摘要
在连续热镀锌线上研究了RTH带钢温度和光整延伸率对Ti-IF钢光整热镀锌板组织和性能的影响。试验表明,当RTH带钢温度在830℃以下时,成品铁素体晶粒度为10.0级,织构类型以{332}、{114}为主,随着带钢温度的进一步提高,热镀锌板的晶粒逐渐粗化,织构成为典型的{111}织构,且取向密度增加,r值随之提高,但当带钢温度在900℃以上时,织构又趋于无规则分布,r值显著降低;光整延伸率对Ti-IF钢光整热镀锌板力学性能的影响很大,随着光整延伸率的提高,屈服强度明显提高,n值明显降低,延伸率降低,抗拉强度变化较小,且光整延伸率对性能的影响与成品铁素体晶粒尺寸有关,成品晶粒越粗,光整延伸率的影响越大。因此对于Ti-IF钢光整热镀锌板而言,n、r值是一对矛盾体,在制订热镀锌工艺时,需根据使用条件的不同,对其n、r值进行综合考虑。
Effect of hot dip process on the microstructure and mechanical properties of Ti-IF steel skin-passed galvanized sheet are studied on a continuous hot dip galvanizing line. The results show that the ferrite grain has a size of No.10 when the sheet temperature in RTH is below 830 ℃ and then coarsens gradually as sheet temperature increasing. As a result, the annealing texture of hot dip galvanized sheet changes from mainly {332}and {114} , when the ferrite grain is fine, to the typical {111} as the grain growth, accompanying with the increase of intensity, therefore the r-value increases. However, the r-value will decrease dramatically as the result of randomly distribution of texture when the sheet temperature in RTH exceeds 900 ℃. Skin-passing reduction has evidently effect on the mechanical properties of final products of Ti-IF steel skin-passed galvanized sheet. As the skin-passing reduction increasing, the yield strength increases obviously, the n-value decreases markedly, and the elongation decreases, but the tensile strength almost remains unchanged. In addition, its effect depends on the ferrite grain size of the final products. The coarser the ferrite grain is, the bigger the effect becomes. Therefore, r-value and n-value are contradictory to each other for skin-passed hot-dip galvanized Ti-IF sheets, and they should be balanced during planning hot-dip processes according to the application demand of customers.
出处
《钢铁钒钛》
CAS
北大核心
2003年第4期14-19,共6页
Iron Steel Vanadium Titanium
