Effects of niobium on steels manufactured by additive manufacturing subjected to different fatigue mechanisms

• Grant number: 23/13192-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: November 01, 2023
• End date: October 31, 2027
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Kahl Dick Zilnyk
• Grantee: Rodrigo Vieira Garcia Barbosa
• Host Institution: Divisão de Engenharia Mecânica (IEM). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil
• Associated research grant: 20/06984-6 - Development of the additive manufacturing production chain of metal components, AP.NPOP

Abstract

The proposal fits into the study of advanced materials, with both automotive and aerospace applications, such as HSLA steel and 17-4PH stainless steel. One of the most present manufacturing technologies in these sectors today is the additive manufacturing of metallic alloys, becoming a very interesting target of studies, not only academic, but also marketing. Therefore, it is desired to study these steels with additions of niobium, manufactured by additive manufacturing, by the processes of LPBF (Laser Powder Bed Fusion) and DED (Directed Energy Deposition), under combinations of different routes of thermal, thermochemical and finishing treatments. superficial. As steels and alloys in general manufactured by these additive manufacturing processes have a certain amount of residual stress, it is interesting to study the effect of niobium on recrystallization during austenitization / solubilization treatments, in addition to obviously studying the formation of niobium carbides ( NbC) both to prevent the formation of chromium carbides (types M23C6 and M7C3 mainly), and to increase mechanical strength and anchorage of grains, and finally, to study the influence of niobium on the precipitation of intermetallic phases in these steels. Consolidating the study in the analysis of the mechanical properties, mainly in the life in flexor-rotary fatigue, axial, multiaxial and in bearing contact fatigue. (AU)