The AZ31 magnesium alloy sheets obtained by multi-pass hot rolling were applied to cold rolling and the maximum single pass cold rolling reduction prior to failure of AZ31 magnesium alloy was enhanced to 41%. Larger s...The AZ31 magnesium alloy sheets obtained by multi-pass hot rolling were applied to cold rolling and the maximum single pass cold rolling reduction prior to failure of AZ31 magnesium alloy was enhanced to 41%. Larger single pass rolling reduction led to weaker texture during the multi-pass hot rolling procedure. The sheet obtained showed weak basal texture, while the value was only 1/3-1/2 that of general as-rolled AZ31 Mg alloy sheets. It was beneficial for the enhancement of further cold rolling formability despite of the coarser grain size. The deformation mechanism for the formation of texture in AZ31 magnesium alloy sheet was also analyzed in detail.展开更多
The theory of grey systems is a new technique for performing prediction, relational analysis and decision making in many areas. The grey relational analysis was used to optimize the deep-drawing process parameters wit...The theory of grey systems is a new technique for performing prediction, relational analysis and decision making in many areas. The grey relational analysis was used to optimize the deep-drawing process parameters with considerations of the multiple response （the wrinkle, crack and thinning variation）. The deep-drawing parame- ters, such as the blank holding force （Fhh）, the radii of punch and die （R1.R2）, the coefficients of friction （μ1,μ2,μ3） are considered. An orthogonal array is used for the experimental design. The multiple response values are ob- tained making use of finite element analysis （FEA）. Optimal process parameters are determined by the grey rela- tional grade obtained from the grey relational analysis for multi-performance characteristics （the wrinkle, crack and the thinning）. The analysis of variance （ANOVA） for the grey relational grade is implemented. The results show that the quality of stamped parts can be improved effectively through the new approach. The grey relational analysis can be applied in sheet metal forming.展开更多
文摘The AZ31 magnesium alloy sheets obtained by multi-pass hot rolling were applied to cold rolling and the maximum single pass cold rolling reduction prior to failure of AZ31 magnesium alloy was enhanced to 41%. Larger single pass rolling reduction led to weaker texture during the multi-pass hot rolling procedure. The sheet obtained showed weak basal texture, while the value was only 1/3-1/2 that of general as-rolled AZ31 Mg alloy sheets. It was beneficial for the enhancement of further cold rolling formability despite of the coarser grain size. The deformation mechanism for the formation of texture in AZ31 magnesium alloy sheet was also analyzed in detail.
基金The National Natural Science Foundation of China (No50475020)
文摘The theory of grey systems is a new technique for performing prediction, relational analysis and decision making in many areas. The grey relational analysis was used to optimize the deep-drawing process parameters with considerations of the multiple response （the wrinkle, crack and thinning variation）. The deep-drawing parame- ters, such as the blank holding force （Fhh）, the radii of punch and die （R1.R2）, the coefficients of friction （μ1,μ2,μ3） are considered. An orthogonal array is used for the experimental design. The multiple response values are ob- tained making use of finite element analysis （FEA）. Optimal process parameters are determined by the grey rela- tional grade obtained from the grey relational analysis for multi-performance characteristics （the wrinkle, crack and the thinning）. The analysis of variance （ANOVA） for the grey relational grade is implemented. The results show that the quality of stamped parts can be improved effectively through the new approach. The grey relational analysis can be applied in sheet metal forming.
