The paper introduces cracks of SMC DMC moulding product and their eliminating method from SMC DMC quality and moulding technology , product design, mould design and selection of release a-gents.
In the compression moulding technology, preheat and prepressing procedures are added to improve the flowability of the bond and physical and mechanical properties of the product.
In the practice, the controller has been successfully tested for the co - injection resin transfer molding process to reduce transverse resin mixing and to ensure complete wet - out.
moulding technological parameters are preheating temperature 100~110℃, preheating time 10~15 min, moulding pressure ≥25 MPa, moulding temperature 175~180℃, moulding time 0.8~1.0 min·mm~(-1), exhaust ≥3 times.
The moulding pressure was larger than 25MPa; The final moulding temperature was 175-180℃; The final moulding time was 0.8-1.0min/mm and the exhausting times were more than 3 times.
The experiment analyses the relationship between the resin viscosity changes and the roto-molding of the liquid resin through orthogonal experiment, this paper also studied the mechanism of void formation in roto-molding of long-fiber reinforced resin through some experiments.
Frustra were fabricated using carbon, E-glass, and hybrid carbon/E-glass reinforcements with a vinylester matrix using the resin transfer molding process.