摘要
目前对于爆炸焊接金属界面成波机理的模型只能对波状界面形成的某些方面给予定量或定性的描述,而不能全面地解释其中的所有现象。在对钛钢过渡层爆炸焊接研究时,通过扫描电镜观测钛/铜爆炸焊接波状界面,发现在放大2000倍时,钛铜之间并没有波状界面存在,而是“钛滴”在铜中形成了一个个“孤岛”状结合界面。当两板结合后的相对位移较大时,就会将界面波的波峰部分拉断,脱离原位形成“孤岛”。对爆炸焊接的理论分析以及实验研究表明,Richtmyer-Meshkov失稳机理可以更好地解释爆炸焊接波状界面的形成过程。爆炸焊接过程中,在碰撞点附近,爆炸焊接界面会出现一薄层熔化区,界面附近的材料处于准流体状态。当高压弹-塑性应力波到达时,就会引起界面的扰动,前面应力波引起的扰动在后续一系列应力波的作用下会进一步发展,形成典型的Richtmyer-Meshkov界面失稳。因此,Richtmyer-Meshkov失稳、冻结,是形成我们所观察到的爆炸焊接中各种类型的波状界面原因。
At present,the model of the forming mechanism of the wavy metal interface during explosive welding can only give a quantitative or qualitative description of some aspects of the forming process,rather than fully explaining all the phenomena involved.In the study of explosive welding of the titanium-steel transition layer,the wavy interface was observed by scanning electron microscopy.When the scanning electron microscope was enlarged to 2000 times,the wavy interface turned out to be titanium drops forming island shape bonding interface in the copper.When the relative displacement of the two plates is large,the crest part of the interfacial wave will be pulled off and the"island"will be formed.The theoretical analysis and experimental study of explosive welding show that the Richtmyer-Meshkov instability mechanism can better explain the formation process of the wavy interface in explosive welding.In the process of explosive welding,near the collision point,a thin layer of melting zone will appear at the welding interface,and the material near the interface is in a quasi-fluid state.When the high pressure elastic-plastic stress wave arrives,the interface disturbance will be caused,and the disturbance caused by the previous stress wave will further develop under the action of a series of subsequent stress waves,forming a typical Richtmyer-Meshkov interface instability.Therefore,Richtmyer-Meshkov instability and freezing are responsible for the formation of various types of wavy interfaces observed in explosive welding.
作者
谢礼宏
段卫东
蒋培
XIE Li-hong;DUAN Wei-dong;JIANG Pei(Wuhan University of Science and Technology,Wuhan 430081,China;Blasting Technology Research Center of Wuhan University of Science and Technology,China Railway Guangzhou Engineering Bureau Group Co.,LTD.,Wuhan 430081,China)
出处
《爆破》
CSCD
北大核心
2023年第2期154-159,165,共7页
Blasting
