Abstract

Laser cladding is a convenient process for altering the surface properties of a solid in order to increase its hardness or corrosion resistance. The technique consists of blowing a stream of fine powder through a nozzle onto the laser-generated melt pool of a moving substrate. The final surface quality depends on a number of parameters, including the laser beam intensity, the powder-beam distribution, the flow stability, and the nature and pressure of the gas in the interaction volume. We have investigated the propagation of a high-power laser beam through a stream of powder. Experiments have been conducted for for CO₂ and Nd:YAG lasers. Figure 1 shows the experimental setup. The following detection devices were used: a CCD camera, a calorimeter, a spectrograph, photodiodes, and a pyrometer.

© 1995 Optical Society of America