气化冲击焊飞板碰撞速度测量及影响因素分析

Study on Impact Velocity of Flyer with different thickness Aluminum Foils

摘要:

气化冲击焊接技术可广泛用于难以焊接成形的钛、镁和铝等有色金属材料与钢材的连接。铝箔作为气化冲击焊接过程能量转换的载体，它的工作效率对气化冲击焊接工艺起到至关重要的作用。本文分析了气化冲击焊接过程中能量转换的过程，采用光子多普勒测速系统分析了三种不同厚度的铝箔在不同能量输入条件下铝箔的工作效率和对飞板与靶板碰撞速度的影响规律。当飞板与靶板间距（碰撞角度5 °）为2.5 mm时，铝箔的气化能量是影响飞板与靶板碰撞速度的关键因素。通过碰撞速度的分析可以发现，0.051 mm铝箔在输入能量小于3 kJ时效率最高，0.076 mm铝箔在3 kJ-6 kJ效率最高， 6 kJ-12 kJ时，0.127 mm的铝箔可以获得最佳效率。

Abstract:

Vaporizing Foil Actuator Welding (VFAW) has the promising potential to be widely used to join steel with non-ferrous metals, such as titanium, magnesium, and aluminum alloys, which is difficult with fusion welding techniques. The aluminum foil acts as the medium of energy transmission from electric energy to dynamic energy during VFAW process. Its working efficiency is of vital importance for the welding technique. In this article, the influence of the working efficiency of the aluminum foil on impact velocity between the flyer and target was explored via Photon Doppler Velocimetry (PDV) experiments. The experiments were carried out with foils of three different thicknesses under varied input energies. When the distance between the fly and target was 2.5mm with the impact angle of 5°, the vaporization energy of the foil is the key factor contributing to the impact velocity. According to the analysis of impact velocities, the 0.051mm –thick aluminum foil has the best efficiency with the input energy under 3 kJ, 0.076mm-thick aluminum foil works most efficiently with the input energy of 3kJ to 6kJ, and with the input energy of 6kJ to 12kJ, the 0.127mm-thick aluminum foil has the highest working efficiency.