模拟汽车板的烘烤工艺，研究了预变形量、烘烤温度和烘烤时间等对含铌低硅T RIP钢板组织和性能的影响，探讨了T RIP钢的烘烤硬化机理。结果表明，当预变形量小于4％时，烘烤硬化值随预变形量增大而增加，预变形量大于4％时反而降低了烘烤硬化效应；当烘烤温度低于170℃时，随烘烤温度的上升，烘烤硬化值明显增加，当烘烤温度高于170℃时，烘烤温度对烘烤硬化值影响不大；当烘烤时间在20 m in以内时，随烘烤时间的延长，烘烤硬化值显著增加，烘烤时间超过20 m in时，烘烤硬化值随烘烤时间的延长反而有所降低。通过对TRIP钢的烘烤硬化机理分析，建立了烘烤硬化值变化模型：ΔYBH ＝ΔYγ＋ΔYb＋ΔYγc＋ΔYdp＋ΔYc ，其中沉淀析出碳氮化物数量和Cottrell气团数目变化引起的ΔY dp＋ΔYc对烘烤硬化值变化影响相对显著。
Bake-hardening behavior of low silicon TRIP steel with niobium
In order to simulate baking process of automobile steel sheet ,baking treatment experiments at different pre-strains ,temperatures and times were carried out on low silicon TRIP steel with Nb . T he variation of the microstructures and bake-hardening values of the experimental steel during bak-ing treatment was investigated ,and the bake-hardening mechanism of TRIP steel was discussed .A model of variation of the bake-hardening value was built as follows :ΔYBH = ΔYγ + ΔYb+ ΔYγc+ΔYdp+ ΔYc ,in which effects of ΔYdp and ΔYc on the variation of the bake-hardening value (ΔYBH) are relatively strong ,which are the yield strength variations caused by the amount of carbide precipi-tation and Cottrell atmosphere .
T RIP steel sheetbaking conditionmicrostructurebake-hardening
NETL
NSTL
万方数据
维普
