Deformation Processes at the Surface of a Nickel Alloy Subjected to Nanosecond Laser Pulses

The effects on the surface of a nickel superalloy that are caused by the action of pulsed radiation from an Nd:YAG laser with a wavelength in the ultraviolet range (0.355 μm) and a pulse duration of 10 ns are studied. The surface layer is found to rise in a subthreshold irradiation regime. Traces of high-temperature plastic deformation via grain-boundary sliding and crystallographic slip are detected in the spot zone. The joints of nickel alloy samples with preliminary laser treatment are subjected to diffusion welding and mechanical tests; as a result, a noticeable improvement in the weld quality as compared to untreated samples is shown.