Joining Technologies for Aluminium Castings—A Review

Abstract

Aluminium castings have been widely used in many industries, including automotive, aerospace, telecommunication, construction, consumer products, etc., due to their lightweight, good electric and thermal conductivity, and electromagnetic interference/radio frequency interference (EMI/RFI) shielding properties. The main applications of aluminium castings are in automotive industry. For lighweighting purposes, more and more aluminium castings are used in the automotive vehicle structures to reduce weight, improve fuel efficiency, and reduce greenhouse gas emissions. However, due to the features of cast aluminium, such as porosity, poor surface quality, a tendency toward hot cracking, and low ductility, joining these materials is problematic. In this paper, the joining technologies for aluminium castings and the related issues, mainly cracking and porosity, are reviewed. The current state-of-the-art of joining technologies is summarized, and areas for future research are recommended.

Studies on the Quality of Joints and Phenomena Therein for Welded Automotive Components Made of Aluminum Alloy—A Review

“…Al castings from various processes possess different gas content, surface finish, and mechanical properties, causing variations in joinability by fusion welding and mechanical joining [587].…”

“…The same grade of castings obtained from different casting processes can differ in their gas content and joinability. Castings made by high-quality high-pressure die casting (HPDC), squeeze casting, and semi-solid metal SSM casting possess a much lower gas content [587].…”

“…Due to outgassing, high heating and cooling rates, and complex weld fluid flow, laser welding is the most sensitive to gas content, and for this reason, Al castings for laser welding need very low gas content to avoid high porosity in the welded joints. Hybrid welding, with a combination of laser beam welding and TIG or MIG welding, can be beneficial to the welding of Al castings [587].…”

“…Electron-beam welding, using a multiple-process technique, or hybrid laser welding can configure the molten baths to facilitate degassing and limit inhomogeneous porosity in the joint area. With such processes, joints with low porosity can be achieved [587].…”

Corrosion Behavior of Homogenized and Extruded 1100 Aluminum Alloy in Acidic Salt Spray

“…The 1100 alloy is a pure aluminum alloy with high specific strength, high fracture toughness, excellent thermal conductivity, and strong chemical corrosion resistance and weathering resistance. It has become one of the most versatile, cost-effective, and attractive metal materials being widely used in different industrial fields [ 1 , 2 ]. With the advocacy for global energy conservation and emission reduction, research on the corrosion performance of designed aluminum parts has found that the corrosion rate of aluminum alloys under acidic condensation conditions is much lower than that of certain steel grades [ 3 ].…”