Abstract

Laser shock processing (LSP), a technique for metals strengthening, induces a compressive residual stress field which improves materials mechanical behavior mainly fatigue properties. One of the research lines of our working group focuses on the simulation and validation of the effect of LSP surface treatment, where computational tools such as Abaqus and fe safe are very useful. We evaluate the viability of applying LSP to extend the fatigue life of components with and without concentrator of stress. For the LSP treatment a convergent lens was used to deliver 1.0 J and 6 ns laser pulses by a Q-switch Nd: YAG laser, operating at 10 Hz with 1064 nm of wavelength and density of 2500 pulses/cm2. The pulses were focused to a diameter of 0.9 mm on the surface of the samples without coating. The residual stress field produced by the LSP process was estimated by a finite element simulation, and, on the other hand, residual stress distribution as a function of depth is evaluated by the hole drilling method for validation. A fatigue analysis of specimens is conducted using the commercial code fe-Safe and different multiaxial fatigue criteria to predict fatigue lives of samples with and without LSP.  A good comparison of the simulation and experimental results was observed.

Presenter Bio - Vignaud Granados

Vignaud is a doctor in Science and Technology with a specialty in design and development of mechanical systems. Graduate in PICYT CIDESI Querétaro Mexico in 2021. He is professor in the robotics engineering department and coordinator of the master's degree in advanced technology of Polytechnic University of Guanajuato. He has worked on projects such as robot design, evaluation of residual stresses in thermally affected zones, mechanical validation of hip prostheses, powder metallurgy, implementation of industrial robots, conversion of an internal combustion vehicle to electric and currently in the development of an electric single-seater similar to formula one. He collaborated in the installation and start-up of the laser technology laboratory for LSP applications at CIDESI. He performed simulation work of treatment LSP and has also worked with researchers from the University of Guadalajara, CIDESI and the Polytechnic University of Madrid. His research interests include advanced design mechanism, mechanical design, CAD-CAM-CAE technologies, fatigue and experimental mechanics.