in the case of metal alloys. The most well-known lamellar microstructure is pearlite, a product of a eutectoidal transformation in the Fe-Fe3C system. The lamellar morphology of pearlite - cementite and ferrite lamellae placed interchangeably within one structural unit described as a colony - is dominant. The durability of the lamellar morphology is much diversified: in the microstructure of spheroidizingly annealed samples, one can observe areas in which the cementite is thoroughly spheroidized, next to very well-preserved cementite lamellae or even whole colonies of lamellar pearlite. The mentioned situation is observed even after long annealing times. The causes of such behaviour can vary. The subject of the previous work of the authors was the effect of the orientation between the ferrite and the cementite on the stability of the lamellar morphology. This work constitutes a continuation of the mentioned paper and it concerns the effect of the true interlamellar spacing on the stability of the lamellar morphology of cementite.

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Kraposhin, V. S., N. D. Simich-Lafitskiy, A. L. Talis, A. A. Everstov, and M. Yu Semenov. "Formation of the cementite crystal in austenite by transformation of triangulated polyhedra." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 75, no. 3 (May 10, 2019): 325–32. http://dx.doi.org/10.1107/s205252061900324x.

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A mechanism is proposed for the nucleus formation at the mutual transformation of austenite and cementite crystals. The mechanism is founded on the interpretation of the considered structures as crystallographic tiling onto non-intersecting rods of triangulated polyhedra. A 15-vertex fragment of this linear substructure of austenite (cementite) can be transformed by diagonal flipping in a rhombus consisting of two adjacent triangular faces into a 15-vertex fragment of cementite (austenite). In the case of the mutual austenite–cementite transformation, the mutual orientation of the initial and final fragments coincides with the Thomson–Howell orientation relationships which are experimentally observed [Thompson & Howell (1988). Scr. Metall. 22, 229–233] in steels. The observed orientation relationship between f.c.c. austenite and cementite is determined by a crystallographic group–subgroup relationship between transformation participants and noncrystallographic symmetry which determines the transformation of triangulated clusters of transformation participants. Sequential fulfillment of diagonal flipping in the 15-vertex fragments of linear substructure (these fragments are equivalent by translation) ensures the austenite–cementite transformation in the whole infinite crystal. The energy barrier for diagonal flipping in the rhombus with iron atoms in its vertices has been calculated using the Morse interatomic potential and is found to be equal to 162 kJ mol−1 at the face-centered cubic–body-centered cubic transformation temperature in iron.

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Lidyana, Roslan, Tetsuya Ohashi, Yohei Yasuda, Kohsuke Takahashi, and Chikara Suruga. "Finite Element Analyses of Elasto-Plastic Deformation in Pearlite Lamellar and Colony Structures." Key Engineering Materials 626 (August 2014): 307–10. http://dx.doi.org/10.4028/www.scientific.net/kem.626.307.

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Elasto-plastic tensile deformations in pearlite lamellar and two-colony structures are studied by finite element analyses to investigate the effects of lamellar thickness ratio and difference of lamellae orientation of two colonies in pearlite microstructure. The results obtained from plastic strain distributions in lamellar and colony structures show that plastic deformation in cementite lamellar stabilized when ferrite lamellar is thicker than cementite lamellar thickness and plastic strain concentrates when the difference between cementite lamellar orientation in two colonies are larger than 45°.

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Balak, Juraj, Xavier Sauvage, Duk Lak Lee, Choong Yeol Lee, and Philippe Pareige. "Cementite Decomposition of Pearlitic Steels during Cold Drawing." Advanced Materials Research 26-28 (October 2007): 45–50. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.45.

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Microstructures of cold drawn pearlitic steel wires were investigated by three-dimensional atom probe (3D-AP) to understand the influence of alloying elements on the decomposition of cementite. Before cold drawing, Si is mostly located in the ferrite phase, while Cr is located in the Fe3C phase and the amount of Mn is similar in Fe3C and in ferrite. Higher Si amount leads to higher dissolution rate of cementite and Cr has a little effect on cementite decomposition during drawing.

