论文部分内容阅读
以Al含量分别为0.86%和1.5%的两种不采用Si合金化的冷轧TRIP钢为对象,研究Al含量和热处理工艺对其显微组织与力学性能的影响规律。结果表明,在两相区保温使铁素体与奥氏体体积分数相当后,在370～450℃的贝氏体区等温均得到包括铁素体、贝氏体、残留奥氏体和马氏体的多相组织。由于Al起到了有效的稳定奥氏体作用,含Al较高的1.5Al钢的残留奥氏体体积分数及其碳含量均高于0.86Al钢。力学性能试验结果表明,1.5Al钢的最佳性能是屈服与抗拉强度分别为452MPa和756MPa,伸长率达到34%,对应的热处理工艺是850℃×300s快冷到400℃等温180s。而0.86Al钢在最佳工艺(800℃×300s后370℃等温180s)下的强度与伸长率均明显低于1.5Al钢,屈服与抗拉强度分别为413MPa和708MPa,伸长率仅为27%。
Two kinds of cold-rolled TRIP steels not containing Si alloyed with Al contents of 0.86% and 1.5%, respectively, were used to study the effect of Al content and heat treatment on the microstructure and mechanical properties. The results show that in the two-phase zone, the volume fraction of ferrite and austenite is the same, the ferrite, bainite, retained austenite and martensite are obtained in the isothermal bainite region at 370-450 ℃ Multi-phase body of the body. Since Al has an effective and stable austenite effect, the retained austenite volume fraction and carbon content of 1.5Al steel with higher Al are higher than that of 0.86Al steel. Mechanical properties of the test results show that the best performance 1.5Al steel yield and tensile strength were 452MPa and 756MPa, elongation of 34%, the corresponding heat treatment process is 850 ℃ × 300s rapid cooling to 400 ℃ isothermal 180s. However, the strength and elongation of 0.86Al steel were significantly lower than those of 1.5Al steel under the optimum conditions (temperature of 370 ℃ and 800 ℃ for 300s), yield and tensile strength were 413MPa and 708MPa respectively, and the elongation was only 27%.