Research Abstract |
1.The fatigue strength of the unpeened specimens of Ti-6Al-4V alloy was found to be 490 MPa, 430 MPa, 410 MPa and 440 MPa at 20゚C,250゚C,350゚C and 450゚C,respectively. The respective values for the shot peened specimens were 620 MPa, 520 MPa, 440 MPa and 260 MPa. The fatigue strength was definitely increased by shot peening at 20゚C,250゚C and 350゚C,and the increments were about 27%, 21% and 7%, respectively. The fatigue strength, houever, was remarkably decreased by shot peening at 450゚C,and its decrement reached about 41%. 2.The fatigue strength of the specimens including small artificial defects was found to be 290 MPa, 230 MPa, 230 MPa and 200 MPa at 20゚C,250゚C,350゚C and 450゚C,respectively. The respective values for the shot peened specimenswere 560 MPa, 520 MPa, 470 MPa and 300 MPa, and the increments were about 93%, 126%, 104% and 50%, respectively.
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