PREPARATION AND MICROSTRUCTURE OF LASER-GLAZED AL-BASED ALLOYS

From the metallurgical as well as from the economic/industrial point of view the laser glazing of Al-based alloys represents a new and at the same time increasing interesting field. If it could be possible to vitrify low-price and suitable Al-alloys with laser light, this could open attractive fields of application, especially for wear-resisting parts (for example in engines). Based on a short discussion of the most important metallurgical aspects which occur during the laser treatment like rapid melting, mixing and rapid quenching the potentiality and limits of laser amorphization of Al alloys will be analyzed. Thereby, the results of experiments with Al-Y-Ni alloys are of special interest. It will be shown that it is possible to vitrify the surface if the process parameters and the pretreatment of the material are well chosen. In this case the maximum hardness amounts to 1000 HV 0.025.