The process, microstructure, and mechanical properties of hybrid manufacturing for steel injection mold components

Abstract

The traditional injection molding industry primarily utilizes subtractive manufacturing processes to ensure the quality of molds, which often requires high expenses. With the rapid development of additive manufacturing, the integration of additive and subtractive processes, known as hybrid manufacturing, has emerged as a new trend. This new approach necessitates comprehensive quality characterization of the produced components. This paper investigates the feasibility of hybrid manufacturing for core mold components subjected to cyclic loading conditions, utilizing laser cladding and machining. The study evaluates multiple indicators through a blend of experimental and simulation methods to assess and validate the effectiveness and practicality of the manufacturing process. In summary, the findings indicate that laser cladding technology provides high-quality, dense cladding layers with an average porosity below 0.1 %, demonstrating strong potential for industrial applications. Electron Back Scatter Diffraction (EBSD) analysis shows that the cladding layer has a larger grain size than the substrate material, consistent with microhardness tests that reveal lower hardness values in the cladding layer (mostly below 500 HV) compared to the substrate area (exceeding 500 HV) due to the process's high temperatures. Fatigue tests revealed that fit type has a significant impact on fatigue performance. Although the simulated fatigue life curve predicted a shorter life than observed experimentally, it followed a similar trend.