Joining of light materials with highly corrosion-resistant metal by shot lining

Abstract

Magnesium and aluminum alloys are widely used in various industries owing to several attractive properties such as low density, high strength to weight ratio and reusability. However, magnesium alloys and high-strength aluminum alloys have undesirable properties including poor corrosion resistance and wear resistance. Therefore, surface modification is necessary to improve such properties of those alloys. In the present study, the high-corrosion resistance foil was joined to the surface of alloys using shot peening. The base materials were a commercially available magnesium alloy and aluminum alloy, and the high-corrosion resistance foils were pure aluminum, pure titanium, pure copper, pure nickel, pure iron and austenite stainless steel. The thickness of foils range from 0.02 to 0.06 mm. Shot peening was performed with a centrifuge equipment. The shots had an average diameter of 1.0 mm and were made of cast steel. The peening velocity was 60 m/s, and the peening time was 10 s. The processing temperature was 300 and 350 ℃ to facilitate plastic deformation. No voids and cracks were observed at the bonding interface. In bending test, the metal foil did not peel off even when the substrate was broken, and the metal foil was tightly bonded.