Herein, based on the ABAQUS commercial finite‐element analysis (FEA) software, a set of user subroutines is designed, and then a 3D FEA model is proposed to systematically and quantitatively investigate the effects of laser processing parameters on the evolution of molten pool structure and complicated thermal behavior during the selective laser melting (SLM) additive manufacturing of H13 die steel. The SLM experiments are conducted to verify the accuracy and reliability of simulation and reveal the densification behavior of SLM‐fabricated H13 die steel parts. The underlying thermal mechanism is revealed, and the relationship among laser processing parameters, thermal behavior, and densification is established. It is found that the densification behavior is highly sensitive to the applied volume energy density (VED). The densification level is effectively controlled by adjusting VED, hence obtaining the parts with excellent performance. The SLM‐fabricated specimens with nearly full dense cross sections are obtained, as the applied VED increases to 111 J mm⁻³. Research results found herein lie a foundation for the actual SLM processing of H13 die steel and provide a theoretical basis and technical support for the laser rapid prototyping of other die steels or even complete die parts.

中文翻译：

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金属粉末选择性激光熔融增材制造过程中的热行为和致密化机理

在此，基于ABAQUS商业有限元分析软件，设计了一套用户子程序，然后提出了一个3D FEA模型来系统和定量地研究激光加工参数对熔池结构演变的影响。 H13模具钢选择性激光熔融（SLM）增材制造过程中的热行为和复杂的行为。进行SLM实验以验证模拟的准确性和可靠性，并揭示SLM制造的H13模具钢零件的致密化行为。揭示了潜在的热机理，并建立了激光加工参数，热行为和致密化之间的关系。发现致密化行为对施加的体积能量密度（VED）高度敏感。通过调节VED可有效控制致密化程度，从而获得性能优异的零件。当施加的VED增加到111 J mm时，获得了SLM制成的具有几乎全密实横截面的试样⁻³。本文发现的研究结果为H13模具钢的实际SLM处理奠定了基础，并为其他模具钢甚至完整的模具零件的激光快速成型提供了理论基础和技术支持。