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The laser deposition manufacturing (LMD) is a free-form metal deposition process, which allows generating a prototype or small series of near net-shape structures. Despite numerous advantages, one of the most critical issues of the technique is that produced pieces have a deleterious surface finish which requires post machining steps. Mechanical machining method such as milling and grinding has been used to improve the surface quality of the laser additive manufacturing components. However, the mechanical machining method has some drawbacks such as tool wearing and narrow-area difficult to machining. In this paper, we demonstrate the capability of continuous wave (CW) in polishing rough surface of additive manufactured TiAl alloy. The surface morphology, microstructures, corrosion resistance, micro-hardness and wear resistance of samples were characterized using a laser confocal microscopy (OM), scanning electron microscope (SEM), electrochemical analyzer, Vickers hardness machine, and wear tester, respectively. Results revealed that the surface roughness more than 16.06 μm could be reduce to less than 1.76 μm through laser polishing process. It was also found that a hardened layer about 600μm was produced on the TiAl alloy surface after laser finishing. The microhardness of the sample was improved about 8% compared with the mechanical milling method.
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