Microstructural and mechanical aspects of laser metal deposited H13 powder for die repair

Author(s)

Braga, V ^{[1, 2]} ; Siqueira, R. H. M. ^[2] ; Atilio, I ^{[1, 2]} ; Mansur, R. ^{[1, 2]} ; Vieira, D. ^{[1, 2]} ; Chen, D. L. ^[3] ; Lima, M. S. F. ^{[1, 2]}

Affiliation

^[1] Technol Inst Aeronaut, BR-12228900 Sao Jose Dos Campos, SP - Brazil

^[2] Inst Adv Studies, BR-12228001 Sao Jose Dos Campos, SP - Brazil

^[3] Ryerson Univ, Dept Mech & Ind Engn, Toronto, ON M5B 2K3 - Canada

• Document type: Journal article
• Source: MATERIALS TODAY COMMUNICATIONS; v. 29, DEC 2021.
• Web of Science Citations: 0

Abstract

In this study, the microstructural and mechanical properties of H13 powder deposited via laser metal deposition (LMD) on H13 hot work tool steel substrates were examined. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and electron backscatter diffraction (EBSD) were used to analyze the grain distribution, layer development, and carbide incidence. The mechanical properties were evaluated using Vickers hardness indentations. An alpha-ferrite matrix consisting of alpha'-martensite was identified along with a crack-free interface containing Mo-and Cr-rich precipitates between the additive-deposited H13 steel and the substrate. The EBSD results showed a highly consistent combination between the deposition and the substrate, along with a structure consisting of columnar and equiaxial grains resulting from the directional solidification process. Wear resistance tests demonstrated that the H13-deposited region was in a better condition than the substrate was due to the presence of martensite and carbides in the matrix. Finally, the average hardness levels of the substrate and deposition regions were determined to be 213 HV (alpha-Fe) and 671 HV (alpha'), respectively. The smooth transition in terms of hardness between the regions also indicated a tendency for lower stress concentrations. (AU)

• FAPESP's process: 19/25229-7 - The fabrication of small satellites with use of lasers
• Grantee: Rafael Humberto Mota de Siqueira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 16/11309-0 - The study, development and application of a hybrid process: Additive Manufacturing (AM) plus High Speed Machining/Grinding (HSM/G)
• Grantee: Reginaldo Teixeira Coelho
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/23884-5 - Evaluation of the additive manufacturing process in the microstructural and mechanical performance of repairs for injection molds
• Grantee: Vágner Braga
• Support Opportunities: Scholarships in Brazil - Doctorate