The LDH Test to Evaluate Sheet Metal Formability - Final Report of the LDH Committee of the North American Deep Drawing Research Group

The Limiting Dome Height (LDH) test is a formability test designed for the sheet metal industry. It tests the material in or near plane strain. Under properly controlled conditions, it appears to be as stable as other classic material tests. The simplicity of the procedure and its simulative nature make it a good test for the statistical monitoring of incoming material in a stamping production environment.

Being a simulative test, it integrates the effects of parameters such as work hardening, ductility and friction into a single numerical value, the LDH value. The test does not differentiate between the variations of different parameters, but serves as an indicator that something has changed. Under controlled conditions, it is a good measure of the material performance under the most common failure mode, plane strain. However, the LDH test cannot be used to express or specify desired material characteristics.