Randschichtoptimierung von Kupferlegierungen: Minimierung von Oberflächenschädigungen durch korrosive und erosive Beanspruchungen

Complex aluminium bronzes (Cu-Al-Ni-Fe, Cu-Al-Mn-Fe-Ni alloy systems) are used for manufacturing prefabricated parts which must have a high resistance against wear and corrosion apart from high mechanical properties. Despite the favourable combination of mechanical properties and surface properties, the surface damages of these materials, which are caused by the use during operation, cannot be avoided. The extent of these damages determine the duration life of the workpieces. The high resistance of the alloys against wear and corrosion is only demanded by the surface. Therefore, it seems to be useful to fulfill the solicitation of the prefabricated parts by using a surface treated material. In the present paper, the surface melting was effected by means of a laser beam. The maximum value of the hardening turned out to be determined by the transformation behaviour of the alloy. The surface melting with laser beam partly optimised the corrosion properties and improved especially the cavitation erosion behaviour.