In plastic injection molding, mold life is a critical factor that determines both production efficiency and product quality. Conventional metal molds provide excellent wear resistance and long service life, but they are costly and time-consuming to manufacture. Such characteristics limit their cost-effectiveness in low-volume production and product development stages. In contrast, rapid tooling is attracting growing attention due to its shorter lead time and lower manufacturing costs. However, the limited wear resistance and short service life of rapid tooling remain major challenges, which restrict its potential in practical applications. Improving the wear resistance and extending the service life of rapid tooling in injection molding is therefore an important research issue for both industry and academia. The maximum moldable content ranges from 13 to 25 vol% depending on the filler type. The Shore D hardness increases from about 80 HSD for unreinforced tooling to 90 HSD for SiC-reinforced tooling. Meanwhile, the steady-state friction coefficient decreases from approximately 0.72 to 0.50, and the wear depth reduces from 24 μm to 8 μm. Unreinforced molds show a surface roughness increase from about 2.1 nm to 8.2 nm after 50 cycles, while molds reinforced with PTFE, MoS₂, and WS₂ maintain lower roughness values of 6.2–7.6 nm, indicating that lubricating fillers effectively reduce friction and wear. Injection molding tests further show that unreinforced tooling develops surface cracks after about 200 cycles, whereas SiC-reinforced tooling delays crack initiation to around 300 cycles and limits surface roughness growth from 2.1 nm to below 7 nm after 50 cycles, demonstrating a significant enhancement in wear resistance and service life. This study contributes to sustainable development goals by promoting responsible production and consumption goal 12 through enhancing rapid tooling durability, reducing material waste, energy use, and extending mold service life in injection molding.
KUO et al. (Thu,) studied this question.