Busi Matteo, Kalentics Nikola, Morgano Manuel, Griffiths Seth, Tremsin Anton S, Shinohara Takenao, Logé Roland, Leinenbach Christian, Strobl Markus
Paul Scherrer Institute, Laboratory for Neutron Scattering and Imaging, Forschungsstrasse 111, 5232, Villigen, Switzerland.
Thermomechanical Metallurgy Laboratory-PX Group Chair, Ecole Polytechnique Fédérale de Lausanne (EPFL), 2002, Neuchâtel, Switzerland.
Sci Rep. 2021 Jul 21;11(1):14919. doi: 10.1038/s41598-021-94455-3.
Laser powder bed fusion is an additive manufacturing technique extensively used for the production of metallic components. Despite this process has reached a status at which parts are produced with mechanical properties comparable to those from conventional production, it is still prone to introduce detrimental tensile residual stresses towards the surfaces along the building direction, implying negative consequences on fatigue life and resistance to crack formations. Laser shock peening (LSP) is a promising method adopted to compensate tensile residual stresses and to introduce beneficial compressive residual stress on the treated surfaces. Using neutron Bragg edge imaging, we perform a parametric study of LSP applied to 316L steel samples produced by laser powder bed fusion additive manufacturing. We include in the study the novel 3D-LSP technique, where samples are LSP treated also during the building process, at intermediate build layers. The LSP energy and spot overlap were set to either 1.0 or 1.5 J and 40[Formula: see text] or 80[Formula: see text] respectively. The results support the use of 3D-LSP treatment with the higher LSP laser energy and overlap applied, which showed a relative increase of surface compressive residual stress (CRS) and CRS depth by 54[Formula: see text] and 104[Formula: see text] respectively, compared to the conventional LSP treatment.
激光粉末床熔融是一种广泛用于生产金属部件的增材制造技术。尽管该工艺已达到所生产部件的机械性能与传统生产部件相当的水平，但它仍然容易在沿构建方向的表面引入有害的拉伸残余应力，这对疲劳寿命和抗裂纹形成能力有负面影响。激光冲击喷丸（LSP）是一种用于补偿拉伸残余应力并在处理过的表面引入有益压缩残余应力的有前景的方法。利用中子布拉格边缘成像技术，我们对应用于通过激光粉末床熔融增材制造生产的316L钢样品的LSP进行了参数研究。我们在研究中纳入了新颖的3D-LSP技术，即在构建过程中的中间构建层对样品进行LSP处理。LSP能量和光斑重叠分别设置为1.0焦耳或1.5焦耳以及40%或80%。结果支持使用施加较高LSP激光能量和重叠的3D-LSP处理，与传统LSP处理相比，其表面压缩残余应力（CRS）和CRS深度分别相对增加了54%和104%。
