Selective Laser Melted M300 Maraging Steel-Material Behaviour during Ballistic Testing

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Growing interest in metal additive manufacturing (AM) for military applications, particularly for armor production.
• AM materials exhibit distinct properties compared to conventionally manufactured ones, especially under dynamic loading like ballistic impacts.
• M300 maraging steel is a candidate material for advanced armor solutions.

Purpose of the Study:

• To analyze the ballistic performance of M300 maraging steel produced via additive manufacturing.
• To evaluate the influence of solution annealing and ageing heat treatments on the material's behavior under ballistic testing.
• To investigate the structural and mechanical properties, including fracture analysis, of treated and untreated AM M300 maraging steel.

Main Methods:

• Ballistic testing of M300 maraging steel samples in as-built, solution annealed, and aged conditions.
• Structural analysis using microscopy.
• Tensile testing complemented by digital image correlation (DIC) for deformation analysis.
• Fracture surface examination to understand failure mechanisms.

Main Results:

• Solution annealing and ageing heat treatments improved ballistic properties by 87% compared to as-built samples.
• Heat-treated M300 maraging steel exhibited increased brittleness, leading to greater fragmentation upon perforation.
• Tensile testing and DIC revealed distinct deformation behaviors influenced by the processing and heat treatments.

Conclusions:

• M300 maraging steel, when subjected to pre- or post-processing heat treatments, is a viable material for certain armor applications.
• Optimizing heat treatment is crucial for balancing enhanced ballistic resistance with acceptable levels of brittleness and fragmentation.
• Further research into fracture mechanisms and material optimization is warranted for advanced AM armor development.