Laser Treatment

There a four uses of laser technology to modify the surface properties of metals. One method is to harden the surface using laser heating which enhances thermal diffusion at the surface. A second technique is to use laser heating to melt the surface which is then rapidly quenched to modify the surface structure. A third method uses a laser to melt the surface and alloying elements are added to the surface melt effectively creating a different material at the surface. The fourth method makes use of a laser’s shock effect to induce compressive stresses within a metal’s surface. This has the same effect as shot peening with the major difference that it can produce residual compressive stresses to a depth of approximately 1.0 mm, resulting in higher fatigue lives. This method is referred to as “laser peening” or “laser shock processing.”