Formning

Formning is a set of industrial processes that change the shape of a workpiece through plastic deformation without removing material. The goal is to produce components with a desired geometry, dimensional tolerance, and surface finish. Formning is common for metals, polymers, and ceramics; it is often performed at elevated temperatures to reduce material flow stress, though cold forming is also practiced for ductile metals.

Formning is typically divided into bulk forming and sheet forming. Bulk forming includes rolling, forging, extrusion, drawing, and upsetting, which change the cross-section or length of a billet. Sheet forming includes bending, deep drawing, stamping, and hydroforming, which shape thin sheets into complex profiles.

The process relies on tools such as dies, molds, and presses. Key parameters are material flow stress, temperature, strain rate, lubrication, friction, and die geometry. Quality depends on defects like wrinkling, earing, springback, laps, and cracks. Finite element analysis is commonly used to predict forming loads and identify potential issues.

Materials must possess adequate formability. Important properties include ductility, work hardening, anisotropy, and grain structure. Process choices depend on part geometry and required tolerances; deep drawing, for example, needs high ductility, while forging emphasizes strength and surface finish.

Formning has ancient roots in metalworking; modern formning uses computer-aided design, simulation, and automation to optimize processes, reduce waste, and control quality.