Laser peen forming for 2D shaping and micro adjustment

We present a methodology for automated forming of metal plates into freeformshapes using shot peening. The methodology is based on a simulation softwarethat computes the peening pattern and simulates the effect of its application.The pattern generation requires preliminary experimental characterizationof the treatment. The treatment is applied by a shot peening robot. The program for the robot is generated automatically according to the peening pattern. We validate the methodology with a series of tests. Namely, we form nine aluminum plates into doubly curved shapes and we also shape model airplane wing skins. The article describes the complete workflow and the experimental results.

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Shaping of Ceramics Using Residual Stresses

Materials Science Forum ◽

10.4028/www.scientific.net/msf.768-769.478 ◽

2013 ◽

Vol 768-769 ◽

pp. 478-483

Author(s):

Heiko Höpfel ◽

Wulf Pfeiffer

Keyword(s):

Shot Peening ◽

Surface Region ◽

Cyclic Strength ◽

Common Procedure ◽

Near Surface ◽

Peen Forming ◽

Deformation Work ◽

Stress States ◽

Underlying Mechanisms ◽

Localized Plastic Deformation

Shot peening is a common procedure used to improve the static and cyclic strength of metal components and for forming of thin walled components. The underlying mechanisms are localized plastic deformation, work hardening and the introduction of compressive stresses into the near-surface region. During the last decade we have been establishing damage-free shot peening processes for brittle materials such as ceramics. Based on these results we are now developing processes for peen-forming of ceramic components. This paper describes the first successful experiments aimed at shaping ceramic specimens using shot peening. Strips of different thicknesses, made of silicon nitride ceramic, were shot-peened using different shot sizes, peening pressures and coverage. The residual stress-depth distributions were determined using X-ray diffraction. Based on the experimentally determined stress states, the curvatures of the strips were calculated analytically and using Finite Element calculations (FEM). The results of the curvature measurements and calculations agree well.

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Numerical Modeling and Mechanism Analysis of Hybrid Heating and Shock Process for Laser-Assisted Laser Peen Forming

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4040914 ◽

2018 ◽

Vol 140 (11) ◽

Cited By ~ 1

Author(s):

Mingsheng Luo ◽

Yongxiang Hu ◽

Dong Qian ◽

Zhenqiang Yao

Keyword(s):

Thermal Stress ◽

Laser Heating ◽

Laser Peening ◽

Mechanism Analysis ◽

Coupled Modeling ◽

Bending Deformation ◽

Peen Forming ◽

Effects Of Temperature ◽

Capability Improvement ◽

Thermoelastic Plastic

Laser-assisted laser peen forming (LALPF) is proposed as a hybrid process to combine laser heating and laser peening to improve the bending capability of laser peen forming (LPF) effectively. To predict LALPF-induced bending deformation and mechanism of bending capability improvement, a sequentially coupled modeling approach is established by integrating three models, i.e., a thermoelastic-plastic model to predict the temperature, a dynamic model to obtain the eigenstrain of laser shock, and an eigenstrain model to predict the bending deformation. The effects of temperature, thermal stress, and thermal plastic strain of laser heating and the coupling effects on the bending deformation were investigated. The results show that the interaction of temperature and thermal stress are the dominant factors contributing to the improvement of bending capability.

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