5. Conclusions

The formability of AZ31B magnesium alloy sheets was investigated in the present study by the tensile test, the deep drawing test and the cold stamping test of cell phone housing. The research results indicate that, compared with the as received sheets, the RUB processed sheets exhibit a lower yield strength, a lower yield ratio, a larger fracture elongation, a smaller Lankford value (r-value), a larger strain hardening exponent (n-value) and a superior stretch formability. The LDR of the RUB processed sheets can reach 1.5 at room temperature. It is verified that the magnesium alloy sheet with a tilted texture obtained by RUB process has favorable formability at room temperature. It was also confirmed that cell phone housing could be produced successfully in crank press using the RUB processed AZ31B sheet by the stamping process.

Acknowledgements

Sincere thanks are given to the National Natural Science Foundation of China under Grant no. 50504019, Natural Science

Foundation of CQ CSCT under Grant no. 2008BB4040 and Scientific and Technological Project of CQ CSCT under Grant no. 2008AA4028 for their supports.

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