Laser beam processing for surface modifications

High power laser beam processing of metallic and nonmetallic surfaces offers considerable advantages over the conventional methods. The laser surface treatment involves local melting and evaporation, therefore, surface texture consisting of micro/nano poles can be generated under the control environment. Using the assisting gas during laser processing results in chemical reactions taking place at the treated surface, which in turn gives rise to chemical modification of the surface. Since laser surface treatment involves with texturing at high cooling rates and chemical modifications, the treated surface has superior characteristics in terms of hardness, wear resistance, and hydrophobicity. Consequently, in the present chapter some aspects of laser surface treatment process together with the characterization of the treated surface are presented. The morphological and metallurgical changes in the laser-treated layer are examined for various materials. Surface characteristics including friction coefficient, residual stress developed, and hydrophobicity are provided in detail. In addition, some case studies including surface treatment of phosphorous bronze, yttria-stabilized zirconia, and Rene 41 are presented in the light of the previous studies.