A study on trimming of aluminum autobody sheet and development of a new robust process eliminating burrs and slivers

Small pieces of metal are generated during trimming of automotive body panels. Commonly referred to as slivers, these pieces can be imprinted into the surface of stamped panels. This may require metalfinish of every stamped exterior panel. The objective of the paper is to study the influence of trimming conditions on quality of trimmed surface and to modify the trimming process to eliminate slivers and burrs from trimmed surface. This objective is being accomplished through numerical simulation of the blank fracture and experimental study of trimmed surface formation. Suggested solution includes two measures: (1) building an elastic support of the offal eliminating bending of the part of the blank being trimmed off; (2) creating the preference of crack propagation from the lower shearing edge by machining a small radius on the upper shearing edge.

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