A failed plastic chair was submitted to our failure analysis laboratory for examination. The right rear leg had broken off; however, the initial chair failure occurred on the left rear side. The left rear leg separated from the chair body due to poor bonding and molding porosity at the top of the leg. The failure […]
California failure analysis laboratory performed a failure analysis on a failed plastic chair. A 190 pound man sat in it and the right leg broke under him. This was a brittle plastic failure that went along a molding weld line. The fracture surface shows brittle failure in bending.
Plastic Failure Analysis Expert performs a failure analysis on a plastic “lawn chair” that collapsed when someone sat in it. The right arm separated from the seat. Upper left is a photograph of the subject chair with the separated leg. Fractography, top center photograph, indicates that the failure was progressive (i.e. a fatigue failure). Examination […]
Failure analysis expert witness examined a failed hospital chair. The chair failed during a breast X-ray examination. The chair had been altered 3 years prior to the failure, and the machine shop that had made the alterations was accused of causing the fatigue failure. Examination of the chair discovered hammer marks on a critical region […]