Influence of Defects on the Mechanical Properties of Metallic Coatings Obtained by Thermal Spraying: A Review

Thermally sprayed coatings are used as superior engineering materials, to prolong the service life of components and reduce manufacturing costs, but also significantly saving limited resources and energy, a technique capable to protect surfaces from erosive wear, corrosion, and enhance the tribological properties of a broad range of engineering materials. The study outlines the technological principle and process of thermal spray technique, and explores microstructural defects of thermal sprayed coatings, including pores, microcracks, unmelted particles, and oxides, exploring their formation mechanisms and effects. This paper also explores machine learning as a valuable tool that enables more accurate prediction of defect formation and supports the development of optimized spraying parameters.