A study on surface integrity of laser cladding coatings post-treated by ultrasonic burnishing coupled with heat treatment

• DOI: 10.1016/j.matlet.2021.131136
• Publication Date: 2021-10-30T14:51:15Z
• Authors: Jiatian Wang; Changsheng Zhang; Xuehui Shen; Jianqun He
• Keywords: 0203 mechanical engineering; 02 engineering and technology

Abstract Laser cladded parts generally need to be post-machined due to its poor surface finishing and some inherent defects. The commonly used post-machining methods are turning and grinding, which is capable of lowering surface roughness of cladding coatings but incapable of reducing defects. Three processes were proposed and explored for the post-treatment of Fe-based laser cladding coatings, i.e., ultrasonic burnishing at room temperature (UB); ultrasonic burnishing at medium temperature (UWB); ultrasonic burnishing at medium temperature coupled with sequent heat treatment (UWB/HT). As a result, UWB/HT improved the surface integrity of cladding coatings most effectively. In comparison to the control sample, the surface roughness, grain size and porosity of UWB/HT-treated sample decreased by 82.76%, 64.18% and 92.16%, respectively, and the hardness increased by 29.91%. The induced compressive residual stress of the UWB/HT sample increased from −19.12 MPa to −333.59 MPa.