热处理工艺对低碳Si-Mn系TRIP钢组织和性能的影响

Influences of Heat Treatment on Microstructure and Mechanical Properties of Low Carbon Si-Mn TRIP Steel

采用定量彩色金相、X射线衍射和拉伸试验等方法,研究了热处理工艺及不同的冷轧压下率对低碳Si-Mn系TRIP钢组织和力学性能的影响。结果表明,对于不同的退火温度,再结晶铁素体和二次铁素体的含量不同。当冷轧压下率为55%时,经820℃×110 s+410℃×440 s热模拟工艺后,实验钢中铁素体量约为60%,贝氏体和马氏体量约为34%,残余奥氏体含量约为6%,残余奥氏体的碳含量为1.3%,可以获得好的相变诱发塑性及好的强韧性配合。

The influences of heat treatment and cold rolling reduction rate on the microstructure and mechanical properties of low carbon Si-Mn TRIP steel were studied by color metallograph method,X-ray diffraction and tensile testing.The results show that for different intercritical annealing temperatures,the volume fraction of αRex and αⅡ is different.The volume fraction of ferrite is 60%,the volume fraction of bainite and mastensite is 34%,and the volume fraction and carbon content of retained austenite reachs the highest values of 6% and 1.3%,respectively.The best product in strength and ductility is obtained by heat-treating in 820 ℃× 110 s ＋ 410 ℃ × 440 s when cold rolling reduction rate is 55%.