Corrosion in laser powder bed fusion AlSi10Mg alloy

Abstract

Aluminum alloy AlSi10Mg is a widely used engineering material that offers a very high strength-to-weight ratio and easy processing. It is common in the aerospace, medical, and automotive industries and has excellent machining and casting properties, as well as being easily made into fine powder. In recent years, it has become one of the most common light-weight materials for additive manufacturing (AM). Its chemical composition and stability in powder form make it particularly ideal for laser powder bed fusion (LPBF) applications. It is one of the few available aluminum alloys that can be reliably processed using AM. Numerous studies have been dedicated to mechanical properties and design strategies, but much less attention has been given to corrosion behavior. This article reviews the corrosion behavior and the correlation between the microstructure and corrosion for AlSi10Mg when fabricated using an LPBF process. Specific topics reviewed include corrosion performance, corrosion issues (pores, surface roughness, and residual stresses), and passive film formation mechanisms and compare these to conventionally-manufactured counterparts. In addition, this review discusses available methods for mitigating and avoiding corrosion in LPBF-processed AlSi10Mg parts, including relevant post-processing methods.