14th International Conference on Shot Peening

Development of laser peening for surface enhancement and shape control:

modeling, experiments & applications

Yongxiang Hu

School of Mechanical Engineering, Shanghai Jiao Tong University,

huyx@sjtu.edu.cn

Biography:

Dr. Yongxiang Hu received his B.S. degree from Nanjing University of Science & Technology in 2003 and his Ph.D. degree in Mechanical Engineering from Shanghai Jiao Tong University in 2008. Then he worked as a postdoctoral fellow at Wright State University in USA and continued his research at SJTU. Currently, he has served as a full professor since 2020 and vice-dean of Mechanical Engineering School since 2021. His research interests include laser peening, laser peen forming, laser-induced forward printing, etc. The goal of his research is to gain a comprehensive understanding of the mechanical behavior of the material under laser peening, to ultimately improve process quality. His research has published more than 50 journal papers and holds 12 patents. For his work, he has received several rewards, including NSFC Excellent Young Scholars.

Abstract:

Laser peening is proposed as an effective mechanical process to improve fatigue resistance for components and shape panels with complex geometry in industry. The process design of laser peening with assistance modeling is of great importance to reduce development time and cost for applications in high-value components. This presentation will introduce our research work on the modeling and optimization of the laser peening process for fatigue resistance enhancement and complex shape forming in the past ten years.

Forward modeling of laser peening process spot-by-sport was developed to capture the transient response of the material and recently it has been improved by integrating crystal plasticity including dislocation behavior under high strain rate conditions.

To overcome high computation costs, eigenstrain has been developed to predict the effect of large-scale laser peening more efficiently. Moreover, the static Crystal Plasticity modeling method is introduced recently to predict the mechanical properties of AA2195-T6 Friction Stir Welded Joints after laser peening including compressive residual stresses, work hardening, and crystal morphology evolutions. Experimental and theoretical approaches are combined to quantify the strengthening contributions of laser-peening-induced near-surface local plastic deformation effects on the enhancement of local and overall mechanical properties of AA2195-T6 friction stir welded joints.

Furthermore, eigen-moment, derived from eigenstrain, is proposed to describe the bending behavior of metal plates in laser peen forming.

To achieve process planning of laser peen forming, the distributed eigen-moment on two surfaces of the plates is prescribed, and an optimization framework is developed for laser peen forming with complex shapes. Finally, several applications for laser peening of large-scale components will be introduced to demonstrate the model capabilities.