What aluminum alloys are commonly used in SLM, and what benefits do they offer?

AlSi10Mg – The Most Widely Used SLM Aluminum Alloy

AlSi10Mg is the dominant alloy used in SLM because it offers excellent printability, low cracking tendency, and a fine microstructure formed by rapid solidification. The silicon content improves fluidity and reduces thermal stresses, resulting in highly accurate, stable parts. AlSi10Mg provides an excellent strength-to-weight ratio, good thermal conductivity, and corrosion resistance, making it ideal for aerospace brackets, automotive housings, heat exchangers, and lightweight structural components.

Aluminum-Magnesium Alloys (AlMg)

Magnesium-containing aluminum alloys offer increased ductility and toughness. These alloys are especially valuable for components requiring energy absorption, impact resistance, or improved fatigue life. While they may require more precise laser energy control during SLM, they yield lighter and more flexible parts compared with silicon-rich alloys. They are often used in automotive and consumer-product applications where durability and weight reduction are priorities.

High-Strength Aluminum Alloys Under Development

Advanced high-strength alloys such as Sc- or Zr-modified aluminum (AlSi10Mg + Sc/Zr) are being increasingly adopted in SLM due to their ability to produce ultra-fine, stable grain structures. These modifications suppress hot cracking and improve strength, fatigue performance, and thermal stability. Such high-strength printed alloys are promising for demanding applications in power generation and advanced aerospace hardware.

Benefits of SLM-Specific Aluminum Alloys

Compared with cast or wrought aluminum, SLM-optimized alloys benefit from rapid solidification that increases hardness, strength, and dimensional accuracy. Alloys like AlSi10Mg develop fine microstructures that enhance mechanical properties, while maintaining low weight and corrosion resistance. Their compatibility with heat treatments—such as artificial aging—allows engineers to fine-tune mechanical performance for structural and thermal applications. These alloys also support the creation of complex geometries and integrated functional features not achievable through traditional processes.