冲压用薄规格S550MC热轧汽车钢带开发

Development of S550MC Hot-rolled Automobile Strip for Stamping

本文介绍了采用Cr-Ti微合金化代替Nb-Ti微合金化开发出低成本的冲压用S550MC热轧钢带工艺设计思路和产品组织性能控制及该产品的应用。Cr-Ti微合金化的S550MC钢利用Ti化合物的第二相析出物实现了细晶强化和沉淀析出强化;并利用Cr提高钢的淬透性,推迟珠光体和贝氏体转变,细化了珠光体和贝氏体,降低了合金成本,降低了厚度≤2.0mm薄板带的轧制变形抗力,提高了轧制稳定性,拓展了轧机极限规格,并且研究了调整钢带卷取温度对钢的综合性能进行平衡控制。

This paper introduces the process design idea, microstructure and property control and application of S550 MC hot rolled steel strip for stamping with Cr-Ti microalloying in low cost instead of Nb-Ti microalloying. In Cr-Ti microalloyed S550 MC steel, the second phase of Ti compound precipitates are used to realize fine grain strengthening and precipitation strengthening;and using Cr to improve the hardenability of steel, delay the pearlite and bainite transformation, refine pearlite and bainite, reduce the cost of alloy, decrease rolling deformation resistance of the sheet of thickness 2.0 mm or less, improve the stability of rolling, expand the mill’s limit, and the balance control of the comprehensive properties of steel by adjusting the coiling temperature of steel strip is also studied.