Maraging 300 Steel Plasma Welding Characterization for Aerospace Application

Maraging steel is a special class of high-strength steels that are hardened by the precipitation of intermetallic compounds at temperatures close to 480 °C, without carbon transformation. Since its development, it has been used for strategic applications (nuclear energy, defense, and aerospace areas) and the mastery of its process and application has been constantly improved. This study aimed to characterize the weld regions of a maraging 300 steel used to manufacture a rocket motor case. Welded samples of maraging 300 steel were subjected to metallurgical and mechanical characterization. Microstructural analysis showed three different zones in the hardness range of 291 to 465 HV and reduced toughness. X-ray diffraction showed metallic phases in each region, evidencing the increase of the austenite phase. Based on the results obtained, maraging steel has great potential for aerospace applications, with excellent strength even when subjected to welding.

Keywords:
Maraging; plasma welding; aerospace application; rocket motor case