Many currently produced plastic automotive parts use glass fiber reinforced plastic for enhanced strength and reduced vehicle weight. Apart from glass fiber, there are many manufacturing process factors concerning the production of the glass fiber reinforced plastic parts and their characteristics. This paper employed Taguchi's method, a correlation analysis, and an axiomatic design to study the optimizing process for glass fiber-reinforced plastic parts. The major factors affecting the characteristics of the plastic-based automotive parts were determined, and the optimal conditions for the parts were deduced.

Many automakers are developing instrument panels with embopatterns to make more luxurious interior parts for compact cars. The economical male vacuum forming process helps to make parts with embo-patterns price competitive, but embo-pattern loss is greater than that observed with a female vacuum forming process. In the current study, we developed a thermoplastic olefin blend embo-pattern sheet, cross-linked by electron beam irradiation, to minimize embo-pattern loss incurred during part forming in the male vacuum process. The electron beam irradiation dose and materials mixture in the sheet were optimized, improving the retention rate of embo-patterns by almost 3-fold with an electron beam irradiation dose of 80 kGy. At 80 kGy, the product met all property requirements of sheets developed for instrument panel applications and the performance evaluation for airbag deployment. Additionally, this instrument panel production is expected to result in improved price competitiveness, with a savings of more than 10%.