Brazed Joint Interface Bonding Strength of AR500 Steel and AA7075 Aluminium Alloy

Mohd Muhamed,Zainuddin Sajuri,Mohd Omar,Mohd Abdullah,Shahrum Abdullah,Wan Wan Zamri

doi:10.3390/met8090668

Mohd Muhamed, Zainuddin Sajuri + Show 4 more

Open Access

https://doi.org/10.3390/met8090668

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Abstract

The joining of aluminium alloys to steels has been extensively studied, especially in the automotive sector. However, aluminium alloys are known to be difficult to join with steels when methods involving fusion welding are used because of the hot cracking problem. Hence, a high-strength joint between these dissimilar metals would be of benefit especially in reducing the weight of products. In this work, the torch-brazing method was applied to join AR500 steel with AA7075 aluminium alloy using Al–Si–Zn base filler metal at various flame times. The effects of the brazing work on the intermetallic phase formation and the mechanical strength of the joints were investigated. In this work, the maximum shear load obtained was 6460 N and the presence of the intermetallic phases had reduced the shear strength of the brazed joints. However, the torch-brazing process using Al–Si–Zn filler metal had successfully facilitated the joining of these dissimilar metals.

Highlights

A joint between dissimilar metals provides many advantages, especially in terms of a reduction in the weight and cost of a product
Previous work had shown that the thickness of the intermetallic compound (IMC) layer increases with the increase in the
A previous work had shown that the thickness of the IMC layer increases with the increase brazing time and temperature [33]

Summary

Introduction

A joint between dissimilar metals provides many advantages, especially in terms of a reduction in the weight and cost of a product. The process of dissimilar metal joining is in great demand in many industries, such as the automotive, aviation, and aerospace industries. Studies on the joining of aluminium alloys and steels were first conducted many years ago because of the huge potential benefits, especially for the automotive industry, due to the possibility of reducing the weight of vehicle components and structures. There has been considerable research on the dissimilar metal joining of aluminium alloys and steel using several joining techniques, such as spot welding [8], laser welding [9], brazing [10,11,12], and friction stir welding [13]. A common problem encountered in many approaches is the formation of brittle aluminium-rich Al–Fe intermetallic compound (IMC) layers at Metals 2018, 8, 668; doi:10.3390/met8090668 www.mdpi.com/journal/metals

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