Plastics

A cracked or broken plastic part can contain physical evidence about how the failure developed. Fracture-surface features, crack location, part geometry, thickness changes, molding features, contamination, and deformation may be evaluated alongside material specifications, manufacturing records, and service history. Microscopy, mechanical testing, or other material-analysis methods may provide additional evidence when visual examination alone is not sufficient.

Molding conditions can affect a plastic component's structure, dimensions, and mechanical performance. Temperature, pressure, cooling rate, material drying, flow behavior, mold geometry, and cycle conditions may contribute to voids, weld lines, residual stresses, incomplete filling, dimensional variation, or other defects. An expert may compare production records, process parameters, and the failed component to assess whether manufacturing conditions contributed to the problem.

Yes. Heat, ultraviolet radiation, moisture, chemicals, repeated loading, and prolonged stress can change the physical or chemical properties of plastics over time. The extent of those changes depends on factors such as the polymer, additives, duration and severity of exposure, and intended use. Analysis of the failed material and appropriate reference data can help determine whether environmental degradation contributed to the observed damage.