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Enhancing the surface hardness and roughness of engine blades using the shot peening process

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International Journal of Minerals,Metallurgy and Materials 2019年第8期26卷 999-1004页

作者： Mohammad A.Omari Hamzah M.Mousa Faris M.AL-Oqla Mohammad Aljarrah Department of Mechanical Engineering Jordan University of Science and TechnologyIrbid 22110Jordan Department of Mechanical Engineering The Hashemite UniversityZarqa 13133Jordan Department of Industrial Engineering The Hashemite UniversityZarqa 13133Jordan

The effects of shot peening on the mechanical properties of steel 1070 were studied to enhance the material’s properties and surface *** this study,pressure and exposure time were the main parameters governing surface hardness and surface *** optimal time duration and pressure were determined after several experimental *** in hardness and surface roughness were monitored as the pressure of the shot and the exposure time were ***,the microstructure was evaluated by scanning electron microscopy(SEM)and the images were enhanced by image processing techniques to evaluate the surface *** charts were constructed to estimate the effects of pressure and time on both surface hardness and surface *** novelty of this study is the concentration on engine blades which are frequently used in aircrafts to determine the optimal time–pressure combination for shot peening to achieve suitable mechanical and surface *** results show that shot peening pressure(up to 482.6 kPa for 7 min)has positive effect on enhancing the surface and mechanical properties for steel 1070 blades;however,an increase in either pressure or time above that level adversely affected both surface hardness and surface roughness.

关键词： shot peening roughness hardness engine blades scanning electron microscopy

Effects of shot peening and laser remelting on oxygen-permeation treatment of titanium alloy

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中国有色金属学会会刊：英文版 2004年第z1期14卷 268-273页

作者： MA Hong-yan WANG Mao-cai WEI Zheng XIN Gong-chun State Key Laboratory for Corrosion and Protection Institute of Metal Research Graduate School of Chinese Academy of Sciences Beijing 100030 China State Key Laboratory for Corrosion and Protection Institute of Metal Research Graduate School of Chinese Academy of Sciences Beijing 100030 China Shenyang Liming Aero-engine Group Corporation Shenyang 110043 China Shenyang Liming Aero-engine Group Corporation Shenyang 110043 China

The influence of surface pre-treatments, shot-peening (SP) and laser remelting (LR), on oxygen permeation behaviors of titanium alloy TC11 was investigated. Optical microscope, SEM with EDAX, XRD, and microhardness tester were employed to characterize the microstructure, composition and hardness of this alloy. The results show that the surface roughness is increased by shot-peening, and the microstructure with fine-grain can be obtained by LR pre-treatment. The pre-treated samples were oxygen-permeated at (810± 10) ℃ for 10 h in atmospheric air. The outer layer consists essentially of TiO2, trace Ti2 N, Ti3Al and Ti3AlN for the SP pre-treatment and thin oxygen solution layer is found in the subsurface layer. As for LR pre-treatment, the outer layer consists mainly of TiO2 and small amounts of TiO, and the inner layer consists of alpha crystals, rich in interstitial atoms. Samples by LR pre-treatment has thicker hardened layer with higher hardness values in comparison with SP pre-treated *** boost diffusion of oxygen and hardening mechanisms were discussed based on the experimental results.

关键词： shot peening laser remelting oxygen-permeation titanium solution

Effect of shot peening on microstructure,nanocrystallization and microhardness of Ti-10V-2Fe-3Al alloy surface

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Journal of Iron and Steel Research International 2019年第1期26卷 52-58页

作者： Hai-zhong Zheng Sheng-hua Guo Qin-hao Luo Xiao-yong Shu Gui-fa Li National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology Nanchang Hangkong UniversityNanchang 330063JiangxiChina

Severe plastic deformation of Ti-10V-2Fe-3Al alloy in the surface region was caused by shot peening at air pressure of 0.6 MPa with processing time ranging from 1 to 45 *** results showed that the thickness of surface deformation layer was proportio nal to the processing time,the microhardness of the shot-peened surface in creased from 280 to 385 HV,and the depth of highly hardening layers arrived at 200μ*** was worth noting that a grain size gradient from nanocrystalline on the surface toward coarse grain in the matrix was obtained during the shot peening process and the minimum grain size in the top surface after shot peening was about 100-200 nm.

关键词： Ti-10V-2Fe-3Al alloy shot peening treatment Surface nanocrystallization Martensitic transformation Microhardness

Effects of interface bound states on the shot noise in normal metal–low-dimensional Rashba semiconductor tunnel junctions with induced s-wave pairing potential

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Chinese Physics B 2019年第5期28卷 268-275页

作者： Wen-Xiang Chen Rui-Qiang Wang Liang-Bin Hu Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication Engineering South China Normal University

We consider the effects of interface bound states on the electrical shot noise in tunnel junctions formed between normal metals and one-dimensional(1 D) or two-dimensional(2 D) Rashba semiconductors with proximity-induced s-wave pairing potential. We investigate how the shot noise properties vary as the interface bound state is evolved from a non-zero energy bound state to a zero-energy bound state. We show that in both 1 D and 2 D tunnel junctions, the ratio of the noise power to the charge current in the vicinity of zero bias voltage may be enhanced significantly due to the induction of the midgap interface bound state. But as the interface bound state evolves from a non-zero energy bound state to a zero-energy bound state, this ratio tends to vanish completely at zero bias voltage in 1 D tunnel junctions, while in 2 D tunnel junctions it decreases smoothly to the usual classical Schottky value for the normal state. Some other important aspects of the shot noise properties in such tunnel junctions are also clarified.

