Results 41 to 50 of about 11,983 (293)

Prediction of Surface Topography Parameters in Direct Laser Interference Patterning of Stainless Steel Using Infrared Monitoring and Convolutional Neural Networks

Advanced Engineering Materials, EarlyView.
This study presents an infrared monitoring approach for direct laser interference patterning (DLIP) combined with a convolutional neural network (CNN). Thermal emission data captured during structuring are used to predict surface topography parameters.
Lukas Olawsky, Marcelo Sallese, Leander Kläber, Clemens Kuhn, Keming Du, Andrés Fabián Lasagni   +5 more
wiley   +1 more source

Thermomechanical Fatigue and Creep–Fatigue Interaction of Inconel 718 Additively Manufactured by Laser Beam Powder Bed Fusion

Advanced Engineering Materials, EarlyView.
Thermomechanical fatigue tests of laser beam powder bed fusion (PBF‐LB) Inconel 718 show that the additively manufactured material reaches almost the lifetimes of conventionally‐rolled material under no‐dwell conditions. Introducing dwell times at the maximum temperature markedly reduces the lifetimes due to pronounced grain boundary sliding associated
Stefan Guth, Tomáš Babinský, Jan Lars Riedel, Wen Hao Kan, Aijun Huang, Martin Heilmaier, Ivo Šulák   +6 more
wiley   +1 more source

Simultaneous realization of time and carrier-envelope phase synchronization for an ultra-intense few-cycle laser pulse coherent combining system

High Power Laser Science and Engineering
Coherent combining of several low-energy few-cycle beams offers a reliable and feasible approach to producing few-cycle laser pulses with energies exceeding the multi-joule level. However, time synchronization and carrier-envelope phase difference (ΔCEP)
Guoli Zhang, Xiao Liang, Hao Xue, Xinglong Xie, Ping Zhu, Fucai Ding, Meizhi Sun, Linjun Li, Rashid Ul Haq, Ailin Guo, Xiangbing Zhu, Jianqiang Zhu   +11 more
doaj   +1 more source

Time‐Dependent Oxidation and Scale Evolution of a Wrought Co/Ni‐Based Superalloy

Advanced Engineering Materials, EarlyView.
This study shows how a new wrought Co/Ni‐based superalloy resists oxidation at 800 ∘$^\circ$C. The oxide scale changes from rough, fast‐growing spinel to a dense, protective chromia–alumina layer. Atom probe analysis reveals tiny refractory‐rich bubbles at the interface that mark the transition to long‐term, diffusion‐controlled protection ...
Cameron Crabb, Zachary T. Kloenne, Samuel R. Rogers, Chi Hang Dominik Kwok, Mark C. Hardy, Michele S. Conroy, David Dye   +6 more
wiley   +1 more source

Coherent polarization shift keying modulated free space optical links over a Gamma-Gamma turbulence channel [PDF]

, 2011
Problem statement: The optical signal propagating through the Free Space Optical (FSO) channel suffers from irradiance and phase fluctuations caused by the atmospheric turbulence, which results in Bit Error Rate (BER) performance degradation ...
Ghassemlooy, Zabih, Popoola, Wasiu Oyewole, Popoola, Wasiu O., Tang, Xuan, Rajbhandari, Sujan, Lee, Chung Ghiu, Ghassemlooy , Zabih, Lee , Chung Ghiu   +7 more
core   +1 more source

Mismatch analysis of all-fiber coherent beam combiners based on the self-imaging effect

High Power Laser Science and Engineering
All-fiber coherent beam combiners based on the self-imaging effect can achieve a near-perfect single laser beam, which can provide a promising way to overcome the power limitation of a single-fiber laser.
Yuefang Yan, Yu Liu, Haoyu Zhang, Yuwei Li, Chao Guo, Qiang Shu, Wenhui Huang, Feng Jing, Rumao Tao   +8 more
doaj   +1 more source

Karl Popper and the Mechanisms of Hydrogen Embrittlement

Advanced Engineering Materials, EarlyView.
Representation of the beginning of loss of ductility rather than embrittlement. Small concentrations of hydrogen in a diffusible form within iron are well‐established to harm the mechanical integrity of steels. There are theories that attempt to explain the pernicious role of hydrogen.
H. K. D. H. Bhadeshia
wiley   +1 more source

A Metasurface Beam Combiner Based on the Control of Angular Response

Photonics, 2021
Beam combiners are widely used in various optical applications including optical communication and smart detection, which spatially overlap multiple input beams and integrate a output beam with higher intensity, multiple wavelengths, coherent phase, etc.
Zhihao Liu, Weibin Feng, Yong Long, Songming Guo, Haowen Liang, Zhiren Qiu, Xiao Fu, Juntao Li   +7 more
doaj   +1 more source

Understanding the Stochastic Nature of Process Parameter Development of Blown Powder Laser Beam Directed Energy Deposition Additive Manufacturing of Pure Molybdenum

Advanced Engineering Materials, EarlyView.
Identified through the use of statistical design of experiments and metallographic investigation, this study exposes the stochastic origins of intergranular cracks in blown powder laser beam directed energy deposition additive manufacturing of pure molybdenum. It further demonstrates a successful crack mitigation approach with direct correlation to the
Nathaniel J. Lies, Daniel E. Driemeyer, Aaron P. Stebner   +2 more
wiley   +1 more source

Coherent beam combining of high power tapered (poster)

, 2017
International audienceWe describe the coherent beam combining of three high-power tapered laser amplifiers seeded by a DFB laser at λ = 976 nm, and demonstrate a combined power of 12.9 W in a close to diffraction-limit beam at a combining efficiency of >
Moron, Frédéric, Blume, G, M., Winterfeldt, Decker, J, Crump, Paul, Hanna, Marc, Georges, Patrick, Albrodt, Philipp, Lucas-Leclin, Gaëlle   +8 more
core   +3 more sources