Prediction of the optinum dimensions of the crystalline grains for the deep-drawing of metals

Abstract

The deep-drawing performance of metals must be taken into account for technological design: the deep-drawing performance is affected by the dimension of the crystalline.grains. To the best of the author's knowledge, study of the relationship between deep-drawing performance and the optimum dimension of the crystalline grains has not been reported in the open literature for non-ferrous metals and their alloys, especially copper and its alloys. In this paper, a method for predicting deep-drawing performance is advanced, in terms of the n- value and the r- value obtained by means of the uniaxial tensile test. The n- value and the r- value are different for different annealed microstructures, so that the optimum dimension of the crystalline grains for the deep-drawing of metals can be predicted before the establishing of the stamping technology. The method is convenient for engineers and technicians. In this work, the uniaxial tensile and deep-drawing test for H62 (ASTM 280), B19 (ASTM710) and L3 (ASTM 1050) have been carried out. The optimum dimension of the crystalline grains for H62, B19 and L3 are respectively 0.030–0.045 mm, 0.025–0.035 mm and 0.025-0.040 mm. The results of the deep-drawing tests have verified that the method proposed in this paper is credible.