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elastic modulus of 304 Stainless Steel Coating by Cold Gas Dynamic Spraying

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Journal of Iron and Steel Research International 2012年第3期19卷 73-78页

作者： HAN Wei1, MENG Xian-ming1, ZHANG Jun-bao2, ZHAO Jie1 (1. School of Material Science and Engineering, Dalian University of Technology, Dalian 116085, Liaoning, China 2. Baoshan Iron and Steel Company Limited, Baosteel Research Institute, Shanghai 201900, China) School of Material Science and Engineering Dalian University of Technology Dalian Liaoning China Baoshan Iron and Steel Company Limited Baosteel Research Institute Shanghai China

304 stainless steel coating was deposited on the IF steel substrate by cold gas dynamic spraying （CGDS）, and the elastic modulus of the 304 stainless steel coating was studied. The elastic modulus of cold sprayed 304 stain- less steel coating was measured using the three-point bend testing and the compound beam theory, and the other me- chanic parameters （such as the equivalent flexural rigidity and the moment of inertia of area） of the coatings were also calculated using this compound beam theory. It is found that the calculated results using the above methods are accu- rate and reliable. The elastic modulus value of the cold sprayed 304 stainless steel coating is 1. 179 X 105 MPa, and it is slightly lower than the 304 stainless steel plate （about 2 X 105 MPa）. It indicates that the elastic modulus of the cold sprayed coatings was quite different from the comparable bulk materials. The main reason is that the pores and other defects are existed in the coatings, and the elastic modulus of the coatings also depends on varies parameters such as the feed stock particle size, porosity, and processing parameters.

关键词： cold gas dynamic spraying 304 stainless steel coating three-point bend testing compound beam theory elastic modulus

elastic modulus Prediction of Three-dimension-4 Directional Braided C_f/SiC Composite Based on Double-scale Model

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Journal of Wuhan University of Technology(Materials Science) 2015年第3期30卷 500-508页

作者：牛序铭 SUN Zhigang KONG Chunyuan 宋迎东 Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics State Key Laboratory of Mechanics and Control Mechanical Structures College of Energy and Power Nanjing University of Aeronautics & Astronautics

Double-scale model for three-dimension-4 directional（3D-4d） braided C/SiC composites has been proposed to investigate its elastic properties. The double-scale model involves micro-scale that takes fiber/ matrix/porosity in fibers tows into consideration with unit cell which considers the 3D-4d braiding structure. Micro-optical photographs of composites have been taken to study the braided structure. Then a parameterized finite element model that reflects the structure of 3D-4d braided composites is proposed. Double-scale elastic modulus prediction model is developed to predict the elastic properties of 3D-4d braided C/SiC composites. Stiffness and eompliance-averaging method and energy method are adopted to predict the elastic properties of composites. Static-tension experiments have been conducted to investigate the elastic modulus of 3D-4d braided C/SiC composites. Finally, the effect of micro-porosity in fibers tows on the elastic modulus of 3D-4d braided C/SiC composites has been studied. According to the conclusion of this thesis, elastic modulus predicted by energy method and stiffness-averaging method both find good agreement with the experimental values, when taking the micro-porosity in fibers tows into consideration. Differences between the theoretical and experimental values become smaller.

关键词： 3D-4d braided C/SiC composites double-scale model elastic modulus energy methodstiffness and compliance-averaging method porosity ratio

elastic modulus of claystone evaluated by nano-/micro-indentation tests and meso-compression tests

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 84-91页

作者： Christophe Auvray Noémie Lafrance Danièle Bartier Université de Lorraine CNRS CREGU Lab. GeoRessources UMR 7359 Vandoeuvre-lès-Nancy F-54518 France

