Features of the structure with static strain aging of an austenitic corrosion-resistant steel

Conclusion The data provided clearly point to the complex nature of static strain aging for steel type Kh16N15 which depends significantly on the degree of prior deformation. The shape of carbides formed is determined by the degree of prior deformation and it changes from acicular (in austenitized specimens) to lamellar (in lightly worked specimens) and a circular shape (in strongly worked specimens).Novopolotsk Polytechnic Institute. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 39–40, July, 1988.     

Carbides in atomized powder and powder tungstenless high-speed steel

Carbides are necessary component part of the structure in high-speed steels. The wear resistance, heat resistance, and strength of these steels markedly depend on the amount of carbides, the ratio between different types of carbides, and their states. The aim of the present work is to study the phase composition of carbide precipitates obtained from atomized powder and the corresponding tungstenless powder high-speed steel of the type M5F5.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 6, pp. 23–26, June, 1994.     

Features of the microstructure of 20GL steel

Conclusion Manganese has a significant influence on the structure formation and properties of 20GL steel. With a content of more than 0.6% manganese promotes the formation of a lamellar bainitic structure consisting of ferrite and microzones of residual austenite or products of its decomposition. In individual cases these microzones may be competely isolated from one another but more frequently, apparently, they form a branched skeleton of ferrite grains. Such a microstructure of heterogenized ferrite grains provides a marked effect of microcomposition strengthening of steel.With a higher manganese content in the steel the residual austenite may remain in the form of edges on the ferritic grain boundaries. This causes significant embrittlement of the steel, especially at low temperatures. In 20GL, 20TL, and 20GFL steels with a content of up to 1.4% Mn areas with austenite edges are rarely observed and do not cause significant embrittlement of the steel.In describing and standardization of the microstructures and evaluation of the mechanical and service properties of parts of 20GL steel it is necessary to take into consideration the nonuniformity of the structure and properties across the section of heat treated castings.Deceased.Bryansk Technological Institute, Bezhetsk Steel Casting Plant. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 11, pp. 27–31, November, 1986.     

连铸稀土钢用结晶器保护渣

论述稀土钢连铸的特点及其结晶器保护渣的特性，提出改善连铸稀土钢用结晶器保护渣使用性能的措施。对提高稀土钢连铸坯质量具有一定的意义。     

Contact fatigue strength of powder steel ShKh15

Conclusion The contact longevity of powder steel ShKh15, as determined from tests conducted in accordance with the AXMAT scheme, approaches the same characteristic of the cast steel, and exceeds it significantly in tests conducted in accordance with the R-MAT method. The latter is associated with the finer structure and higher strength properties of powder as compared with the cast steel ShKh15.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 8, pp. 56–58, August, 1990.     

Correction of the structure of cast steel

Metal Science and Heat Treatment -     

Features of deformed austenite transformation under isothermal conditions with thermomechanical treatment of steel into a pearlitic structure

Considerable attention is currently being devoted to softening thermomechanical treatment of structural steels during which a pearlite structure forms (TMTp). This interest is due to the fact that an overwhelming proportion of rolled sections and forgings is subjected to softening heat treatment (as a rule with separate heating) in order to provide the required technological properties in manufacturing machine components (deformability in the cold state, inachinability, etc.). With TMTp of a rolled product (a casting) the softening heat treatment is combined in one process. Results are given in this article for a study of the transformation of deformed austenite in various alloy steels.I. P. Bardin Scientific Research Institute of Ferrous Metallurgy (TsNIIChERMET). Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 11, pp. 4–8, November, 1994.     

Interaction of powder microparticles with the steel matrix under dynamic action

Conclusions In dynamic interaction of powder particles and the steel matrix at the points of their retarding and stoppage, significant high-velocity plastic deformation occurs according to shear, rotational, and twinning mechanisms, which, together with local microalloying of the matrix with elements of the particles, promotes additional hardening of the steel. Processes of complete restoration of the structure in these areas are undesirable since they reduce the effect of hardening of the steel with dispersed particles.Dnepropetrovsk Metallurgical Institute. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 44–45, February, 1991.     

一种粉末冶金铁素体钢中的双组态结构(英文)

采用混合预合金粉末和球磨粉末的方法,制备一种具有双组态结构的铁素体合金钢,其名义成分为Fe-14Cr-3W-0.42Ti-0.32Y。其微观组织与成分相同但是采用全球磨粉末成形的铁素体钢有明显的区别。通过热锻、空冷之后,该合金具有铁素体晶粒和马氏体晶粒混合构成的双组态结构。通过微观组织研究发现了在该合金中发生了局部的αbcc→γfcc→α'bcc相变。同时,这种双组态结构能够较好地均衡合金的强度和韧性。     

Selective laser sintering of single-phase powder Cr-V tool steel

Presented is positive experience from selective laser sintering (SLS) of cylindrical steel specimens (3.0% C, 3.0% Cr, 1.0% Si, 12.0% V, Fe balance) 30 mm long and 5 mm in diameter by rapid prototyping. It was demonstrated that monolithic steel material could be successfully fabricated by this technology. Differential thermal analysis (DTA), scanning electron microscopy (SEM), and x-ray diffractometry (XRD) were used to study the microstructure, phase, and chemical composition of the source material and obtained specimens. Low-melting cementite-based eutectic was found to provide the liquid phase sintering of powder tool steel. The porosity of the green sintered specimens did not exceed 5%. The mean hardness value of sintered specimens was 825 HV.