开放存取 开放存取  受限制的访问 ##reader.subscriptionAccessGranted##  受限制的访问 订阅存取

卷 59, 编号 7-8 (2017)

Transformations

Effect of Microalloying of Roll Steel 70Kh3G2VTB on the Kinetics of Phase Transformations and Fine Structure Under Crystallization and Heat Hardening

Krylova S., Fot A., Gryzunov V., Firsova N.

摘要

Decomposition of supercooled austenite in steel 70Kh3G2VTB under continuous cooling is investigated. The thermokinetic diagram of decomposition of austenite in the pilot steel is plotted. The temperature-time ranges of the structural transformations are obtained. The effect of the parameters of austenitizing on the processes of dissolution of the carbide phase under heating is described. The fine structure of the pilot steel is studied in different stages of heat hardening.

Metal Science and Heat Treatment. 2017;59(7-8):399-406
pages 399-406 views

Inverse Martensitic α → γ Transformation in Nanostructured Maraging Steels

Makhneva T., Sukhikh A., Dement’ev V.

摘要

The critical temperature (As) of the start of heating-induced α → γ phase transformation has been determined in two nanostructured maraging steels. It is established that, irrespective of the method of nanostructure formation and dimensions of structure constituents within the range studied, the As value of the inverse martensitic transformation decreases so as to fall in the interval of aging temperatures. Special features of the development of α → γ phase transformation in the hardened matrix are determined. Factors favoring the decrease in As are analyzed and the results of investigations are generalized.

Metal Science and Heat Treatment. 2017;59(7-8):473-478
pages 473-478 views

Article

Effect of Thermocycling on the Structure of Martensite and Kinetics of Martensitic Transformation in Alloy Fe – 30% Ni – 3% Pd

Yildiz Y., Yildiz G.

摘要

The methods of scanning electron microscopy, differential scanning calorimetry and x-ray diffraction are used to study the morphological and thermal characteristics of cooling-induced martensite in alloy Fe – 30% Ni – 3% Pd. It is shown that the kinetics of the martensitic transformation is athermal and the morphology is lamellar. The mean values of the parameters of the austenite and martensite lattices are 0.35704 and 0.28614 nm respectively. The thermocycling leaves the points As and Af invariable.

Metal Science and Heat Treatment. 2017;59(7-8):407-409
pages 407-409 views

Inheritance of the Elastic Field of Martensite Nucleation Center by the Control Wave Process Initiating Deformations of Planes {110}c of Cubic Crystals

Kashchenko M., Chashchina V.

摘要

The possibility of inheritance of the elastic field in the zone of appearance of the initial excited state by the wave process controlling growth of the martensite crystal is shown. The case when the wave vectors of the control waves belong to plane {110}c of the original cubic phase is analyzed. Implementability of such inheritance is demonstrated with the use of elastic moduli for single-crystal bcc titanium, which advances the predictive capacity of the dynamic theory.

Metal Science and Heat Treatment. 2017;59(7-8):410-414
pages 410-414 views

Effect of Neodymium and Zirconium on the Structure of Castable Magnesium Alloy ML10 (NZ30K)

Koltygin A., Bazhenov V., Nikitina A.

摘要

Alloys of the Mg – Zn – Zr – Nd system with composition matching that of ML10 (NZ30K) and different contents of the main alloying components within the standardized range are studied. Four-component Mg – Zn –Zr – Nd phase diagrams are simulated, and the stages of crystallization of the alloys are considered. The structure of the alloys is determined in cast condition and after a T6 heat treatment. Fracture surfaces are analyzed. The distribution of the alloying elements in the structure is studied. The changes in the content of zirconium within the standardized range are shown to affect the grain size in the cast and heat treated states.

Metal Science and Heat Treatment. 2017;59(7-8):422-428
pages 422-428 views

Effect of Extrusion-Sheer on the Microstructure and Mechanical Properties of Magnesium Alloy AZ31

Hu H., Sun Z., Qing S., Zhang D., Yang M.

摘要

The effect of extrusion combined with shear (ES) on the microstructure and mechanical properties of magnesium alloy AZ31 is studied. The additional die providing shear deformation of the extruded bars (two successive turns of the calibrating channel to equal opposite angles) provides refinement of grains. Growth of the deformation temperature causes grain growth. The intensity of the x-ray reflection from basal plane (0002) after the ES increases. After the deformation at 420°C fracture mainly develops by the transgrain mechanism. After the deformation at 450°C the maximum hardness corresponds to the largest grain size in the central part of the bar, and the fracture is chiefly determined by twinning.

