Surface protection of light metals by one-step laser cladding with oxide ceramics

Today, intricate problems of surface treatment can be solved through precis ion cladding using advanced laser technology. Metallic and carbide coatings have been produced with high-power lasers for years, and current investiga tions show that laser cladding is also a promising technique for the produc tion of dense and precisely localized ceramic layers. In the present work, powders based on Al2O3 and ZrO2 were used to clad aluminum and titanium lig ht alloys. The compact layers are up to 1 mm thick and show a nonporous cas t structure as well as a homogeneous network of vertical cracks, The high a dhesive strength is due to several chemical and mechanical bending mechanis ms and can exceed that of plasma-sprayed coatings. Compared to thermal spra y techniques, the material deposition is strictly focused onto small functi onal areas of the workpiece. Thus, being a precision technique, laser cladd ing is not recommended for large-area coatings, Examples of applications ar e turbine components and filigree parts of pump casings.