铝—铝爆炸焊接界面形貌特征研究

Morphology Characteristics of Al-Al Explosive Welding Interface

摘要:

基于爆炸焊接波状界面形成的失稳机理与流体—弹塑性模型，在飞板反向射流与空气之间存在着Rayleigh-Taylor、Kelvin-Helmholtz不稳定性条件，因而提出失稳是发生在金属流体薄膜与空气之间。由界面波幅与波长之比判定线性理论成立，从而建立双层流体失稳线性控制方程，获得失稳发展特征指数表达式。结果表明在金属流体弹—粘性与失稳机制竞争作用下，特定波长范围的扰动能够被优先发展，其他波长的扰动被抑制或未能发展，从而使得波状界面在沿爆轰方向较为一致，实验结果也验证了这一结论的正确性

Abstract:

Based on the instability mechanism of wave formation at the interface in explosive welding and fluid-elastic-plastic model, the conditions for Rayleigh-Taylor and Kelvin-Helmholtz instability were found between fly plate back and air. Therefore, the instability between metal fluid foil and air was proposed. It can be deduced from the ratio of amplitude and wavelength that linear relationship is proper. Then we established double layer fluid flow instability linear control equations, and gained expression of instability development exponent. Results show that at the competition between metal fluid elastic-viscosity and Helmholtz-Taylor synthesized instability, disturbances of special wavelength are prior developed, while others are attenuation or have no time to develop. Consequently, the wavelength and amplitude of welding interface along detonation direction is uniform. In addition, experiments also validate this conclusion