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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.

The automotive industry's ongoing effort to improve quality and reduce weight without added cost has led to the investigation of many medium strength steels. This study presents a comparison of continuously annealed Bake Hardenable Steels (BHS) with current DQSK production materials for outer panel applications. While all steels exhibit strength increases from work hardening during forming, BHS has a unique and ideal characteristic which produces an increase in yield strength due to strain aging during the paint baking process at the automotive assembly plants. This results in an increase in dent resistance. BHS is a desirable material for relatively flat outer panels which often receive only small strains during forming such as in doors, hoods and decklids. Improved durability against dents, dings, and palm printing are obtained in the BHS parts. Similarly, quality improvements are realized in the stamping and assembly plants by a decrease in handling and transit damage.

The static and impact load-carrying capability of resistance spot-welded HSLA and low carbon steel joints as influenced by loading rates, loading modes and welding schedules are presented. Peak load data at five testing speeds spanning between 1.6 × 10−4 km/h (10−4 mph) and 24 km/h (15 mph) for bare (1.5 mm; 0.060” gage) and galvanized (1.4 mm; 0.055” gage), 414 MPa (60 ksi)-yield HSLA steel and bare (1.3 mm; 0.050” gage) and galvanized (1.3 mm; 0.050” gage) low carbon steel showed an increase in maximum load with increasing test velocity. The tensile shear configuration exhibited the highest failure loads of the three joints tested, followed by the cross tension and coach peel joints. Results from under-, nominal-, and over-welded specimens suggested that slight over-welding in the expulsion region of the weld lobe could produce welds with similar, if not higher, loads as nominally-welded joints, whereas under-welding generally reduced the weld load-carrying capability.