Schubnell Jan, Carl Eva-Regine, Sarmast Ardeshir, Hinterstein Manuel, Preußner Johannes, Seifert Marco, Kaufmann Christoph, Rußbüldt Peter, Schulte Jan
Fraunhofer Institute for Mechancis of Materials IWM, Woehlerstr. 11, 79109 Freiburg, Germany.
Fraunhofer Institute for Material and Beam Technology IWS, Winterbergstr. 18, 01277 Dresden, Germany.
Materials (Basel). 2023 Oct 19;16(20):6769. doi: 10.3390/ma16206769.
Laser shock peening (LSP) is a mechanical surface treatment process to modify near-surface material properties. Compared to conventional shot peening (SP) the process parameters can be finely adjusted with greater precision and a higher penetration depth of compressive residual stresses could be reached. However, high process times of LSP leads to high production costs. In this study, ultrafast LSP (U-LSP) with an ultrafast laser source (pulse time in the picosecond range) was applied on specimens made of X5CrNiCu15-5 and AlZnMgCu1.5. The surface characteristics (surface roughness) and surface-near properties (microstructure, residual stresses, and phase composition) were compared to the as-delivered condition, to conventional laser shock peening (C-LSP), and to SP, whereas metallographic analyses and X-ray and synchrotron radiation techniques were used. The process time was significantly lower via U-LSP compared to C-LSP. For X5CrNiCu15-5, no significant compressive residual stresses were induced via U-LSP. However, for AlZnMgCu1.5, similar compressive residual stresses were reached via C-LSP and U-LSP; however, with a lower penetration depth. A change in the phase portions in the surface layer of X5CrNiCu15-5 after C-LSP compared to SP were determined.
激光冲击强化（LSP）是一种用于改变近表面材料性能的机械表面处理工艺。与传统喷丸强化（SP）相比，该工艺参数可以更精确地微调，并且可以达到更高的压缩残余应力穿透深度。然而，LSP的加工时间长导致生产成本高。在本研究中，使用超快激光源（皮秒级脉冲时间）的超快LSP（U-LSP）应用于由X5CrNiCu15-5和AlZnMgCu1.5制成的试样。将表面特性（表面粗糙度）和近表面性能（微观结构、残余应力和相组成）与交付状态、传统激光冲击强化（C-LSP）和SP进行了比较，同时使用了金相分析以及X射线和同步辐射技术。与C-LSP相比，U-LSP的加工时间显著缩短。对于X5CrNiCu15-5，U-LSP未产生明显的压缩残余应力。然而，对于AlZnMgCu1.5，C-LSP和U-LSP产生的压缩残余应力相似；然而，其穿透深度较低。确定了与SP相比，C-LSP后X5CrNiCu15-5表面层相比例的变化。
