Effects of Heat Treatment and Si Addition on the Mechanical Properties of 0.1 wt% C TRIP-aided Cold-rolled Steels.

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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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 mechanical properties of heavily cold-rolled Fe-6.5wt%Si alloy sheet

Science China Technological Sciences ◽

10.1007/s11431-010-0125-1 ◽

2010 ◽

Vol 53 (4) ◽

pp. 1008-1011 ◽

Cited By ~ 16

Author(s):

YongFeng Liang ◽

Feng Ye ◽

JunPin Lin ◽

YanLi Wang ◽

LaiQi Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Alloy Sheet ◽

Cold Rolled

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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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Tailoring the Mechanical Properties of Al-Sn-Alloys for Tribological Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.317 ◽

2007 ◽

Vol 539-543 ◽

pp. 317-322 ◽

Cited By ~ 9

Author(s):

Rafael Schouwenaars ◽

J.A. Torres ◽

Víctor H. Jacobo ◽

Armando Ortiz

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Surface Tension ◽

Low Temperatures ◽

Phase Distribution ◽

Cu Alloy ◽

Heat Treated ◽

Cold Rolled ◽

Physical Phenomena

A 95% cold-rolled Al-20%Sn-1%Cu alloy was heat-treated in a range of temperatures and times to investigate the evolution of mechanical properties and microstructure. The most interesting combination of properties can be achieved between 300 and 400°C in a process that is simpler than what is used in industry. The physical phenomena which are active during the heat treatment are precipitation, recovery, recrystallisation and change in phase distribution due to surface tension. The former two predominate at low temperatures, while the latter achieve faster kinetics at higher temperatures, where recrystallisation is coupled to the change in morphology of the contiguous Sn-phase.

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