Heat treatment of outer races of conical roller bearings in a grooved quenching-and-tempering unit

1995 ◽  
Vol 37 (3) ◽  
pp. 113-114
Author(s):  
L. A. Koshcheeva ◽  
N. P. Protasevich
Keyword(s):  
Heat Treatment ◽  
Roller Bearings ◽  
Quenching And Tempering ◽  
Conical Roller

INFLUENCE THE QUENCHING AND TEMPERING ON THE MICROSTRUCTURE, MECHANICAL PROPERTIES AND SURFACE ROUGHNESS, OF MEDIUM CARBON STEEL

2018 ◽  
Vol 18 (1) ◽  
pp. 125-135
Author(s):  
Sattar H A Alfatlawi
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Surface Roughness ◽  
Carbon Steel ◽  
Cold Water ◽  
Medium Carbon Steel ◽  
Medium Carbon ◽  
Heating And Cooling ◽  
Treatment Processes ◽  
Quenching And Tempering

One of ways to improve properties of materials without changing the product shape toobtain the desired engineering applications is heating and cooling under effect of controlledsequence of heat treatment. The main aim of this study was to investigate the effect ofheating and cooling on the surface roughness, microstructure and some selected propertiessuch as the hardness and impact strength of Medium Carbon Steel which treated at differenttypes of heat treatment processes. Heat treatment achieved in this work was respectively,heating, quenching and tempering. The specimens were heated to 850°C and left for 45minutes inside the furnace as a holding time at that temperature, then quenching process wasperformed in four types of quenching media (still air, cold water (2°C), oil and polymersolution), respectively. Thereafter, the samples were tempered at 200°C, 400°C, and 600°Cwith one hour as a soaking time for each temperature, then were all cooled by still air. Whenthe heat treatment process was completed, the surface roughness, hardness, impact strengthand microstructure tests were performed. The results showed a change and clearimprovement of surface roughness, mechanical properties and microstructure afterquenching was achieved, as well as the change that took place due to the increasingtoughness and ductility by reducing of brittleness of samples.

Network Carbide Inheritance during Heat Treatment Process of Large Shield Machine Bearing Steel GCr15SiMn

2015 ◽  
Vol 817 ◽  
pp. 115-120 ◽  
Author(s):  
Dan Zhang ◽  
Le Yu Zhou ◽  
Chao Lei Zhang ◽  
Chao Huang ◽  
Min Zhao ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Treatment Process ◽  
Bearing Steel ◽  
Treatment Temperature ◽  
Heat Treatment Process ◽  
Soaking Time ◽  
Hot Rolled ◽  
Chinese Standard ◽  
Shield Machine ◽  
Quenching And Tempering

Network carbide inheritance during heat treatment process of large shield machine bearing steel GCr15SiMn was investigated by heat treatment experiments and quantitative metallographic. Samples with the proeutectoid cementite network thickness in the range of 0.19~0.54 μm were obtained by changing austenitizing temperature and soaking time of pearlite transformation. The results show that the network in hot rolled bar can be improved when the pre-heat treatment temperature is 950 °C. When the network thickness is above 0.40 μm, the undissolved cementite networks present in microstructures after quenching and tempering. In a Chinese standard, the network grades are 1.5 and 3.0 degree when the networks thickness are 0.40 μm and 0.54 μm, respectively. The critical network thickness that can be eliminated by heat treatment is 0.29 μm.

scholarly journals Austenite Reversion Tempering-Annealing of 4 wt.% Manganese Steels for Automotive Forging Application

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 575 ◽  
Author(s):  
Alexander Gramlich ◽  
Robin Emmrich ◽  
Wolfgang Bleck
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Chemical Composition ◽  
Impact Toughness ◽  
Temperature Control ◽  
Annealing Process ◽  
Air Cooling ◽  
Metastable Austenite ◽  
Quenching And Tempering ◽  
Manganese Steels

New medium Mn steels for forged components, in combination with a new heat treatment, are presented. This new annealing process implies air-cooling after forging and austenite reversion tempering (AC + ART). This leads to energy saving compared to other heat treatments, like quenching and tempering (Q + T) or quenching and partitioning (Q + P). Furthermore, the temperature control of AC + ART is easy, which increases the applicability to forged products with large diameters. Laboratory melts distinguished by Ti, B, Mo contents have been casted and consecutively forged into semi-finished products. Mechanical properties and microstructure have been characterized for the AC and the AC + ART states. The as forged-state shows YS from 900 MPa to 1000 MPa, UTS from 1350 MPa to 1500 MPa and impact toughness from 15 J to 25 J. Through the formation of nanostructured retained metastable austenite an increase in impact toughness was achieved with values from 80 J to 100 J dependent on the chemical composition.

Microstructure and Mechanical Properties of High Strength Alloyed Steel for Aerospace Application

2018 ◽  
Vol 284 ◽  
pp. 351-356 ◽  
Author(s):  
Mikhail V. Maisuradze ◽  
Maksim A. Ryzhkov
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
High Strength ◽  
Single Stage ◽  
The Novel ◽  
Tempering Temperature ◽  
Quenching And Partitioning ◽  
Aerospace Application ◽  
Cooling Conditions ◽  
Quenching And Tempering

The high strength aerospace steel alloyed with Cr, Mn, Si, Ni, W and Mo was studied. The austenite transformations under continuous cooling conditions were investigated using the dilatometer analysis at the cooling rates 0.1...30 °C/s. The mechanical properties of the studied steel were determined after the conventional quenching and tempering heat treatment. The dependences of the mechanical properties on the tempering temperature were obtained. The novel quenching and partitioning heat treatment was applied to the steel under consideration. The microstructure and the mechanical properties were studied after three different modes of the quenching and partitioning (QP) treatment: single-stage QP, two-stage QP and single-stage QP with subsequent tempering (QPT).

