Effects of Machine Variables on the Quality of Injection Moldings. An Interlaboratory Trial, 2: High Density Polyethylene

摘要

High-density, polyethylene tensile test pieces were produced at three establishments on different injection molding machines using specified conditions and a single injection mold. Large related differences in impact strength and reversion are found between batches of moldings, while no changes in tensile strength and morphology are detected. It is suggested that for crystalline materials, closer control of the cooling cycle may be necessary for the production of moldings with a reproducible standard of quality.