Metal Science and Heat Treatment. 2017;59(7-8):429-432
pages 429-432 views

Relaxation Resistance of Spring Strips from Austenitic-Ferritic Steel 03Kh13N10K5M2Yu2T

Levina A., Mal’tseva L., Ozerets N., Mal’tseva T., Asanova D.

摘要

The mechanical and relaxation properties of corrosion-resistant aluminum-containing austenitic-ferritic steel 03Kh13N10K5M2Yu2T are considered as a function of the mode of preliminary thermoplastic treatment and its temperature-time conditions.

Metal Science and Heat Treatment. 2017;59(7-8):441-445
pages 441-445 views

Effect of Low-Cycle Thermocycling Treatment on Corrosion and Mechanical Properties of Corrosion-Resistant Steel 12Kh18N10T Irradiated with Neutrons

Yarovchuk A., Maksimkin O., Tsay K.

摘要

The effect of thermocycling treatment on the susceptibility to local corrosion and mechanical characteristics of corrosion-resistant steel 12Kh18N10T in different states (after austenitizing, cold rolling, and neutron irradiation) is considered. The possibility of partial recovery of the corrosion and mechanical characteristics of irradiated reactor steel due to low-cycle thermocycling in a temperature range exceeding the irradiation temperature is demonstrated.

Metal Science and Heat Treatment. 2017;59(7-8):446-453
pages 446-453 views

Fabrication of Intermetallic Titanium Alloy Based on Ti2AlNb by Rapid Quenching of Melt

Senkevich K., Serov M., Umarova O.

摘要

The possibility of fabrication of rapidly quenched fibers from alloy Ti – 22Al – 27Nb by extracting a hanging melt drop is studied. The special features of the production of electrodes for spraying the fibers by sintering mechanically alloyed powdered components of the alloy, i.e., titanium hydride, niobium, and aluminum dust, are studied. The rapidly quenched fibers with homogeneous phase composition and fine-grained structure produced from alloy Ti – 22Al – 27Nb are suitable for manufacturing compact semiproducts by hot pressing.

Metal Science and Heat Treatment. 2017;59(7-8):463-466
pages 463-466 views

Martensitic Transformation in Low-Carbon Steels

Bykova P., Larinin D., Berezin S., Shatsov A.

摘要

Isothermal and thermokinetic martensitic transformations in low-carbon martensitic steels have been studied. Amodel is proposed that relates the mechanical state of the austenite, as dependent on the parameters of thermal treatment and the law of the grain size distribution, to the volume fraction of transformed martensite. Physical constants of the transformation are determined.

Metal Science and Heat Treatment. 2017;59(7-8):479-485
pages 479-485 views

Transformations of Supercooled Austenite in a Promising High-Strength Steel Grade Under Continuous Cooling Conditions

Maisuradze M., Ryzhkov M., Yudin Y., Kuklina A.

摘要

Special features of the transformations of supercooled austenite occurring under continuous cooling of a promising high-strength steel grade not standardized in the Russian Federation are determined. A method for evaluating the volume fractions of structure constituents formed in the steel as a result of cooling from 925°C at various constant rates within 0.025 – 75 K/sec is proposed and tested. The results are generalized in the form of a thermokinetic diagram of transformations of supercooled austenite.

Metal Science and Heat Treatment. 2017;59(7-8):486-490
pages 486-490 views

Crack Resistance of an Alloy of the Al – Cu – Mg – Ag System

Zhemchuzhnikova D., Gazizov M., Kaibyshev R.

摘要

Cyclic crack resistance of an aluminum alloy of the Al – Cu – Mg – Ag system with a high content of doping elements is studied. It is shown that the alloy possesses a high threshold value of the stress intensity factor for nucleation of fatigue cracks. However, the nonuniform distribution of second-phase particles in the material reduces the crack resistance. Special features and main differences of the relief of fatigue fracture surfaces of the alloy in various regions of the kinetic diagram are considered. Coefficients of the Paris’ equation for the region of linear fatigue-crack growth are determined.

Metal Science and Heat Treatment. 2017;59(7-8):498-503
pages 498-503 views

Softening and Hardening of Alloys of the Al – Zn System Under Plastic Deformation

Skvortsov A., Polev V.

摘要

The proportion of hardening and softening under plastic deformation at room temperature in metals and alloys of the Al – Zn system has been studied as dependent on the regime of preliminary heat treatment. The influence of the strain rate on the dependence of alloy hardness on the degree of plastic deformation is estimated.

Metal Science and Heat Treatment. 2017;59(7-8):504-508
pages 504-508 views

Effect of Zircon Particle Size on Age Hardening Behavior of A356 Alloy Based Composites

Satish Kumar T., Subramanian R., Shalini S., Gowrishankar A., Angelo P.

