摘要
通过比较含N i量(质量分数)分别为1.92%和4.92%的中碳Cr-N i-Mo系超高强度钢不同回火温度下的力学性能,得到了残留奥氏体分解及其对试验钢力学性能影响的规律。结果表明,200℃回火后两种试验钢的强度、伸长率和-40℃冲击吸收功分别>2200 MPa、>10%和>10 J。4.92%N i钢的屈服强度低,在拉伸过程中残留奥氏体应变诱导马氏体相变和相变诱发塑性(TR IP),伸长率有明显提高。随着回火温度的升高,残留奥氏体分解,4.92%N i钢的屈强比升高,应变硬化指数和伸长率均下降。
Tensile properties of the two medium carbon Cr-Ni-Mo steels with 1.92 wt% and 4. 92 wt% Ni respectively tempered at different temperatures were researched and compared. Effect of retained austenite on mechanical properties of the steels and the decomposition of retained austenite at different tempering temperatures were investigated. The results show that the two tested steels tempered at 200 ℃ exhibit that the tensile strengths , tensile elongations and Charpy V- notch impact toughness ＇at - 40℃ are more than 2200 MPa, 10% and 10 J respectively. The strain-induced transformation of retained austenite into martensite and transformation induced plasticity （TRIP） take place in tensile tests of 4. 92wt% Ni steel after quenching and low temperature tempering, and the elongation is increased resulting from these effects. With increasing the tempering temperature, volume fraction of retained austenite in 4. 92wt% Ni steel decreases, the yield ratio of 4. 92wt% Ni steel increases, and the elongation and strain hardening exponent decrease.
出处
《金属热处理》
EI
CAS
CSCD
北大核心
2007年第2期16-19,共4页
Heat Treatment of Metals
关键词
超高强度钢
残留奥氏体
相变诱发塑性
ultra-high strength steel
retained austenite
transformation induced plasticity （TRIP）