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Vogric, Marko, and Erwin Povoden-Karadeniz. "A multiscale mean field model for elastic properties of hypereutectoid pearlitic steels with different microstructures." International Journal of Materials Research 112, no. 5 (May 1, 2021): 348–58. http://dx.doi.org/10.1515/ijmr-2020-8039.

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Abstract Multiscale modeling of macroscopic elastic properties of pearlitic hypereutectoid steel using the Eshelby matrix–inclusion approach is possible. The model works through successive homogenization steps, based on the elastic properties of cementite and ferrite. Globular pearlite is homogenized using α Mori–Tanaka approach. Lamellar pearlite and pearlite colonies with fragmented proeutectoid cementite are homogenized by α classical self-consistent scheme. In the case of pearlite colonies surrounded by α continuous cementite film, α generalized self-consistent scheme is used. The influence of microstructural parameters such as the pearlite colony size or the thickness of the proeutectoid cementite on Young’s and shear moduli and on coefficients of the stiffness tensor is simulated. Proof of concept is obtained by comparison between predicted elastic behavior and experimental results from the literature.

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Zhang, Y. D., C. Esling, M. Calcagnotto, X. Zhao, and L. Zuo. "New insights into crystallographic correlations between ferrite and cementite in lamellar eutectoid structures, obtained by SEM–FEG/EBSD and an indirect two-trace method." Journal of Applied Crystallography 40, no. 5 (September 5, 2007): 849–56. http://dx.doi.org/10.1107/s0021889807032219.

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Four different ferrite/cementite orientation relationships (ORs) in near-eutectoid steel are derived using SEM–FEG/EBSD (scanning electron microscopy–field emission gun/electron back-scatter diffraction) and an indirect two-trace method. They show a common feature of close-packed plane parallelism between ferrite and cementite. Their crystallographic compatibility with habit planes shows a variety of possible habit planes and excludes the existence of the exact conventional Bagaryatsky and Pitsch–Petch ORs. Each of these new ferrite/cementite ORs is correlated with a different edge-to-edge matching condition between austenite and pearlitic ferrite, and between austenite and pearlitic cementite, and possesses specific morphological features. The present results may give deep insight into the crystallography of pearlitic transformation and provide useful information for materials design through interface tailoring in steels.

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Yin, Zhi Xin, and Harry Bhadeshia. "The Divorce Eutectoid Transformation in the Higher Mn Bearing Steel." Advanced Materials Research 634-638 (January 2013): 1798–802. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.1798.

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The detailed mechanism of divorced pearlite in bearing steels began to be actively discussed more recently. The survey of divorced pearlite in higher Mn bearing steel was carried out through scanning electronic microscope following isothermal transformation heat treatment. The results show that while divorced transformation taking place in the higher Mn bearing steel just slightly below A1, the cementite could be produced in such way as growing on the base of pre-existing cementite particles in austenite, or emerge either in globular particles or in short rod directly from the austenite. Under isothermal transformation, the carbon atoms in austenite prefer to precipitate on the original boundary of the austenite. The enough small size of the cementite particles remained in the austenite is helpful for getting spheroidal cementite particles structure through divorced eutectoid transformation.

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Ivanisenko, Julia, Witold Łojkowski, and Hans Jorg Fecht. "Stress- and Strain Induced Phase Transformations in Pearlitic Steels." Materials Science Forum 539-543 (March 2007): 4681–86. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.4681.

