摘要
In the present work, the effects of trace element Sr on the microstructure, tensile properties, fractography and morphology of the eutectic Si of ZL114A （Al-7Si） cast alloy were investigated. The cast ZL114A aluminum alloy was prepared using a metal mold, and then heat treated with the T6 technique. The test results of mechanical properties show that modification element Sr can improve significantly the ultimate tensile strength, elongation and hardness of the ZL114A-T6 aluminum alloy. By adding 0.04%Sr, the values of the tensile strength Rr,, elongation A and hardness HB increase from 230 MPa, 1% and 65 to the maximum of 305 MPa, 8%, and 100, respectively. SEM analysis indicates that the near tensile fracture surface on longitudinal section of the ZL114A- T6 alloy reveals a transgranular fracture mode without Sr modification, while the tensile fracture is an intergranular fracture mode after Sr modification. The morphology of the eutectic Si phase is changed from acicular to fine fibrous.
In the present work, the effects of trace element Sr on the microstructure, tensile properties, fractography and morphology of the eutectic Si of ZL114A (Al-7Si) cast alloy were investigated. The cast ZL114A aluminum alloy was prepared using a metal mold, and then heat treated with the T6 technique. The test results of mechanical properties show that modification element Sr can improve significantly the ultimate tensile strength, elongation and hardness of the ZL114A-T6 aluminum alloy. By adding 0.04%Sr, the values of the tensile strength Rm, elongation A and hardness HB increase from 230 MPa, 1% and 65 to the maximum of 305 MPa, 8%, and 100, respectively. SEM analysis indicates that the near tensile fracture surface on longitudinal section of the ZL114A-T6 alloy reveals a transgranular fracture mode without Sr modification, while the tensile fracture is an intergranular fracture mode after Sr modification. The morphology of the eutectic Si phase is changed from acicular to fine fibrous.
基金
financially supported by the National Key projects of China (G09003.8-4)
