Investigation of low-velocity impact and flexural loading on AR500 steel/AA7075 aluminum alloy brazed joint

Abstract

This paper presents the results of an experimental study to evaluate the damage and failure mode of AR500 steel/AA7075 aluminum alloy brazed joint panels caused by an impact load. Drop weight tests were conducted on AR500 steel/AA7075 aluminum alloy brazing joint panels to study their response and performance under impact loading. The use of steel and aluminum joints is becoming increasingly popular since they are well known for excellent weight, strength, and stiffness properties and this condition makes them the material of choice for lightweight applications in the automotive industry. In this work, AR500 steel/AA7075 aluminum alloy plates were fabricated by the torch brazing method with Al-Si-Zn base as the filler metal and evaluated for their impact performance and flexural strength by conducting drop weight tests under low velocity impacts and a three point bend test. Experimental results showed that the AR500 steel/AA7075 aluminum alloy brazed joint panel flexural strength was 615 N and the low velocity impact strength was 1569 N. The experiment caused delamination of the joint at the aluminum and filler metal region. The Al-Si-Zn filler bonding capability on the AA7075 aluminum was low compared to the AR500 steel. However, it is capable of joining these dissimilar metals. The data obtained from this study should assist researchers and designers to better understand damage and failure behaviour of panels made of dissimilar metals which will result in components with a better design. This is particularly so in the aspect of the crashworthiness properties of structural components, especially in static, quasi-static, and dynamic loadings.

Keywords

• brazing
• metal joining
• impact strength
• dissimilar metals