LASER CLADDING OF FUNCTIONALLY GRADED MATERIALS: DESIGN AND MANUFACTURING OF MULTI-POWDER FEEDER FOR MANUFACTURING FUNCTIONALLY GRADED MATERIALS THROUGH LASER CLADDING PROCESS

Abstract

Laser cladding is a laser based additive manufacturing process which is currently employed for bonding dissimilar materials. The materials which are bonded together are mostly metals or alloys. The process of laser cladding involves melting of metals / alloys through heat provided by laser beam. The melted materials are added on a substrate in such a manner that the added materials form covalent bonds with substrate thus providing high strength of bonding between added materials and substrate. The process of laser cladding mainly requires two sub-systems namely: material feeding system and laser application system. The material feed system can further be classified as powder feed or wire feed systems. The powder-based material feeding is mostly employed for laser cladding nowadays. It encompasses supply of either one powder to form single material surface coat or the supply of multi-powders to form multi material surface coats on the substrate. In this study, a multi-material powder feeding system is designed and fabricated for imparting laser cladding to three dissimilar powder materials. An electronic control mechanism is introduced in the powder feeding system which will provide control of changing the feed rate of the powder supply. The control of feed rate provides the capability of manufacturing functionally graded materials by changing the composition of powders during or before the machine operation. The multi-powder feeder machine can feed three different materials (at controllable varied flowrates) for manufacturing functionally graded materials. This thesis has been structured in four fundamental sections. First section comprises of CAD (Computer Aided Design) Modelling and Structural Analysis of proposed multi-powder feeder in PTC Creo. Second section focuses on the practical manufacturing of multi-powder feeding machine and integrating the control mechanism of electro-mechanical control system using LabVIEW graphical user interface. Third section shows the obtained results from conducted experiments. The fourth and final section highlights some of the potential industrial applications of proposed project.