Toarcian claystone such as that of the Callovo-Oxfordian is a qualified multiphase material. The claystone samples tested in this study are composed of four main mineral phases: silicates(clay minerals, quartz,feldspars, micas)(z86%), sulphides(pyrite)(z3%), carbonates(calcite, dolomite)(z10%) and organic kerogen(z1%). Three sets of measurements of the modulus of deformability were compared as determined in(i) nanoindentation tests with a constant indentation depth of 2 mm,(ii) micro-indentation tests with a constant indentation depth of 20 mm, and(iii) meso-compression tests with a constant displacement of 200 mm. These three experimental methods have already been validated in earlier studies. The main objective of this study is to demonstrate the influence of the scaling effect on the modulus of deformability of the material. Different frequency distributions of the modulus of deformability were obtained at the different sample scales:(i) in nano-indentation tests, the distribution was spread between 15 GPa and 90 GPa and contained one peak at34 GPa and another at 51 GPa;(ii) in the micro-indentation tests, the distribution was spread between 25 GPa and 60 GPa and displayed peaks at 26 GPa and 37 GPa; and(iii) in the meso-compression tests, a narrow frequency distribution was obtained, ranging from 25 GPa to 50 GPa and with a maximum at around 35 GPa.

关键词： Claystone elastic modulus Scaling effect Nano-and micro-indentation Meso-compression tests Multi-scale mechanical tests

SIZE EFFECTS OF elastic modulus OF FCC METALS BASED ON THE CAUCHY-BORN RULE AND NANOPLATE MODELS

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Acta Mechanica Solida Sinica 2014年第2期27卷 111-121页

作者： Jianyun Liu Jingru Song Yueguang Wei State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

In the present research, a simple quasi-continuum model, the Cauchy-Born rule model, is used to investigate the size effects of elastic modulus for fcc metals. By considering a nanoplate model and calculating the strain energy for the nano-sized plate under tension and bending, the relationship between the elastic modulus and the plate thickness is found. Size effects of the elastic modulus are displayed by the relative differences of the elastic modulus between the nano-sized plate sample and the bulk sample. By comparing the present results with those of others, the effectiveness of the Cauchy-Born rule model in studying the size effects of material properties are shown.

关键词： quasi-continuum method Cauchy-Born rule size effect elastic modulus fcc-metal

The influence of spark plasma sintering temperatures on the microstructure,hardness,and elastic modulus of the nanocrystalline Al-xV alloys produced by high-energy ball milling

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Journal of Materials Science & Technology 2022年第27期122卷 68-76页

作者： J.Christudasjustus C.S.Witharamage Ganesh Walunj T.Borkar R.K.Gupta Department of Materials Science and Engineering North Carolina State UniversityRaleighNC 27606United States Department of Mechanical Engineering Cleveland State UniversityClevelandOH 44115United States

Al-xV alloys(x=2 at.%,5 at.%,10 at.%)with nanocrystalline structure and high solid solubility of V were produced in powder form by high-energy ball milling(HEBM).The alloy powders were consolidated by spark plasma sintering(SPS)employing a wide range of temperatures ranging from 200 to 400°*** microstructure and solid solubility of V in Al were investigated using X-ray diffraction analysis,scanning electron microscope and transmission electron *** microstructure was influenced by the SPS temperature and V content of the *** alloys exhibited high solid solubility of V–six orders of magnitude higher than that in equilibrium state and grain sizeelastic modulus,measured using nanoindentation,were significantly higher than commercial *** example,Al-V alloy produced by SPS at 200℃ exhibited a hardness of 5.21 GPa along with elastic modulus of 96.21 *** evolution of the microstructure and hardness with SPS temperatures has been discussed.

关键词： Spark plasma sintering Aluminum alloys Nanocrystalline alloys High-energy ball milling Nanoindentation Hardness elastic modulus

Size effect of the elastic modulus of rectangular nanobeams:Surface elasticity effect

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Chinese Physics B 2013年第10期22卷 424-428页

作者：姚海燕云国宏范文亮 College of Ordos Inner Mongolia University Inner Mongolia Key Laboratory of Nanoscience and Nanotechnology College of Physical Science and Technology Inner Mongolia University College of Physics and Electronic Information Inner Mongolia Normal University

The size-dependent elastic property of rectangular nanobeams （nanowires or nanoplates） induced by the surface elas- ticity effect is investigated by using a developed modified core-shell model. The effect of surface elasticity on the elastic modulus of nanobeams can be characterized by two surface related parameters, i.e., inhomogeneous degree constant and surface layer thickness. The analytical results show that the elastic modulus of the rectangular nanobeam exhibits a distinct size effect when its characteristic size reduces below 1 O0 nm. It is also found that the theoretical results calculated by a mod- ified core-shell model have more obvious advantages than those by other models （core-shell model and core-surface model） by comparing them with relevant experimental measurements and computational results, especially when the dimensions of nanostructures reduce to a few tens of nanometers.

