The Effect of Heat Treatment on the Microstructure and Mechanical Properties of Multilayered Composites Welded by Explosion

The structure of composites formed by explosive welding of thin sheets of tool and austenitic steels was studied by structural analysis methods. It is shown that the quenching and tempering of composites leads to the formation of complicated structure containing, along with layers of dissimilar steels, layers with new chemical compositions. Due to the structural changes there is an 2-fold increasing of impact toughness.

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Hardness behavior of W. Nr. 1.7709 steel, oil quenched and tempered between 475°C and 575°C

MATEC Web of Conferences ◽

10.1051/matecconf/202134902005 ◽

2021 ◽

Vol 349 ◽

pp. 02005

Author(s):

John Mantzoukas ◽

Dimitris G. Papageorgiou ◽

Carmen Medrea ◽

Constantinos Stergiou

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Working Conditions ◽

Technical Information ◽

Chemical Compositions ◽

Treatment Sequence ◽

Tempering Temperature ◽

Different Temperatures ◽

Alloy Steels ◽

Quenching And Tempering

Steel components frequently involve a heat treatment to improve mechanical properties. In order to meet difficult working conditions, several components are hardened by quenching. W. Nr. 1.7709 is a representative structural steel with very low thermal conductivity among EN wrought alloy steels, which is extensively used after hardening and tempering. Although the steelmakers provide technical information about their heat treatment sequence, the tempering diagram of the specific grade has not been designed yet. The present paper analyses the temper resistance of the specific steel after oil quenching and tempering at high temperatures. Samples of identical chemical compositions were accordingly prepared and randomized. Five groups of ten specimens were austenitized at 960°C, hold for 30 minutes and were quenched in oil. They were tempered for two hours at different temperatures between 475°C and 575°C. Specific temperatures are interesting to the heat treaters, as they could allow certain transformations which take place during tempering. Hardness measurements were carried out and statistically processed. The tempering diagram was plotted to the specified temperature range. The influence of tempering temperature on steel hardness was analysed and the resistance to tempering back of the steel was discussed. The tempering diagram is critical for metallurgists as it represents a guide to define the proper tempering parameters so that the hardness predicted according to the mechanical property requirements are obtained.

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

THE IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING ◽

10.32852/iqjfmme.vol18.iss1.78 ◽

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.

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Permanent Mold Casting Practice and Microstructure and Mechanical Properties of Thin-Sectioned ADI Casting

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.26-28.531 ◽

2007 ◽

Vol 26-28 ◽

pp. 531-534

Author(s):

B.M. Moon ◽

Bong Hwan Kim ◽

Je Sik Shin ◽

Sang Mok Lee

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Ductile Cast Iron ◽

Treatment Temperature ◽

Chemical Compositions ◽

Permanent Mold ◽

Permanent Mold Casting ◽

Treatment Practice ◽

Mold Casting ◽

Si Content

For thin-walled casting development of austempered ductile iron (ADI), permanent mold casting and accompanied heat treatment practice were systematically investigated to suppress and/or remove chill defects of ductile cast iron (DCI) with various thickness of 2 to 9 mm and to ensure mechanical properties of the final ADI casting. Si content was increased up to 3.8% to reduce the chill formation tendency under a high cooling rate. The residual Mg content remarkably affected the nodule count, while the nodule size and spherodization were proven to have weak relationships. Austenitizing process followed by austempering was very sensitive to chemical compositions (Si and Sn) and heat treatment temperature. As a practical application, the steel bar coupler for a structural frame was tried to produce without subsequent machining.

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Influence of the energy electron beam exposure regimes on the structure and mechanical properties of composite coatings

Izvestiya vysshikh uchebnykh zavedenii. Fizika ◽

10.17223/00213411/63/11/23 ◽

2020 ◽

pp. 23-27

Author(s):

T.A. Krylova ◽

◽

Y.A. Chumakov ◽

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Wear Resistance ◽

Electron Beam ◽

Structural Changes ◽

Composite Coatings ◽

Initial State ◽

Austenitic Structure ◽

Solid Carbide ◽

Soft Ferrite

The effect of heat treatment on the structure and properties of composite coatings based on chromium carbide with titanium carbide fabricated by non-vacuum electron beam cladding without has been studied. It was shown that tempering leads to a decrease in microhardness and wear resistance, which is associated with the decomposition of the austenitic structure with the formation of a soft ferrite-carbide structure. The post heat treatment tempering was showed to decrease of microhardness and wear resistance, which leads to the decomposition of the austenitic structure with the formation of a soft ferrite-carbide structure. The bulk quenching of coatings after tempering leads to an increase in microhardness comparable to the values of microhardness in the initial state after electron beam cladding, due to the formation of high hard martensite. The wear resistance of composite coatings after tempering is lower than after cladding due to brittle martensite, which is not able to hold solid carbide particles. The composite coatings obtained at the optimal processing conditions have a combination of improved properties and do not require additional heat treatment, resulting in structural changes, causing a decrease in mechanical properties.

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

Metals ◽

10.3390/met9050575 ◽

2019 ◽

Vol 9 (5) ◽

pp. 575 ◽

Cited By ~ 8

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.

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

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.284.351 ◽

2018 ◽

Vol 284 ◽

pp. 351-356 ◽

Cited By ~ 1

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).

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Optimization for Heat Treatment Process of Supercritical Material F92Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.142.95 ◽

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.

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Effect of Grain Refinement on Mechanical Properties in 25Cr-1N Austenitic Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.3549 ◽

2010 ◽

Vol 638-642 ◽

pp. 3549-3554 ◽

Cited By ~ 1

Author(s):

Toshihiro Tsuchiyama ◽

T. Onomoto ◽

K. Tsuboi ◽

Setsuo Takaki

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Stress Concentration ◽

Grain Refinement ◽

Intergranular Fracture ◽

Tensile Deformation ◽

Austenitic Steels ◽

High Yield ◽

Structure Characteristic ◽

Step Heat Treatment

The Fe-25Cr-1N alloy produced by solution nitriding possesses extremely high yield strength owing to the solid solution strengthening by nitrogen. However, it was found that the steel exhibited an insufficient elongation because of the brittle intergranular fracture caused during the uniform tensile deformation. This is due to the marked stress concentration at grain boundaries, which is derived from the grain coarsening caused during long time solution nitriding and the development of planar dislocation structure characteristic of high nitrogen austenitic steels. The most effective way to reduce the stress concentration at grain boundary during deformation should be grain refinement. In this study, grain refinement was attempted by the two-step heat treatment for the Fe-25Cr-1N(-Mn) alloy, and then the mechanical properties were investigated by means of tensile tests and fatigue tests. The two-step heat treatment resulted in the grain refinement of austenite to 20 microns in diameter. The intergranular fracture was greatly suppressed from 70% (as-solution-nitrided) to 10% (grain-refined) in area fraction by the grain refinement. In addition, elongation was markedly increased with local necking. The yield stress and tensile strength were also increased, and thus, the fatigue limit is also raised by more than 30%.

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