Metal additive manufacturing (MAM) technology has been developed rapidly in aerospace

ship building

automobile manufacturing and bio-medical industries. However

MAM technology is characterised by a number of issues that are slowing its wider implementation. The peculiar microstructure of MAM components leads to anisotropy

the components are affected by residual stresses and distortion during MAM

and also it is easy to produce cracks and holes. Therefore

this paper mainly introduces several methods and techniques for improving the microstructure and performance of metal additively manufactured materials

such as optimization of process parameters

post-treatment

particles introduction

ultrasonic interference technique

ultrasonic impact treatment

rolling and ultrasonic micro-forging technique.