Impact of Heat Treatments on Residual Stress in Additively Manufactured AISI H13 Tool Steel

Autor(es)

Conde, Fabio Faria ; Fonseca, Eduardo B. ; Freire, Suyanny A. ; Lopes, Eder S. N.

• Tipo de documento: Artigo Científico
• Fonte: Journal of Materials Engineering and Performance; v. N/A, p. 11-pg., 2025-06-11.

Resumo

Additive manufacturing (AM), or 3D printing, enables the fabrication of complex and customized components directly from digital models. Despite its advantages, a major challenge is the generation of residual stresses due to the unique thermal cycles in AM processes. These stresses, caused by layer-by-layer material deposition with uneven heating and cooling, can affect the mechanical performance and reliability of parts-potentially leading to distortion, cracking, or failure. In this study, the formation and evaluation of residual stresses in AISI H13 tool steel processed by powder bed fusion with laser beam (PBF-LB) were investigated. The samples were manufactured using a Yb:YAG fiber laser with an 80 mu m spot size, 172 W power, and 700 mm/s scan speed. Post-processing included quenching followed by either single or double tempering, at temperatures of 650 degrees C and 550 degrees C. Thermodynamic simulations were performed to predict phase formation and physical properties, aiming to assess the impact of phase transformation on volumetric changes and, consequently, on residual stress development. Microstructural analysis and hardness tests were conducted, revealing that double-tempered samples at 550 degrees C exhibited the highest hardness, reaching 665 HV. A recently developed x-ray diffraction method was used to evaluate residual stresses by analyzing 2-theta peak shifts with a 2D detector, allowing for the estimation of lattice parameter changes. Residual stress results were correlated with microstructural features and hardness values. Compressive residual stresses were associated with the formation of fresh martensite from retained austenite and carbide precipitation. Additionally, hardness was strongly correlated with full width at half maximum (FWHM) variation, indicating microstructural refinement. This integrated approach provides valuable insights into the control and prediction of residual stresses in AM components, contributing to the optimization of processing parameters and post-treatment strategies. (AU)

• Processo FAPESP: 24/02502-8 - Estudo de otimização microestrutural e das propriedades mecânicas de amostras do aço ferramenta AISI-H13 processado por manufatura aditiva com feixe de laser programável
• Beneficiário: Suyanny Assunção Freire
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 24/14945-1 - Mitigação da austenita retida por modificação composicional do aço ferramenta AISI H13 processado por fusão em leito de pó
• Beneficiário: Fábio Faria Conde
• Modalidade de apoio: Bolsas no Brasil - Programa Fixação de Jovens Doutores
• Processo FAPESP: 24/02060-5 - Mitigação da austenita retida por modificação composicional do aço ferramenta AISI H13 processado por fusão em leito de pó
• Beneficiário: Éder Sócrates Najar Lopes
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/06045-0 - Manufatura avançada: exploração de métodos para controle e validação do processo de manufatura aditiva por fusão em leito de pó
• Beneficiário: Éder Sócrates Najar Lopes
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 19/06276-4 - Estudo de processamento e pós-processamento do aço AISI H13 por fusão em leito de pó: caracterização micro/nanoestrutural e mecânica
• Beneficiário: Eduardo Bertoni da Fonseca
• Modalidade de apoio: Bolsas no Brasil - Doutorado