Publications related to Laser peening

Strain engineering and strain measurement by spring tethers on suspended epitaxial GaN-on-Si photonic crystal devices

Suspended epitaxial gallium nitride (GaN) on silicon (Si) photonic crystal devices suffer from large residual tensile strain, especially for long waveguides, because fine structures tend to crack due to large stress. By introducing spring-like tethers, des ...

Iop Publishing Ltd2024

Database of Residual Stress Measurements on Hot-rolled Wide Flange Steel Cross Sections

Dimitrios Lignos, Albano António De Abreu E Presa De Castro E Sousa, Andronikos Skiadopoulos

Data_info.csv: Database of 'Residual Stress Measurements on Hot-rolled Wide Flange Steel Cross Sections' including cross-sectional and material characteristics as well as information relevant to ploting the residual stress distributions. Distributions.zip: ...

Zenodo2023

Proposed residual stress model for hot‐rolled wide flange steel cross sections

Dimitrios Lignos, Albano António De Abreu E Presa De Castro E Sousa, Andronikos Skiadopoulos

Residual stresses in hot-rolled wide flange steel cross sections may lead to premature yielding, accelerated corrosion and brittle fracture of steel members. The above phenomena lead to a loss of a steel member's stiffness and resistance under mechanical l ...

Ernst & Sohn2023

Nanomechanical Modeling of the Bending Response of Silicon Nanowires

Yusuf Leblebici, Zuhal Tasdemir, Mohammad Nasr Esfahani, Mustafa Yilmaz

Understanding the mechanical behavior of silicon nanowiresis essentialfor the implementation of advanced nanoscale devices. Although bendingtests are predominantly used for this purpose, their findings shouldbe properly interpreted through modeling. Variou ...

AMER CHEMICAL SOC2023

FEM of stress partition during compression of WC-10 wt.% Co with realistic 3D morphology

Daniele Mari, Lucas Eric Jacques Degeneve

A Finite Element Model is developed to represent the mechanical behavior of WC-10 wt.% Co in compression tests. In this research, realistic three-dimensional model is obtained by slicing a sample by Focused Ion Beam and reconstituting it, resulting in two ...

ELSEVIER SCI LTD2022

A parametric neutron Bragg edge imaging study of additively manufactured samples treated by laser shock peening

Roland Logé, Christian Leinenbach, Nikola Kalentics, Markus Strobl

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 conventiona ...

Nature Portfolio2021

Laser treatment systems and methods for in-situ laser shock peening (lsp) treatment of parts during production thereof by a selective laser sintering or melting (sls/slm) process, and additive manufacturing systems and methods implementing the same

Roland Logé, Nikola Kalentics

There is described, in accordance with a first aspect of the invention, a laser treatment system and method for, in particular, imparting beneficial residual stresses into a desired part (P) during production thereof by a Selective Laser Sintering or Melti ...

2021

Laser powder-bed fusion of metallic alloys with enhanced microstructures and properties

Navid Sohrabi

Laser powder-bed fusion (LPBF) is an additive manufacturing (AM) process that uses a laser to selectively melt a powder bed. This process can build dense samples with complicated geometries from a wide variety of metallic alloys. In this thesis, LPBF of al ...

EPFL2021

Morphomechanical Model Of The Torsional C-Looping In The Embryonic Heart

Alfio Quarteroni

Before septation processes shape its four chambers, the embryonic heart is a straight tube that spontaneously bends and twists breaking the left-right symmetry. In particular, the heart tube is subjected to a cell remodeling inducing ventral bending and de ...

SIAM PUBLICATIONS2021

Investigation of residual stresses in planar dissimilar magnetic pulse welds by neutron diffraction

Jean-Marie Drezet

Residual stresses are investigated for the first time in a dissimilar AA1050-DP450 steel magnetic pulse weld using neutron diffraction. Close to the joint interface, tensile residual stresses are observed in the Al sheet and compressive residual stresses a ...

