METHOD AND APPARATUS FOR PROVIDING A LAYER OF COMPRESSIVE RESIDUAL STRESS

摘要

The shot peening method and apparatus (Fig. 13) of the present invention utilizes control of the shot peening coverage to provide higher surface compression and comparable depth of compression to conventional 100% coverag e peening but with reduced cold working providing improved thermal stability a nd reduction in shot peening time and cost. A preferred embodiment of this invention employs x-ray diffraction (Fig. 13) residual stress and percent co ld work determinated by line broadening to establish the optimal degree of coverage for a given material and shot peening intensity.