不同应力状态下带钢的破鳞机理

利用自主设计的拉矫机对热轧带钢进行不同应力状态的破鳞试验,采用金相显微镜、扫描电镜和能谱分析对破鳞前后氧化皮的表面和界面进行分析,研究了带钢不同应力状态下的破鳞机理.试验结果表明,随着拉应力和压应力的增大,氧化皮全剥落率不断增大,并逐渐趋于稳定,且压应力的破鳞效果强于拉应力;拉应力作用下氧化皮以分层剥落为主,外层Fe3O4发生剥落,内层FeO仅在缺陷处发生少量剥落;而压应力作用下氧化皮以全剥落为主,临界弯曲应力随剥落量的增大而增大.

Spalling mechanisms of oxide scale of strip under different stress states

In order to study spalling mechanisms of oxide scale of strip under different stress states,hot rolled strip was descaled by self designed tension leveler.The surface and the interface of oxide scale were analyzed by metalloscope,SEM and EDS.The results show that complete spalling rate of oxide scale increases with the increase of tensile stress and compressive stress.The compressive stress has a larger effect than the tensile stress on the spalling of oxide scale.Oxide scale is mainly laminated spalling under tensile stress.The outer layer of Fe3O4 spalls,and the inner layer of FeO only has a small amount of spallation which just occurs at the defect site.Oxide scale is mainly complete spalling under compressive stress and the critical bending stress increases with the increase of the complete spalling rate.