ELSEVIER SCI LTD2021

Fatigue Performance of an Additively Manufactured Zr-Based Bulk Metallic Glass and the Effect of Post-Processing

Roland Logé, Jamasp Jhabvala, Baptiste Thomas Jean Rouxel, Annapaola Parrilli, Navid Sohrabi, Milad Hamidi Nasab

Fatigue is the most common cause of failure of mechanical parts in engineering applications. In the current work, we investigate the fatigue life of a bulk metallic (BMG) glass fabricated via additive manufacturing. Specimens fabricated via laser powder-be ...

MDPI2021

Post-tensioning of glass beams: Analytical determination of the allowable pre-load

Alain Nussbaumer, Pieter Christian Louter, Jagoda Cupac

The effectiveness of post-tensioning in enhancing the fracture resistance of glass beams depends on the level of compressive pre-stress introduced at the glass edge surface that will in service be exposed to tensile stresses induced by bending. Maximum pre ...

2021

Influence of Hf on the heat treatment response of additively manufactured Ni-base superalloy CM247LC

Roland Logé, Jamasp Jhabvala, Christian Leinenbach, Hossein Ghasemi Tabasi, Shreyas Sanjay Joglekar

The influence of Hf on the heat treatment response of a Laser Powder Bed Fusion (L-PBF) fabricated Ni-base superalloy was investigated. A Hf-free version of CM247LC, CM247LC NHf, and CM247LC (similar to 1.4 wt% Hf) were subjected to identical thermal treat ...

ELSEVIER SCIENCE INC2021

Role of mean stress on fatigue behavior of a 316L austenitic stainless steel in LWR and air environments

Philippe Spätig, Hans-Peter Seifert

Mean stress effects on fatigue life of a stainless steel in air and boiling water reactor (BWR) environments were evaluated by load-controlled tests. In stress-life, non-zero mean stresses increase life in low cycle fatigue regime in both environments and ...

ELSEVIER SCI LTD2021

Investigating the cracking of plastered stone masonry walls under shear–compression loading

Katrin Beyer, Amir Rezaie, Michele Godio

Cracks are the most important source of information about the damage that occurs to unreinforced masonry piers under seismic actions. To predict the structural state of unreinforced masonry piers after an earthquake, research models have been developed to ...

2021

Investigation of the effect of Laser Shock Peening in Additively Manufactured samples through Bragg Edge Neutron Imaging

Roland Logé, Markus Strobl, Nikola Kalentics

Additive manufacturing is a promising and rapidly rising technology in metal processing. However, besides a number of key advantages the constitution of a part through a complex thermo-mechanical process implies also some severe issues with the potential o ...

ELSEVIER2020

3D laser shock peening - A new method for improving fatigue properties of selective laser melted parts

Roland Logé, Christian Leinenbach, Nikola Kalentics, Manuel Ortega Varela De Seijas

Although Selective Laser Melting (SLM) currently revolutionizes the way parts are being manufactured, certain process inherent limitations such as accumulation of residual stresses and increased porosity content can lead to a decrease in fatigue life of pr ...

ELSEVIER2020

First observation of spalling in tantalum at high temperatures induced by high energy proton beam impacts

Philippe Spätig, Elvis Fornasiere, Marco Calviani

Spalling in tantalum has been observed in an experiment aiming at testing an antiproton production target prototype at CERN’s HiRadMat Facility. The experiment consisted in impacting 47 intense and high-energy proton beams onto a target equipped with ten c ...

2020

Fatigue properties of as-welded and post-weld-treated high-strength steel joints: The influence of constant and variable amplitude loads

Alain Nussbaumer, Halid Can Yildirim, Heikki Tapani Remes

In HSS welded structures, HFMI allows fatigue strength improvement factors by inducing compressive residual stresses, cold-worked surface region and modifying the weld toe shape. According to the literature, the factors are proposed based on failures at CA ...

2020

Fretting-corrosion behavior of electroless Ni-P/Ni-P-TiO2 coatings obtained on AZ91D magnesium alloy by a chromium-free process

Stefano Mischler, Angela Bermudez Castañeda

Ni-P electroless coatings are widely applied for protection of magnesium alloys and other materials due to the low energy consumption of the process and high resistance to corrosion and wear, properties that can be improved with the incorporation of partic ...

ELSEVIER2020