Moulding at Mazda

As part of its efforts to reduce vehicle weight, Mazda Motor Corporation has developed a plastic moulding technique that enables the weight of plastic parts used in vehicles to be reduced.

The company claims that the manufacturing technique cuts the consumption of plastic resins used as raw material by approximately 20 to 30 per cent, with associated reductions in weight.

The most common manufacturing method for producing automobile plastic parts is injection moulding. Mazda’s improved injection moulding process involves mixing supercritical fluids (SCF) made from common inert gases such as nitrogen or carbon dioxide with the plastic resin raw material.

The process raises the fluidity of the liquid plastic resin and causes it to expand rapidly when injected into a mould. As a result, smaller amounts of raw material resin are needed to fill moulds.

Furthermore, by using a core back expansion moulding process, substantially less material is needed to manufacture plastic parts that are lighter and have equal or greater strength and rigidity characteristics compared to conventional, non-foamed parts.