摘要

Melt stirring was used to introduce various amounts of zircon (ZrSiO4) particles of various sizes into aluminum alloy A356 of the Al – Si system. The effect of zircon particle sizes on age hardening behavior of stir-cast A356 alloy/zircon reinforced composites was studied by measuring microhardness after solution treatment and aging for various times. The structure of composites was studied by methods of optical microscopy, x-ray diffraction, scanning electron microscopy combined with energy dispersive x-ray spectroscopy, and high-resolution transmission electron microscopy. The addition of zircon was found to accelerate age hardening of the matrix alloy. It is established that the maximum hardness increases and the time of attaining this maximum decreases with growing content of zircon particles and with reduction in their average size.

Metal Science and Heat Treatment. 2017;59(7-8):509-512
pages 509-512 views

Special Features of the Structure of Laser-Welded Joints of Dissimilar Alloys Based on Titanium and Aluminum

Nikulina A., Smirnov A., Turichin G., Klimova-Korsmik O., Babkin K.

摘要

The structure of laser-welded joints of parts having different thicknesses fabricated from alloys based on aluminum and titanium has been studied. Results of transmission and scanning electron microscopy measurements and x-ray diffraction analysis show that the diffusion interaction of microvolumes of two alloys in the weld leads to the formation of two interlayers: (i) a continuous intermetallic TiAl layer with thickness below 1 μm adjacent to the titanium alloy and (ii) a layer consisting of TiAl3 intermetallic dendrites with thickness of 2 – 6 μm adjacent to the TiAl layer. The average microhardness of the intermetallic layer is about 490 HV.

Metal Science and Heat Treatment. 2017;59(7-8):534-539
pages 534-539 views

Mechanical Properties of Steel P92 Welded Joints Obtained By TIG Technology

Mohyla P., Havelka L., Schmidová E., Vontorová J.

摘要

Mechanical properties of P92 steel welded joints obtained using the TIG (141) technology have been studied upon post-welding heat treatment (PWHT). The microhardness, tensile strength, and impact toughness of metal in the weld and heat-affected zone are determined. The PWHT is shown to be obligatory.

Metal Science and Heat Treatment. 2017;59(7-8):540-542
pages 540-542 views

Magnesium Alloys

Effect of REE on the Phase Composition and Properties of a New Refractory Magnesium Alloy of the Mg – Zn – Zr – REE System

Kablov E., Volkova E., Filonova E.

摘要

A novel high-strength refractory alloy VMD16 of the Mg – Zn – Zr – REE system is described. The advantages of the alloy with respect to the counterparts are considered. The processes of formation of phase composition and of structural evolution are studied. A fine dispersed subgrain structure is shown to exist in the deformable magnesium alloy. The combination of the specific morphology and topology of the intermetallic phases with their thermal stability provides a high level of strength properties at room and elevated (300 – 350°C) temperatures at a low anisotropy.

Metal Science and Heat Treatment. 2017;59(7-8):415-421
pages 415-421 views

Corrosion-Resistant Steels

Effect of Thermal Fields on the Structure of Corrosion-Resistant Steels Under Different Modes of Laser Treatment

Tarasova T., Gusarov A., Protasov K., Filatova A.

摘要

The influence of temperature fields on the structure and properties of corrosion-resistant chromium steels under different modes of laser treatment is investigated. A model of heat transfer under laser impact on target is used to plot thermal fields and cycles and cooling rates. It is shown that the model used for computing thermal fields gives tentative geometric sizes of the fusion zones under laser treatment and selective laser fusion. The cooling rate is shown to have decisive influence on the structure of corrosion-resistant steels after laser treatment with surface fusion in devices for pulsed, continuous, and selective laser melting.

Metal Science and Heat Treatment. 2017;59(7-8):433-440
pages 433-440 views

Aluminum and Titanium Alloys

Mechanical and Life Properties of Sheets from Alloys of the Al – Mg – Sc System

Shvechkov E., Filatov Y., Zakharov V.

摘要

The characteristics of strength, static crack resistance, rate of growth of fatigue cracks and cyclic endurance of annealed sheets from weldable alloys of the Al – Mg – Sc system are studied as compared to annealed sheets from alloy AMg6. The compositions of aluminum alloys with scandium (01545 and 1570S) with characteristics substantially superior to those of AMg6 and level of properties comparable to that of the base aircraft not weldable alloy 1163 in state T6 are determined.

