Surface modification techniques for microstructural enhancement in metal additive manufacturing

Metal additive manufacturing (AM) has impacted the fabrication of intricate metal parts offering exceptional design freedom. However, the microstructure characteristics of additively generated components significantly influence the mechanical properties and performance. Surface modification techniques have emerged as the key to enhancing the microstructure characteristics and optimising the mechanical properties of metal AM products. This chapter focuses on exploring mechanical surface treatment methods (shot peening, laser shock peening and ultrasonic impact treatment) and their effect on microstructural characteristics such as phase transformation, grain orientation and grain morphology (size, composition). The enhanced techniques proposed in this study have the potential to customise the microstructure aspects of additively built metal components, allowing for the manufacturing of parts with improved performance, durability and tailored surface features. These technological advancements will have significance in a variety of industries, including aerospace, automotive and biomedical, where microstructural control is crucial for obtaining optimal performance in metal AM applications.