Advanced mechanical surface enhancement techniques have been used successfully to increase the fatigue life of metallic components. These impart deep compressive residual stresses into component counter potentially damage-inducing tensile generated under service loading. Laser shock peening (LSP) is an advanced technique predominantly in aircraft industry. To reduce costs and make available on a large-scale basis for industrial applications, simulation LSP process required. Accurate...

Finger strength is a key determinant of climbing performance, yet the optimal method for reliable assessment remains unsettled. This study evaluated reliability and validity finger assessments across four positions: seated standing with bent straight arms. Twenty-six intermediate-to-elite climbers completed climbing-specific isometric pull-down test on two occasions, 48-96 hours apart. Average peak force outputs from mean three attempts best single attempt were analyzed. Tests performed arms...

Laser shock peening (LSP) as a surface treatment technique can improve the fatigue life and corrosion resistance of metallic materials by introducing significant compressive residual stresses near surface. However, LSP-induced are known to be dependent on multitude factors, such laser process variables (spot size, pulse width energy), component geometry, material properties sequence. In this study, an intelligent system based machine learning was developed that predict stress distribution...

Laser shock peening has become a commonly applied industrial surface treatment, particularly for high-strength steel and titanium components. Effective application to aluminum alloys, especially in the thin sections common aerospace structures, proved more challenging. Previous work shown that some conditions can introduce at-surface tensile residual stress Al sections. In this study, we employ finite element modeling identify cause occur, show how these adverse effects be mitigated through...

Purpose The purpose of this paper is to develop and implement a structural fatigue life estimation framework that includes laser‐peened (LP) residual stresses then experimentally validates these estimations. Design/methodology/approach A three‐dimensional finite element analysis an Al 7075‐O three‐point bending coupon being LP was created used estimate the when loaded. Fatigue tests were conducted validate Findings developed for LP‐processed coupons yielded estimates with goodness‐of‐fit...

Finite element modeling can be a powerful tool for predicting residual stresses induced by laser peening; however the sign and magnitude of stress predictions depend strongly on how material model captures high strain rate response. Although Johnson-Cook formulation is often employed, its suitability phenomena at very rates has not been rigorously evaluated. In this paper, we address effectiveness model, with parameters developed from lower data (∼103 s–1), to capture higher response (∼105...

A method is introduced for efficient reliability-based design of laser peening (LP) surface treatment to extend fatigue life metal components. The includes nonparametric probability density estimation, surrogate modeling using a new finite element (FE or FEA) approach, and reliability analysis with correlated random variables (RVs). Efficient LP simulation achieved via technique termed single explicit time-dependent damping (SEATD), which reduces times by factor 6. example study three-point...

Estimation of black-box functions often requires evaluating an extensive number expensive noisy points. Learning algorithms can actively compare the similarity between evaluated and unevaluated points to determine most informative subsequent for efficient estimation in a sequential procedure. In this paper, we propose active learning methodology based on integration Laplacian regularization - Cohn (ALC) measure identification using Gaussian processes. We two simple greedy search optimization...

In the laser shock peening (LSP) process, favorable residual stresses are induced on a surface to improve fatigue and fretting properties of that part metal surface. literature, experimental-based advances have been attempted understand derive maximum benefits from process demonstrate technology. However, time consuming expensive experiments, limited simulations simple geometries not sufficient for optimal LSP design. A comprehensive simulation procedure is required can be employed in...

Laser peening (LP) has shown to be a viable method by which the fatigue life of metallic components can extended. Although current commercial implementation LP techniques not developed much beyond trial-and-error methodology implement process, researchers at several institutions have examined various parameters that affect residual stress fields induced LP, using Finite Element Analysis (FEA) and semi-empirical eigenstrain methods. This research is preliminary investigation potentially...

Abstract There are several sequential and adaptive strategies designed to reduce the number of experiments in response surface methodology (RSM). However, most existing methods sensitive existence possible outliers. In this paper, we propose an active learning based on fundamental idea adding a Laplacian penalty D‐optimal design integrate that with robust regression look for informative settings be measured, while reducing influence To leverage intrinsic geometry factor highly nonlinear...

Laser shock peening (LSP) is a method of work hardening used to improve fatigue life. Finite element (FE) modeling LSP lacks confidence, primarily due the unknown shape acting pressure impulse in both time and space. This developed tested an integrated FEM/optimization model determine 'best fit' based on easy measure surface displacement residual stress data from single burst. Isight optimization software was conjunction with Abaqus FEM, MATLAB, Excel utilize Hooke-Jeeves algorithm for...