Study on microstructures and work hardening behavior of ferrite-martensite dual-phase steels with high-content martensite

In the present study, the effect of intercritical heat treatment temperature on the tensile properties and work hardening behavior of ferritic-martensitic dual-phase steel have been investigated utilizing tensile test, microhardness measurement and microscopic observation. Plain carbon steel sheet with a thickness of 2 mm was heat treated at 760, 780, 800, 820 and 840 °C intercritical temperatures. The results showed that martensite volume fraction (Vm) increases from 32 to 81%with increasing temperature from 760 to 840 °C. The mechanical properties of samples were examined by tensile and microhardness tests. The results revealed that yield strength was increased linearly with the increase in Vm, but the ultimate strength was increased up to 55% Vm and then decreased afterward. Analyzing the work hardening behavior in term of Hollomon equation showed that in samples with less than 55% Vm, the work hardening took place in one stage and the work hardening exponent increased with increasing Vm. More than one stage was observed in the work hardening behavior when Vm was increased. The results of microhardness test showed that microhardness of the martensite is decreased by increase in heat treatment temperature while the ferrite microhardness is nearly constant for all heat-treated samples.

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Work Hardening Behavior of Fe-0.1 C Dual Phase Steel

BHM Berg- und Hüttenmännische Monatshefte ◽

10.1007/s00501-011-0036-x ◽

2012 ◽

Vol 157 (1) ◽

pp. 44-47 ◽

Cited By ~ 1

Author(s):

Majid Pouranvari

Keyword(s):

Work Hardening ◽

Dual Phase Steel ◽

Dual Phase ◽

Work Hardening Behavior ◽

Hardening Behavior

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Work-Hardening Behavior of Cold Rolled Interstitial-Free Steel Sheet and Dual Phase High Strength Steel Sheets Subjected to Two-Stage, Coaxial and Non-Coaxial Tension/Compression

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.651-653.83 ◽

2015 ◽

Vol 651-653 ◽

pp. 83-88 ◽

Cited By ~ 3

Author(s):

Satoshi Shirakami ◽

Shigeru Yonemura ◽

Tohru Yoshida ◽

Noriyuki Suzuki ◽

Toshihiko Kuwabara

Keyword(s):

Work Hardening ◽

Steel Sheet ◽

High Strength ◽

Dual Phase ◽

Interstitial Free ◽

If Steel ◽

Two Stage ◽

Work Hardening Behavior ◽

Hardening Behavior ◽

Cold Rolled

In-plane tension/compression tests of a cold rolled interstitial-free (IF) steel and sheet a 980MPa dual phase high strength steel sheet (980DP) were carried out to investigate the work-hardening behavior under two-stage loading paths. The two-stage loading paths consist of the uniaxial tension/compression for the rolling direction (RD) followed by unloading and subsequent uniaxial tension/compression in the 0°, 45° and 90° directions from the first loading direction (0°-, 45°- and 90°-loading). The work hardening behavior in the second loading was different between the 980DP and the IF steel. It was found that the work hardening behaviors were significantly affected by the inner product of the strain rate mode tensors for the first and second loading and that the effect of the deformation mode (tension/compression) was small.

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