Effect of heat treatment on mechanical properties of heavily cold-rolled Fe-6.5wt%Si alloy sheet

The effect of austenitizing temperature and aging treatment on the microstructure and mechanical properties of two new cold-rolled automotive steel plates (20Mn2Cr and 20Mn2CrNb) was investigated by using isothermal heat treatment, optical microscope, scanning electron microscope, microhardness tester, and tensile testing machine. The results show that as the austenitizing temperature increased, the original austenite grain sizes of both steels increased. The original austenite grain size of 20Mn2CrNb was smaller than that of 20Mn2Cr. The microhardness of 20Mn2CrNb gradually decreased with increasing aging temperature, while the hardness of 20Mn2Cr varied irregularly. The mechanical properties of 20Mn2Cr were better than those of 20Mn2CrNb under the same heat-treatment process. The effect of heat treatment on microstructure and mechanical properties was related to the martensite content, dislocation density, and precipitation of second-phase particles.

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Effects of Post Heat Treatment on the Mechanical Properties of Cold-Rolled Ti/Cu Clad Sheet

Metals ◽

10.3390/met10121672 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1672

Author(s):

Chang-Suk Youn ◽

Dong-Geun Lee

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Rolling Process ◽

Post Treatment ◽

Post Heat Treatment ◽

Clad Sheet ◽

Heat Treated ◽

Bonding Properties ◽

High Elongation ◽

Cold Rolled

Titanium and titanium alloys have excellent corrosion and heat resistance, but weak electric and thermal conductivity. The weak conductivity of titanium can be overcome by cladding with copper, which has high conductivity. Although titanium is expensive, it is selected as a material suitable for applications requiring corrosion resistance such as in heat exchangers. This study was to investigate the effect of post heat treatment on the mechanical properties of the Ti/Cu cold-rolled clad plate by using the interfacial diffusion bonding. A titanium clad by cold rolling should be heat-treated after the rolling process to improve the bonding properties through the diffusion of metals and removal of residual stress due to work hardening, despite the easy formation of intermetallic compounds of Ti and Cu. As a result post-treatment, the elongation was improved by more than two times from 21% to max. 53% by the Ti-Cu interface diffusion phenomenon and the average tensile strength of the 450 °C heat-treated specimens was 353 MPa. By securing high elongation while maintaining excellent tensile and yield strength through post-treatment, the formability of Ti-Cu clad plate can be greatly improved.

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Mechanical Properties of Cold-Rolled and Annealed Al–12%Mg Alloy Sheet with High Mg Solid Solubility Fabricated from Vertical-Type High-Speed Twin-Roll Cast Strip

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.f-m2019850 ◽

2019 ◽

Vol 60 (11) ◽

pp. 2435-2441 ◽

Cited By ~ 2

Author(s):

Yohei Harada ◽

Nan Jiang ◽

Shinji Kumai

Keyword(s):

Mechanical Properties ◽

Solid Solubility ◽

High Speed ◽

Alloy Sheet ◽

Mg Alloy ◽

Cast Strip ◽

Cold Rolled ◽

Twin Roll Cast ◽

Twin Roll

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Influence of Microstructural Morphology on Hydrogen Embrittlement in a Medium-Mn Steel Fe-12Mn-3Al-0.05C

Metals ◽

10.3390/met9090929 ◽

2019 ◽

Vol 9 (9) ◽

pp. 929 ◽

Cited By ~ 2

Author(s):

Xiao Shen ◽

Wenwen Song ◽

Simon Sevsek ◽

Yan Ma ◽

Claas Hüter ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

The Other ◽

Duplex Microstructure ◽

Ultrafine Grained ◽

Medium Mn Steel ◽

Microstructural Morphology ◽

Cold Rolled ◽

Mixed Microstructure ◽

Mn Steel

The ultrafine-grained (UFG) duplex microstructure of medium-Mn steel consists of a considerable amount of austenite and ferrite/martensite, achieving an extraordinary balance of mechanical properties and alloying cost. In the present work, two heat treatment routes were performed on a cold-rolled medium-Mn steel Fe-12Mn-3Al-0.05C (wt.%) to achieve comparable mechanical properties with different microstructural morphologies. One heat treatment was merely austenite-reverted-transformation (ART) annealing and the other one was a successive combination of austenitization (AUS) and ART annealing. The distinct responses to hydrogen ingression were characterized and discussed. The UFG martensite colonies produced by the AUS + ART process were found to be detrimental to ductility regardless of the amount of hydrogen, which is likely attributed to the reduced lattice bonding strength according to the H-enhanced decohesion (HEDE) mechanism. With an increase in the hydrogen amount, the mixed microstructure (granular + lamellar) in the ART specimen revealed a clear embrittlement transition with the possible contribution of HEDE and H-enhanced localized plasticity (HELP) mechanisms.

