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Methods for Detection of Subsurface Damage:A Review

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 23-36页

作者： Jing-fei Yin Qian Bai Bi Zhang Key Laboratory for Precision and Non-traditional Machining of Ministry of Education Dalian University of Technology Department of Mechanical and Energy Engineering South University of Science and Technology

Subsurface damage is easily induced in machining of hard and brittle materials because of their particular mechani?cal and physical properties. It is detrimental to the strength,performance and lifetime of a machined part. To manu?facture a high quality part,it is necessary to detect and remove the machining induced subsurface damage by the subsequent processes. However,subsurface damage is often covered with a smearing layer generated in a machining process,it is rather di cult to directly observe and detect by optical microscopy. An e cient detection of subsur?face damage directly leads to quality improvement and time saving for machining of hard and brittle materials. This paper presents a review of the methods for detection of subsurface damage,both destructive and non?destructive. Although more reliable,destructive methods are typically time?consuming and confined to local damage infor?mation. Non?destructive methods usually su er from uncertainty factors,but may provide global information on subsurface damage distribution. These methods are promising because they can provide a capacity of rapid scan and detection of subsurface damage in spatial distribution.

关键词： Subsurface damage Hard and brittle material Taper polishing Measurement laser scattering

Speckle intensity images of target based on Monte Carlo method

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Chinese Physics B 2014年第3期23卷 545-549页

作者：武颖丽吴振森 Xidian University School of Science

Speckle intensity in the detector plane is deduced in the free-space optical system and imaging system based on Van Cittert-Zemike theorem. The speckle intensity images of plane target and conical target are obtained by using the Monte Carlo method and measured experimentally. The results show that when the range extent of target is smaller, the speckle size along the same direction become longer, and the speckle size increase with increasing incident light wavelengths. The speckle size increases and the speckle intensity images of target is closer to the actual object when the aperture scale augments. These findings are useful to access the target information by speckle in laser radar systems.

关键词： laser scattering Monte Carlo method speckle intensity images

Elastic rescattering photoelectron distributions entering the relativistic regime

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Chinese Optics Letters 2015年第7期13卷 9-13页

作者： Sui S.Luo Pat Grugan Siyu Luo Barry C.Walker Physics and Astronomy Department University of Delaware

We report photoelectron energy spectra and angular distributions for ionization with elastic scattering in ultra- strong laser fields. Noble gas species with Hartree-Fock scattering potentials show a reduction in elastic rescat- tering with the increasing energy of ultrastrong fields and when the Lorentz deflection of the photoelectron exceeds its wave function spread. The relativistic extension of a three-step recollision model is well-suited to the ultrastrong intensity regime （〉10^17 W/cm2） that lies between traditional strong fields and extreme relativistic interactions.

关键词： Elastic scattering Electric fields laser scattering Magnetic fields scattering Strong field physics

On variation of surface topography and robust product performance

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Instrumentation 2014年第1期1卷 1-7页

作者： B.-G.Rosen L.Baath Z.Dimkovski Halmstad University Functional Surface Research GroupBox 823SE-30118HalmstadSweden Chalmers University of Technology Department of Materials and Manufacturing TechnologyGoteborgSweden Key Lab of Modern Measurement and Control Technology Beijing Information Science&Technology UniversityBeijingChina.

The customer's demands for higher quality,faster delivery times and reduction of cost,give evidence for the need to develop new technologies or enhance existing technologies combined with research *** automotive industry's capability to develop new products in a shorter time is constantly *** and die creation is a major part of the product creation for many industrial products and in particular for the automotive *** higher product requirements on reduced weight,better safety,and lower emissions have meant that a larger number of automotive body parts must be made in advanced high strength *** functionality of surface textures and engineered tailor made component surfaces is one enabling technology for industry to increase compete ability by improved component function and reduced friction ***,material properties'variation,un-evenly spread wear,unknown manufacturing process variations,the“human factor”,faulty metrology procedures…All factors interact to increase the problems of utilizing surface texturing on the micro metre level as a competitive tool for *** variation of the micro topography created by industrial machining processes tends to reduce the impact of the usage of improved engineered surfaces on critical components.A proposal of a strategy for metrology using"intelligent"sampling techniques comprising of regionalization of the functional area and designed sampling patterns is *** efficiently make use of efficient sampling,an example of a recently developed optical scattering light in-line metrology of high precision surfaces is discussed as a tool to enable efficient control of machine tools in *** steps discussed include developing of control loops for implementation in CNC controllers to efficiently make use of the"smart"surface texture characterisation data from the developed in-line surface texture sensors.

关键词： surface roughness uncertainty in-line metrology laser scattering coherence scanning interferometer