Laser additive manufacturing in surface modification of metals

Additive Manufacturing (AM) offers lots of advantages when compared to other manufacturing processes, such as high flexibility and ability to produce complex parts directly from the Three Dimensional (3D) Computer-Aided Design (CAD) model. Producing highly complex parts using traditional manufacturing processes is difficult, and it requires it to be broken down into smaller parts, which consumes lots of materials and time. If this part needs to have a surface with improved property or a surface made of composite materials, it has to be done by employing another manufacturing process after the parts are completed. AM, on the other hand, has the ability to produce parts with the required surface property in a single manufacturing run. Out of all the AM technologies, Laser Additive Manufacturing (LAM) is the most commonly used technique, especially for metal processing. LAM uses the coherent and collimated properties of the laser beam to fuse, melt, or cut materials according to the profile generated from the CAD image of the part being made. Some of the LAM techniques and their mode of operations are highlighted in this chapter. The capabilities of using LAM for surface modification of metals are also presented in this chapter. A specific example is given as a case study for the surface modification of titanium alloy (Ti6Al4V) with Ti6Al4V/TiC composite using laser material deposition process - an important LAM technology. Ti6Al4V is an important aerospace alloy, and it is also used as medical implants because of its corrosion resistance property and its biocompatibility.