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Effect of Heat Treatment on Microstructure and Mechanical Properties in ZK60 Alloy Sheet

Materials Science Forum ◽

10.4028/www.scientific.net/msf.567-568.361 ◽

2007 ◽

Vol 567-568 ◽

pp. 361-364 ◽

Cited By ~ 8

Author(s):

Suk Bong Kang ◽

Jae Hyung Cho ◽

Hyoung Wook Kim ◽

Y.M Jin

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Solution Treatment ◽

Aging Treatment ◽

Growth Direction ◽

Warm Rolling ◽

Alloy Sheet ◽

Microstructure And Mechanical Properties ◽

Zk60 Alloy ◽

Hardness Values

The sheet of ZK60 alloy with a thickness of 1mm was prepared from a casting ingot followed by homogenization and warm-rolling. Variations in microstructure and mechanical properties of ZK60 alloy sheets were investigated during T6 treatment. Especially artificial aging after solution heat treatment affected both precipitates distribution and mechanical properties with aging treatment. Variations of mechanical properties were related to precipitates, i.e. rod-shaped ( 1 β ′ ) or disc shaped ( 2 β ′ ) particles. Around the peak of hardness values, regularly distributed rod-shaped ( 1 β ′ ) precipitates were found. The rod-shaped ( 1 β ′ ) precipitates were oriented with a growth direction of [0001]. When over-aged, rod-shaped ( 1 β ′ ) precipitates were expected to decrease and the density of disc-shaped ( 2 β ′ ) precipitates to change. The rod-shaped ( 1 β ′ ) precipitates mainly consist of {Mg, Zn}, while disc-shaped ( 2 β ′ ) precipitates, {Mg, Zn, Zr} or {Mg, Zn}. In this study the optimum T6 treatment was determined as solution treatment at 430 °C for 6 hours and subsequently aging treatment at 175 °C for 18 hours. At this T6 condition the tensile strength, yield strength and elongation are 321MPa, 280MPa and 16%, respectively.

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Grain Refinement and Improved Mechanical Properties of EUROFER97 by Thermo-Mechanical Treatments

Applied Sciences ◽

10.3390/app112210598 ◽

2021 ◽

Vol 11 (22) ◽

pp. 10598

Author(s):

Giulia Stornelli ◽

Andrea Di Schino ◽

Silvia Mancini ◽

Roberto Montanari ◽

Claudio Testani ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Heat Treatments ◽

Treatment Temperature ◽

Steel Plates ◽

Experimental Campaign ◽

Different Temperatures ◽

Fusion Applications ◽

Cold Rolled

EUROFER97 steel plates for nuclear fusion applications are usually manufactured by hot rolling and subsequent heat treatments: (1) austenitization at 980 °C for 30 min, (2) rapid cooling and (3) tempering at 760 °C for 90 min. An extended experimental campaign was carried out with the scope of improving the strength of the steel without a loss of ductility. Forty groups of samples were prepared by combining cold rolling with five cold reduction ratios (20, 40, 50, 60 and 80%) and heat treatments at eight different temperatures in the range 400–750 °C (steps of 50 °C). This work reports preliminary results regarding the microstructure and mechanical properties of all the cold-rolled samples and the effects of heat treatments on the samples deformed with the greater CR ratio (80%). The strength of deformed samples decreased as heat treatment temperature increased and the change was more pronounced in the samples cold-rolled with greater CR ratios. After heat treatments at temperature up to 600 °C yield stress (YS) and ultimate tensile strength (UTS) of samples deformed with CR ratio of 80% were significantly larger than those of standard EUROFER97 but ductility was lower. On the contrary, the treatment at 650 °C produced a fully recrystallized structure with sub-micrometric grains which guarantees higher strength and comparable ductility. The work demonstrated that EUROFER97 steel can be strengthened without compromising its ductility; the most effective process parameters will be identified by completing the analyses on all the prepared samples.

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TEXTURE AND FORMABILITY DEVELOPMENT OF ASYMMETRY ROLLED AA 3003 AL ALLOY SHEET

International Journal of Modern Physics B ◽

10.1142/s0217979208051339 ◽

2008 ◽

Vol 22 (31n32) ◽

pp. 5895-5900 ◽

Cited By ~ 6

Author(s):

INSOO KIM ◽

SAIDMUROD AKRAMOV ◽

HAE BONG JEONG

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Plastic Strain ◽

Research Work ◽

Heat Treating ◽

Alloy Sheet ◽

Al Alloy ◽

Fine Grain ◽

Heat Treated ◽

Crystallographic Orientations

The physical, mechanical properties and formability of sheet metal depend on preferred crystallographic orientations (texture). In this research work, we investigated texture development and formability of AA 3003 aluminum alloy sheets after asymmetry rolling and subsequent heat treatment. After asymmetry rolling, the specimens showed fine grain size. We also investigated the change of the plastic strain ratios after asymmetry rolling and subsequent heat-treating condition. The plastic strain ratios of asymmetrically rolled and subsequent heat treated samples are 1.5 times higher than the initial AA 3003 Al alloy sheets. These could be attributed to the formation of ND//<111> texture component through asymmetry rolling in Al sheet.

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