关键词： interface bound state tunnel junction shot noise

Surface nanostructures in commercial pure Ti induced by high energy shot peening

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中国有色金属学会会刊：英文版 2004年第z1期14卷 215-218页

作者： CHEN Chun-huan REN Rui-ming ZHAO Xiu-juan ZHANG Yu-jun School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China School of Materials Science and Engineering Dalian Jiaotong University Dalian 116028 China

The high-energy shot peening (HESP) technique was used to obtain the surface nanocrystalline microstructure for a hcp metal titanium. XRD, SEM and TEM were applied to characterize the microstructure of the surface layer. Large amount of the deformation twins in the surface layer were observed by SEM in the specimens after HESP treatment in a shot-time, and the number of deformation twins both in a single plane and in intersecting planes increases with HESP time, until the twin character disappears completely in the top surface layer, which means that the severe plastic deformation(SPD) occurs on the surface. The XRD analysis results show that after HESP treatmen for 30 - 60 min the surface grain size decreases to nanoscale. According to the TEM images and corresponding diffraction patterns from SPD areas of the 120 min-treatment specimen, the measured grain size near the surface is about 20 - 30 nm. The grain size in deformation layer increases with the depth from the surface, and the nanostructured layer is about 20 μm in depth. Therefore, the surface nanocrystalline and a gradient microstructure from the surface to the matrix are obtained, which results in the micro-hardness decreasing from surface to the matrix gradually.

关键词： surface nanocrystallization shot peening commercial pure Ti

Influence of shot Peening Treatment on the Fatigue and Corrosion Resisting Properties of 2Cr13 Stainless Steel

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稀有金属材料与工程 2012年第S1期41卷 236-238页

作者： Liu Mingxia Zhang Haicun Liu Daoxin Han Zengfu Zhi Jinhua Guo Wenyong Zhou Yafeng Xian Shaangu Power CO LTD Xian 710075 Peoples R China NW Polytech Univ Xian 710072 Peoples R China

In the present paper,shot peening treatments were used to strengthen the steel surface,and the influence on the fatigue and corrosion resisting properties of 2Cr13 stainless steel was *** residual stress and the surface roughness were investigated by XRD and *** characteristics of fatigue and corrosion resistance have also been analyzed by bending fatigue and salt spray *** result reveals that the fatigue limit of the samples is improved dramatically with the increasing of the peening strength by 7.5%.Meanwhile,the peenging angle has no evident influence on the fatigue *** with the untreated samples,the acid corrosion weight loss of the samples after the shot peening treatment is decreased almost by 90%.From the above experimental results proper shot peening would improve not only the fatigue property but also the corrosion resistance of 2Cr13-typed stainless steel.

关键词： stainless steel shot peening fatigue limit corrosion resistance

Numerical Simulation of Derusting Treatment of Steel Parts By shot Blast

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Computer Modeling in Engineering & Sciences 2019年第7期120卷 157-175页

作者： Zhe Li Fan Yang Yaping Liu Yukui Gao School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

In this paper,we investigated the shot blast treatment for derusting application through finite element(FE)simulations with a large number of random *** element deletion technique based on dynamic failure criteria was used to model the removal of *** cohesive surface model with damage evolution was used to characterize the decohesion of the rust/substrate *** effects of various processing and material parameters on the derusting effectiveness were *** results show that the rate of derusting mainly depends on the shot size,velocity and impinging angle,with little relevance to the rust *** spalling of the rust fragments resulted from the decohesion of the rust/substrate interface were observed,especially during the later stage of the ***,the residual stress and the surface roughness was also investigated and the beneficial effects of shot blast treatment in terms of these aspects were highlighted.

关键词： shot blast rust removal cohesive surface finite element

A shot Clustering Based Algorithm for Scene Segmentation

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China Communications 2007年第4期4卷 61-65页

作者： Wang Xuejun Wang Shigang Chen Hexin Jilin Univ Sch Telecommun Engn Changchun 130012 Peoples R China

A scene segmentation method utilizing both visual features and motion features of video is presented in this *** only the visual similarity but also the motion consistency of shots within a scene is considered in clustering shots into *** addition,a method to merge the over-segmented scenes is presented *** the experimental results show the effectiveness of the proposed algorithms.

关键词： scene segmentation shot similarity shot clustering

Experimental Research on Laser shot Peening to Form Aluminum Alloy

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武汉理工大学学报 2006年第S3期28卷 837-840页

作者： ZHANG Xingquan ZHANG Yongkang GU Yongyu ZHOU Jianzhong YANG Chaojun School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013,China, School of Mechanical Engineering Jiangsu UniversityZhenjiang 212013China

Laser shot peening forming is a novel technology,which employs residual stress induced by intense laser to shape precisely the *** this paper,the aeronautic aluminum alloy LY12CZ was selected as an object to research experimentally the magnitude of deformation versus numbers of laser shot peening,and surface quality in laser shot zone was also *** specimen was impacted along its centerline by the high-power,short-duration pulses *** experimental results show that the arc height and hardness becomes greater with numbers of shot peening increasing and eventually arrives to saturated state,and sur- face roughness after laser shot peening decreases slightly and dislocation density increases greatly,which indicates that the laser shot peening is a technique combining laser shock processing and metal forming.

关键词： laser shot peening deformation hardness roughness microstructure