Optimization for Heat Treatment Process of Supercritical Material F92Steel

2011 ◽  
Vol 142 ◽  
pp. 95-98
Author(s):  
Jian Sheng Ding ◽  
Lin Xun Liu ◽  
Jin Chun Feng
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
High Temperature ◽  
Treatment Process ◽  
Rupture Strength ◽  
Lath Martensite ◽  
Precipitation Strengthening ◽  
Heat Treatment Process ◽  
Fully Integrated ◽  
Quenching And Tempering

The supercritical material F92 steel is regarded as the research object, and the influence law of heat treatment process on its tissue and properties is analyzed. The results show that when the temperature of heat treatment quenching and tempering is too low, a large number of alloying elements cannot be fully integrated into the austenite, and the optimal obdurability of F92 steel is still not fully exploited; while too high temperature of heat treatment quenching and tempering will weaken the strength, plasticity and toughness. When F92 steel is processed by heating quenching at 1050 °C and tempering at 680 °C, its tissue is the smaller tempered lath martensite. The carbide is precipitated, generating precipitation strengthening, which gives it a high rupture strength and toughness. F92 steel is with high mechanical properties when heating quenched at 1050 °C and tempered 680 °C.

Effect of Heat Treatment Technique on the Low Temperature Impact Toughness of Steel EQ70 for Offshore Structure

2017 ◽  
Vol 36 (8) ◽  
pp. 825-830 ◽  
Author(s):  
Su-Fen Tao ◽  
Yun-Jin Xia ◽  
Fu-Ming Wang ◽  
Jie Li ◽  
Ding-Dong Fan
Keyword(s):  
Heat Treatment ◽  
Low Temperature ◽  
Impact Toughness ◽  
Treatment Technique ◽  
Offshore Structure ◽  
Treatment Techniques ◽  
Temperature Impact ◽  
Low Temperature Impact Toughness ◽  
The Impact ◽  
Quenching And Tempering

AbstractCircle quenching and tempering (CQ&T), intercritical quenching and tempering (IQ&T) and regular quenching and tempering (Q&T) were used to study the influence of heat treatment techniques on the low temperature impact toughness of steel EQ70 for offshore structure. The steels with 2.10 wt. % Ni (steel A) and 1.47 wt. % Ni (steel B) were chosen to analyze the effect of Ni content on the low temperature impact toughness of steel EQ70 for offshore structure. The fracture morphologies were examined by using a scanning electron microscope (SEM, JSM-6480LV), and microstructures etched by 4 vol. % nitric acid were observed on a type 9XB-PC optical microscope. The results show that the impact toughness of steel A is higher than that of steel B at the same test temperature and heat treatment technique. For steel B, the energy absorbed is, in descending order, CQ&T, Q&T and IQ&T, while for steel A, that is CQ&T, IQ&T and Q&T. The effects of heat treatment on the low temperature impact toughness are different for steels A and B, the absorbed energy changes more obviously for steel A. The results can be significant references for actual heat treatment techniques in steel plant.

Effect of Different Heat Treatments on Microstructure and Mechanical Properties of the Martensitic Gx12CrMoVNbN9-1 Cast Steel / Wpływ Parametrów Obróbki Cieplnej Na Mikrostrukture I Własciwosci Mechaniczne Martenzytycznego Staliwa Gx12CrMoVNbn9-1

2013 ◽  
Vol 58 (1) ◽  
pp. 25-30 ◽  
Author(s):  
G. Golanski ◽  
J. Słania
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Impact Energy ◽  
Cast Steel ◽  
Lath Martensite ◽  
High Strength ◽  
Strength Properties ◽  
Microstructure And Mechanical Properties ◽  
Quenching And Tempering ◽  
Very High

The paper presents a research on the influence of multistage heat treatment with the assumed parameters of temperature and time on the microstructure and mechanical properties of high-chromium martensitic GX12CrMoVNbN9-1 (GP91) cast steel. In the as-cast state GP91 cast steel was characterized by a microstructure of lath martensite with numerous precipitations of carbides of the M23C6, M3C and NbC type, with its properties higher than the required minimum. Hardening of the examined cast steel contributes to obtaining a microstructure of partly auto-tempered martensite of very high strength properties and impact strength KV on the level of 9-15 J. Quenching and tempering with subsequent stress relief annealing of GP91 cast steel contributed to obtaining the microstructure of high-tempered lath martensite with numerous precipitations of the M23C6 and MX type of diverse size. The microstructure of GP91 cast steel received after heat treatment was characterized by strength properties (yield strength, tensile strength) higher than the required minimum and a very high impact energy KV. It has been proved that GP91 cast steel subject to heat treatment No. 2 as a result of two-time heating above the Ac3 temperature is characterized by the highest impact energy.

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