A Review of Additive Manufacturing Post-Treatment Techniques for Surface Quality Enhancement

Abstract

Additive manufacturing (AM), also known as 3D printing, produces an object layer by layer with the application of a computer-controlled method. AM creates an object by adding material to a solid block until the finished product is created. AM manufacturing benefits including design flexibility, creativity, rapid prototyping, high productivity, reduced manufacturing cycle, etc. However, AM products have physical quality flaws such as surface roughness, inaccurate dimensioning, porosity, staircase effects, etc. Therefore, there is a need to carry out post-treatment on the AM fabricated components to correct their flaws before they can be used. Seventeen different post-treatment methods (PTM) on AM fabricated components were discussed in this review study. Each of these PTMs, however, has its advantages and disadvantages. The results obtained from the study show that chemical PTM has the ability to improve surface roughness easily, laser polishing can be used to reduce the staircase effects, and thus reduce surface roughness significantly and increase the hardness of AM fabricated component parts. Mechanical PTM helps to join the layers of AM components and improve their toughness, while subtractive machining PTM improves surface quality. Thermal PTMs are used to improve corrosion resistance, reduce surface roughness, eliminate staircase effects, etc. The discussion of various PTMs is clearly highlighted to serve as a guide for AM stakeholders.