In order to solve the fatigue failure of the valve lever fixed in certain aeroengine, the technology of laser shock processing (LSP) on the valve lever was studied. Then, the valve levers of prototype and valve levers processed by LSP, shot peening (SP) and enlarge R were applied to vibration fatigue test. The results show that at the vibrating stress level of 317�~MPa, compared with the prototype, LSP, SP and enlarge R could increase the fatigue life by 424%, 289% and 36% distinguishably. The effectivity, stability and operability of LSP make it the best way to decrease fatigue failure of the valve lever at the present time. The LSP strengthening effect on valve lever is attributed to the low roughness, the high numerical compressive residual stress field about 1.4�~mm in depth and the grain refinement to nanocrystal accompanied with high density dislocation. The three factors above are the main reasons what LSP could prolong the fatigue life of valve lever, because that they work together could efficiently release the stress concentration at R area as well as restrain the initiation and propagation of fatigue crack.
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