爆炸焊接304/Q245复合钢界面结构及剪切行为各向异性研究

Study of the Heterogeneity on Interface Structure and Shear Performance for the 304 Stainless Steel /Q245 Steel Explosive Welding Plate

摘要:

以304不锈钢 /Q245普碳钢焊接界面为研究对象,本文系统地探讨了界面结构不均匀性及其对服役行为的影响。研究过程中首先观察横截面、纵剖面结构的不均匀性,并基于非平衡运动方程,解释界面结构产生不均匀性的机理。进一步,针对界面波的方向特性,测试其剪切行为随定位角变化特征。最后利用SEM观察剪切断口形貌,认识界面结构对其断裂模式影响。研究表明,爆炸焊接装药爆轰压力脉动是导致界面结构不均匀性的根本原因,而界面波延展方向决定了断裂失效模式和损伤裂纹扩展行为；此外,本文获得了界面最优剪切强度承载方向,可指导爆炸复合材料应用于工程实践。

Abstract:

The 304 stainless steel/Q245 carbon steel explosive welding interface was taken as the research object to systematically detect the structure heterogeneity and its effect on the shear behavior in engineering application. First, characters on the transverse section and longitudinal section of the welding interface were detected. And based on the non-equilibrium theory, the mechanism of the heterogeneity on the welding interface has been explained. Furthermore, taking into account the wavy structure and its undulance along the detonation direction, shear performances varied with orientation angles were measured according to the national standard (GB/T 6396-2008). Finally, the morphologies of fracture surface were observed by SEM to recognize the influence of welding interface structure on the failure mode. Results show out that the explosive detonation pressure fluctuation is the fundamental cause of the inhomogeneity on the welding interface, the failure mode and cracks developments were determined by the undulation characters of wavy interface. Besides, an optimal orientation angle, on which samples have the maximum shear strength, was revealed. All of them can be used to guide the engineering application for explosive welding plates.