热轧不锈钢复合板界面组织与抗剪性能研究

Study on Shear Properties and Interfacial Microstructure of Hot-Rolled Stainless Steel Clad Plates

主要研究热轧不锈钢复合板界面组织特征与抗剪性能之间的关系,重点分析剪切试验界面断裂过程特征与抗剪结果的可信性。利用金相、SEM,EDS,TEM等手段观察结合界面微观组织,并严格按照国标进行显微硬度与剪切试验。通过分析发现,复合界面存在元素扩散,且不同元素的扩散距离不同,并导致在结合界面处形成带状组织的特殊形貌;结合界面处加入Ni箔后对界面元素扩散有一定的抑制作用,有利于改善界面不锈钢侧综合性能;剪切断口沿界面薄弱位置发生曲折开裂,参照界面元素扩散,可有效评定抗剪结果的准确性与可信性。

The present work aimed at studying the interfacial microstructure and shear properties of lowcarbon steel/stainless steel clad plates fabricated by hot-roll bonding. It is very interesting to evaluate the correlation between interfacial microstructure and shear properties, especially, the interfacial fracture behavior and the credibility of shear strength results. OM, SEM, EDS and TEM were used to observe the microstructure of the interface,and the microhardness and shear tests were carried out in strict accordance with the national standard. It was found that there was a diffusion phenomenon of chemical elements with different diffusion length around the interface and resulted in the special appearance of zonal structures. With the addition of Ni foil at the interface, the diffusion of the interface elements is inhibited, which is beneficial to improve the performance of stainless steel. Shear fracture occured zigzag cracks along the weak interface, and the accuracy and reliability of the shear results can be effectively evaluated by referring to the diffusion of interface elements.