Development of hot rolled DP590Y steel with excellent hole expandability for wheel disk
A two step cooling process (first water cooling,subsequent air cooling and second water cooling)on the run-out table (ROT)associated with suitable low temperature coiling is applied to produce hot rolled DP590Y steel.Because of the high difficulties to control step cooling and low coiling temperature (CT)for hot strip mill,not only the cooling process is concerned,the up-stream parameters such as chemical composition,slab reheating temperature,roughing mill exit temperature,finishing entry temperature,and finishing exit temperature (FXT)should be controlled precisely to achieve required mechanical properties.By adopting optimized hot rolling processes,the target mechanical properties of DP590Y are successfully achieved.In addition to the characteristic phases of ferdte and martensite,a third phase,tempered martensite,obtained by using slightly higher FXT and CT,is beneficial to the hole expandability of typical ferrite-martensite dual phase steels.
dual phase step cooling wheel disk tempered martensite hole expandability
Ming-Feng Lee Yeong-Tsuen Pan
Quality Assurance Section-Hot Rolled,Metallurgical Dept.,China Steel Corporation,Kaohsiung 81233,Tai Steel Products Development Section,Steel and Aluminum R & D Dept.,China Steel Corporation,Kaohsiung
国际会议
上海
英文
351-354
2008-09-26（万方平台首次上网日期，不代表论文的发表时间）