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An overview of the mechanically driven phase transformations taking place in nanocrystalline pearlitic steels in conditions of the severe plastic deformation (SPD), i.e. combination of high pressure and strong shear strains will be given. Conditions of the discussed experiments (room temperature and moderate strain rates) exclude any thermal origin of the observed transformations. One of them is strain induced cementite decomposition, which is a well-documented phenomenon taking place at cold plastic deformation of pearlitic steels. We explain this process taking into account friction forces at the interface between the hard cementite and ferrite. Under the high pressures and stresses higher than the ferrite matrix yield stress, the later one behaves like a viscoelastic fluid. The friction at the precipitate/matrix interface leads to two effects. One is to induce high strains on the precipitates. This leads to shift of thermodynamic equilibrium towards dissolution of the cementite. The second is wear of the cementite phase due to friction at the ferrite/cementite interface and mechanically induced drag of carbon atoms by the ferrite. This had been recently confirmed in 3D AP experiments, which demonstrated that the process of cementite decomposition starts with depleting of carbides with carbon and formation of non-stoichiometric cementite. The existing theories of atom drag by moving dislocations (ballistic models) can be regarded as one of the many possible mechanism of wear discussed by the wear theory. In that respect the process can be called athermal, as temperature indirectly influences wear processes but is not their main cause. We observed also another strain driven transformation in nanocrystalline pearlitic steel during room temperature high pressure torsion. This is a stress induced α→γ transformation, which has never been observed at conventional deformation of coarse grained iron and carbon steels. This was concluded to have occurred due to a reverse martensitic transformation.

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Antony, Ajesh, Natalya M. Schmerl, Anna Sokolova, Reza Mahjoub, Daniel Fabijanic, and Nikki E. Stanford. "Quantification of the Dislocation Density, Size, and Volume Fraction of Precipitates in Deep Cryogenically Treated Martensitic Steels." Metals 10, no. 11 (November 23, 2020): 1561. http://dx.doi.org/10.3390/met10111561.

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Two groups of martensitic alloys were examined for changes induced by deep cryogenic treatment (DCT). The first group was a range of binary and ternary compositions with 0.6 wt % carbon, and the second group was a commercial AISI D2 tool steel. X-ray diffraction showed that DCT made two changes to the microstructure: retained austenite was transformed to martensite, and the dislocation density of the martensite was increased. This increase in dislocation density was consistent for all alloys, including those that did not undergo phase transformation during DCT. It is suggested that the increase in dislocation density may be caused by local differences in thermal expansion within the heterogeneous martensitic structure. Then, samples were tempered, and the cementite size distribution was examined using small angle neutron scattering (SANS) and atom probe tomography. First principles calculations confirmed that all magnetic scattering originated in cementite and not carbon clusters. Quantitative SANS analysis showed a measurable change in cementite size distribution for all alloys as a result of prior DCT. It is proposed that the increase in dislocation density that results from DCT modifies the cementite precipitation through enhanced diffusion rates and increased cementite nucleation sites.

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Jiang, Tao, Shizhong Wei, Liujie Xu, Cheng Zhang, Xiaodong Wang, Mei Xiong, Feng Mao, Long You, and Chong Chen. "Effect of Microstructures on the Tribological Performance of Medium Carbon Steel." Metals 12, no. 4 (March 23, 2022): 546. http://dx.doi.org/10.3390/met12040546.

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Improving wear resistance and reducing the coefficient of friction of the cylinder liner are critical to improving the service life and energy savings of internal combustion engines. In this paper, the effect of the characteristics of cementite precipitation on the tribological performance was studied using a medium carbon steel (AISI 1045 steel), which can be used to make cylinder liners. Three kinds of microstructures with different characteristics of cementite were obtained by heat treatments. Abrasive wear tests and dry sliding friction tests were conducted on the samples of each microstructure. The study indicated that the abrasive wear resistance of medium carbon steel mainly depends on its hardness rather than on the characteristics of cementite precipitation. However, increasing the hardness alone did not guarantee improvement of the dry sliding friction performance of medium carbon steel. The specimen with a spherical pearlite microstructure, which was granular cementite distributed in the ferrite matrix showed the best friction performance. Moreover, the abrasive wear mechanism and dry sliding friction mechanism were discussed. In the end, the correlation between the characteristics of cementite and tribological behavior was established. These findings can help develop multiphase materials with outstanding tribological performance.

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Journal articles on the topic 'Cementite'

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