真空轧制825合金/X65钢复合板的组织性能

Microstructure and mechanical property of vacuum hot-rolled 825 alloy/X65 pipeline steel clad plate

针对油气输送领域对耐H_2S腐蚀油气复合管线的需求,采用真空轧制复合技术成功制备出825镍基合金/X65高强管线钢复合板。真空轧制复合技术是基于真空电子束焊接和热轧复合所开发出的一种新型复合技术,在高真空、高温和强塑性变形条件下,复合界面实现优异的冶金结合。采用X65/825合金/825合金/X65的4层对称复合轧制模式,并对复合界面的微观组织和力学性能特征进行分析。研究表明,复合界面连续平直,无孔洞和裂纹等缺陷,镍、铬和铁元素在界面两侧发生明显的扩散,另外复合界面生成一条连续的厚度约为1μm的TiC薄带,在结合界面离散分布少量的颗粒状Al_2O_3化合物。界面平均剪切强度为404 MPa,拉剪断裂在复合界面处。

In order to ensure the requirement for H2S corrosion resistance pipeline in the oil and gas transportation fields,the 825 Ni-based alloy and X65 pipeline steel were combined successfully by vacuum rolling cladding（VRC）technique. The VRC is a new type cladding technique based on electron beam welding and hot rolling cladding. Under the condition of high vacuum level,elevated temperature and severe deformation,the excellent metallurgical bonding was performed on the clad interface. Four-layer symmetry rolling of X65-steel 825-steel 825-X65 was used and the microstructures and shear tension properties of the clad interfaces were investigated. The results indicated that the cladding interface was continuous and straight without any porosity and crack,and a thin continuous TiC layer with a small amount of Al2O3 particles was distributed on the interface. Besides,obvious inter-diffusions of Fe,Cr and Ni elements were detected at the interface. The average tension shear strength of the cladding interface reached 404 MPa,and the fracture located at the cladding interface.