关键词： size effects elastic modulus nanobeams surface elasticity

Whisker Orientation Function and elastic modulus of the as-cast 20% SiC_W/Mg Composite

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Rare Metals 2001年第4期20卷 270-274页

作者： Chuanhai Jiang1, Jiansheng Wu1, Mingyi Zheng2, Dezun Wan 2 1) Key Laboratory for High Temperature Materials and Tests of the Ministry of Education, Shanghai Jiaotong University. Shanghai 200030, China 2) School of Materials Science and Engineering, Harb 上海交通大学教育部高温材料及高温测试重点实验室上海 200030 哈尔滨工业大学黑龙江哈尔滨 150001

The relationship between the plane-orientation function and the space-orientation function of whiskers in whisker-reinforced metal matrix composites was analyzed theoretically. The actual orientation of whiskers in the as-cast 20%SiCw/Mg composite (SiCw content in volume fraction) were investigated, and the elastic modulus of the composite was measured with an ultrasonic velocity analyzer. Results show that there is an evident difference between the plane-orientation function and the space-orientation function of whiskers and the space-orientation function can represent the actual condition of the composite. Only by using the space-orientation function of whiskers, the difference of elastic modulus of the as-cast composite in different directions can be explained reasonably.

关键词： SiC whisker Mg composite whisker orientation elastic modulus

Effects of thickness and elastic modulus on stress condition of fatigue-resistant coating under rolling contact

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Journal of Central South University 2010年第5期17卷 899-905页

作者：朴钟宇徐滨士王海斗濮春欢 School of Mechanical Engineering Yanshan University National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering

The distribution and magnitude of surface substrates were investigated by finite element method and subsurface stresses of the （FEM）. The models of coating single-layer sprayed-coatings on monolithic configurations with different thicknesses and elastic modulus ratios of coating to substrate were introduced, and the effects of thickness and elastic modulus ratio on the stresses were addressed. The calculation results show that the coating/substrate interface shear stress obviously decreases with increasing coating thickness, due to the location of the maximum shear stress moving away from the coating/substrate interface. At the same time, the magnitude of von Mises stress also declines in the case of thicker coatings. However, the high elastic modulus ratio results in extremely high maximum shear stress and the severe discontinuity of the von Mises stress curves, which leads to the intensive stress concentration on the coating/substrate interface. So the coating configurations with the larger coating thickness and lower difference of elastic modulus between coating and substrate exhibit excellent resistant performance of rolling contact fatigue （RCF）.

关键词： sprayed-coating thickness elastic modulus maximum stress von Mises stress finite element method

How believable are published laboratory data?A deeper look into system-compliance and elastic modulus

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第3期13卷 487-499页

作者： Aly Abdelaziz Giovanni Grasselli Department of Civil and Mineral Engineering University of Toronto35 St.George StreetTorontoOntarioM5S 1A4Canada

elastic modulus(E)interpretation is debatable with limited literature detailing the impact of *** address this impact,a comprehensive testing schedule using an aluminium 6061(Al)sample is carried out on several systems under various test *** is chosen as it is extruded and adheres to well defined shape tolerances and elastic properties.A robust method,using the Savitzky-Golay filter,is introduced to identify significant slope changes in the stressestrain *** the load in the test system is well defined,the recorded deformation is corrected to the expected value of Al resulting in a system-compliance *** results across the testing systems and test setups showed significant variance,with the recorded E always lower than the anticipated *** number of components within the system over which the deformation is measured had the most significant impact,lowering the expected E by up to 50%.Additionally,the system-compliance factor is inconsistent across different systems and ***,it is evidently proved that each setup must be separately evaluated for its system-compliance and that no single value exists across systems and *** findings are then projected onto a series of uniaxial compressive strength(UCS)tests carried out on Stanstead granite(SS GR)*** corrected Et50 and Eavg values for system-compliance of the samples are within1%for each system as opposed to being50%*** findings conclude that it is deemed necessary and of utmost importance that the deformation be corrected to accommodate the systemcompliance to obtain reliable results.

关键词： System-compliance elastic modulus Stressestrain Compressive strength of rock