Question

Explain how the processing parameters for INJECTION MOULDING can influence the tensile strength for a given polymer, explain this in terms of polymer properties.

Answer 1

Injection molding is the most commonly used manufacturing process for the fabrication of plastic parts. The process requires the use of an injection molding machine, raw plastic material, and a mold. The plastic is melted in the injection molding machine and then injected into the mold, where it cools and solidifies into the final part.

The processing parameters involved in injection moulding process are melting temperature, mould temperature, clamping force, injection pressure, injection speed, packing pressure, holding pressure etc.

Many experiments conducted have determined the relationship b/w the tensile strength and processing parameters. Injection pressure has significant influence on tensile strength, while the injection speed has no effect. The optimum
parameter that can maximize the tensile strength is packing pressure.