Metal Science and Heat Treatment. 2017;59(7-8):454-462
pages 454-462 views

Technical Information

Effect of the Fractional Composition of Filler Powder and Parameters of Laser Coaxial Surfacing on Formation of Beads

Noskov A., Yanbaev R., Shamsrakhmanov T., Mannanov I., Kadyrov I.

摘要

An experimental study of the morphology of particles of a filler powder and of the characteristics of beads produced by laser gas-powder surfacing is performed. The main laws of formation of bead in the course of laser surfacing are determined. The optimum modes of deposition onto a substrate from steel 09G2S are suggested.

Metal Science and Heat Treatment. 2017;59(7-8):467-470
pages 467-470 views

Aluminum Alloys

Effect of Homogenizing Heat Treatment of Liquid Aluminum–Copper Alloys on the Structure of Rapidly Crystallized Specimens

Astaf’ev V., Kurochkin A., Yablonskikh T., Brodova I., Popel’ P.

摘要

Centrifugal casting into a massive slot chill mold was used to prepare two series of specimens of alloys of the Al – Cu system, containing from 10 to 32.2 at.% Cu. The first series was fabricated without a homogenizing heat treatment of the melt, while the second series was fabricated with heating of the melt to 1400°C. Both kinds of specimens were cast at the same temperature in order to provide for the same cooling rate of about 104 K/sec. The structures, phase compositions and microhardnesses of the structural components are compared. It is established that the homogenizing heat treatment changes the kinetics of crystallization and, hence, the proportion of phases in the alloy structure and the copper content in them.

Metal Science and Heat Treatment. 2017;59(7-8):491-497
pages 491-497 views

Refractory and Magnesium Alloys

Formation of the Structure of a Eutectic Alloy of the Nb – Si System During Directed Crystallization with Liquid-Metal Coolant

Bondarenko Y., Echin A., Kolodyazhnyi M., Surova V.

摘要

Peculiarities of the structure of a refractory eutectic alloy of the Nb – Si system, formed by the method of directed crystallization with liquid-metal coolant, have been studied. Characteristic zones of microstructure of the ingot obtained upon directed crystallization are considered, the alloy composition is analyzed, and volume fractions of phases in the Nb – Si composite are determined.

Metal Science and Heat Treatment. 2017;59(7-8):513-517
pages 513-517 views

Formation of High-Coercivity State in Fe2NiAl Alloy During Decomposition of Solid Solution Under Quenching from Liquid State and Subsequent Annealing

Menushenkov V., Gorshenkov M., Savchenko E., Shchetinin I., Savchenko A.

摘要

The methods of transmission electron microscopy, atomic force microscopy, x-ray diffraction, and magnetic measurements were used to study the laws of formation of the microstructure and magnetic properties in Fe2NiAl (alni) alloy after quenching from liquid state and subsequent annealing at 500 – 780°C. The microstructure of rapidly hardened flakes is characterized by the presence of inhomogeneities less than 10 nm in size and boundaries of anti-phase domains. Annealing of the flakes is accompanied by their discontinuous decomposition, which causes growth of the colonies comprising alternating plates of β and\( {\upbeta}_2^{\prime } \) phases on grain boundaries.

Metal Science and Heat Treatment. 2017;59(7-8):518-523
pages 518-523 views

Thermochemical Treatment

The Influence of High-Pressure Gas Nitriding on the Properties of Martensitic Steels

Alekseeva M., Gress M., Scherbakov S., Gerasimov S., Kuksenova L.

摘要

The influence of high-pressure gas nitriding on the structure and properties of martensitic steels VKS-5, VKS-7, 20Kh3N3MFB, and 25Kh5M is investigated. It is shown that the high-pressure nitriding increases the thickness of the diffusion zone at substantial reduction of the process time as compared to the traditional gas-phase nitriding. Increase of the post-treatment cooling rate above 30 K/min favors the formation of diffusion layers with greater hardness.

Metal Science and Heat Treatment. 2017;59(7-8):524-528
pages 524-528 views

Welded Joints

A Study of the Structure of Steel – Titanium Joints Formed by Diffusion Welding with the Use of Ultrafine Nickel Powder

Uvarov A., Semenov A., Krestnikov N., Lyushinskii A., Nikitina E.

摘要

The structure and phase composition of welded joints of austenitic steel 08Kh17N10T and titanium alloy PT-3V formed by diffusion welding with an intermediate layer of ultrafine nickel powder have been studied. The microstructure of joints welded in various regimes was studied using metallographic and energy-dispersive x-ray microanalysis techniques. Good prospects of the application of ultrafine dispersed media for diffusion welding of steels and titanium alloys are shown.

Metal Science and Heat Treatment. 2017;59(7-8):529-533
pages 529-533 views