High-temperature deep drawability of pure molybdenum sheet in vacuum environment

Uniaxial tensile tests for pure molybdenum sheets with thickness of 2.0 mm were conducted in a temperature range between 25 and 870℃, and the finite element model for hot deep drawing of molybdenum plate was established. Based on the contrastive analysis of FEM and experiments, the relationship between friction coefficient and temperature was confirmed, and the effects of forming temperatures, lubricating conditions, blank-holder gap and die dimensions on deep drawing process were investigated, and then the vacuum hot deep drawing tests were carried out with optimized process parameters. The results indicate that lubrication has the most prominent effect on the deep-drawing process, followed by the forming temperature. The limiting drawing ratio can be raised up to 1.94 with the optimum parameters including forming temperature 870℃, drawing speed 30 mm/min and blank-holder gap 2.5 mm under lubricated condition.