Abstract: The state of the art of laser radiation on LY12CZ Ai-alloy is briefly introduced. The optimization of radiative parameter, the comparison test of fatigue life, the test of crack propagation, the analysis of dislocation cell move, and all the results show that the effect of radiative parameters on fatigue life is significant. The fatigue life can be obviously increased only in a specific range of radiative parameters, and in such a case the ability of anti fatigue-fracture can be considerably increased.

Key words: laser, dislocation cell, fatigue life, crack propagation