检索结果-南通市图书馆

Influence of La2O3 addition on nano indentation hardness and residual stress of Stellite 6 coating prepared by plasma cladding

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2018年第8期36卷 873-878页

作者： Yongchao Fang Xiufang Cui Zhaobing Cai Chang Wang Guo Jin Institute of Surface/Interface Science and Technology Key Laboratory of Superlight Material and Surface Technology of Ministry of EducationCollege of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China

One of the problems limiting the application of Stellite 6 coating is the residual stress resulting in cracks in the coating easily. In order to reduce the residual stress and increase the nano-indentation hardness,La2 O3 was added to Stellite 6 coating in this study, and the influence on the microstructure, nano indentation hardness and residual stress of the coatings were investigated by scanning electron microscopy（SEM） with energy dispersive spectrum（EDS）, X-ray diffraction（XRD） and nano-indentation tester. Results indicate that the addition of La2 O3 leads to the phenomenon that the dendrite is partly transformed into the equiaxed grain, which results in the grain refinement. The nano-indentation hardness of coatings is improved, which is attributed to the fine-grain strengthening and dispersion strengthening effect of La2 O3. With the addition of La2 O3, the residual stress in coatings is decreased significantly. Especially, when the content of La2 O3 is 0.8 wt%, the nano indentation hardness increases by 1.31 times and residual stress decreases to 20 percent, compared with coating without La2 O3.

关键词： plasma cladding La2O3/Stellite 6 composite coating Microstructure Nano-hardness Residual stress Rare earths

Effects of process parameters and annealing on microstructure and properties of CoCrFeMnNi high-entropy alloy coating prepared by plasma cladding

在线全文

学校读者我要写书评

暂无评论

China Foundry 2023年第6期20卷 491-502页

作者： Shi-yong Wei Chao-min Wang Wen-yi Peng Ru-kai Luo Yun Chen Zhen-zhen Wan Yin Jin Institute of Applied Physics Jiangxi Academy of SciencesNanchang 330090China Materials Science and Engineering School Nanchang UniversityNanchang 330029China

plasma cladding was used to prepare a CoCrFeMnNi high-entropy alloy(HEA)coating under different *** process parameters were optimized using an orthogonal experiment design based on surface morphology quality characteristics,dilution rate,and *** optimal process parameters were determined through range and variance analysis to be a cladding current of 70 A,a cladding speed of 7 cm·min^(-1),and a powder gas flow rate of 8 L·s^(-1).During the optimized experiments,both the cladded and annealed CoCrFeMnNi HEA coatings exhibit some pores,micro-voids,and a small amount of ***,the aggregation in the annealed coating is more dispersed than that in the cladded *** cladded CoCrFeMnNi HEA coating consists of simple FCC phases,while a new Cr-rich phase precipitates from the FCC matrix after annealing the coating at a temperature range of 550°C-950°*** annealing at 850°C,the proportion of the FCC phase decreases compared to the cladded coating,and the number of large-angle grain boundaries is significantly ***,the proportion of grains with sizes below 50μm increases from 61.7%to 74.3%.The micro-hardness and wear resistance of the cladded coating initially increases but then decreases with an increase in annealing temperature,indicating that appropriate annealing can significantly improve the mechanical properties of the CoCrFeMnNi HEA coatings by plasma *** micro-hardness of the CoCrFeMnNi HEA coatings after annealing at 650°C increases to 274.82 HV_(0.2),while the friction coefficient decreases to below 0.595.

关键词： plasma cladding CoCrFeMnNi HEA coating process optimization annealing microstructure and mechanical property

Physical Characteristics of plasma cladding Fe-Cr-Nb-Si-Mo Alloy cladding Layers on Different Substrates

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2020年第4期35卷 820-824页

作者： GAO Guijun LI Kang CHEN Weiwang ZHANG Hongbin YANG Xiaobing ZHANG Hongyu LI Junxia College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Shandong Province KeyLaboratory of Mine Mechanical Engineering Shandong University of Science and TechnologyQingdao 266590China JMC Heavy Duty Vehicle Co. Ltd.Taiyuan 030024China

A plasma cladding experiment was carried out to investigate the characteristics(surface hardness,microstructure,friction,wear properties from different substrates to the cladding layer and the bond strength)of plasma cladding Fe-Cr-Nb-Si-Mo alloy cladding layers on different *** order to improve the abrasion resistance of the scraper middle trough,the plasma cladding technique was used to clad the alloy ceramic powder Ig7 on the surface of the middle trough NM450,WH60A,Hardox450,and Weartuf450 to create Fe/Cr/Nb/Mo/V cladding *** on the experiment results,the microstructure,friction and wear properties of the four cladding layers were analyzed,and the bond strength between the cladding layer and the substrate was also *** experimental results show that the main phases of the four cladding layers are martensite and all kinds of metal carbides((Nb,Mo)C,VC,and Cr7C3).WH60A surface cladding layer has shown good friction and wear properties.

关键词： plasma cladding organization structure microhardness bond strength

TiC/Fe cermet coating by plasma cladding using asphalt as a carbonaceous precursor

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2008年第4期18卷 447-454页

作者： Junbo Liu School of Mechanical and Electronic Engineering, Weifang University, Weifang 261061, China School of Mechanical and Electronic Engineering Weifang University Weifang 261061 China

A new Ti-Fe-C compound powder for plasma cladding was prepared by heating a mixture powder of ferrotitanium and asphalt pyro-lyzed as a carbonaceous precursor. The carbon by the pyrolysis of the asphalt acts as a reactive constituent as well as a binder in the compound powder. The TiC/Fe cermet coatings were prepared by plasma cladding with the compound powder. Results show that the Ti-Fe-C compound powder has a very tight structure, which can avoid the problem of the reactive constituent particles being sep- arated during cladding. The TiC/Fe cermet coating presents a typical morphology of plasma cladding coatings with two different lam- inated layers:one is the composite layer in which the round fine TiC particles (<500 nm) are dispersed within a Fe matrix, the other is the paragentic layer of TiC and Ti2O3. The coating shows high hardness and excellent wear resistance. The surface hardness of the coating is 68 ± 5(HR30N). In the same fretting conditions, the wear area of Ni60 coating is about 11 times as much as the TiC/Fe cermet coating.

关键词： plasma cladding TiC/Fe cermet coating Precursor Microstructure Wear resistance

Study on Fe-based alloy Fe-Cr-Ti-C layers by reactive plasma cladding

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Welding 2013年第1期22卷 59-64页

作者：刘均波李惠琪王朋 School of Mechanical-electronic and Vehicle Engineering Weifang University Weifang 261061 Institute of Material Shandong University of Science and Technology Qingdao 266510

Fe-based alloy Fe-Cr-Ti-C composite layers with and without titanium （ other powder ingredients are about the same） were fabricated on Q235 steel by plasma cladding process with high-energy plasma jet as heat source. Microstructure , phase composition and micro-hardness of the layers were investigated by optical microscope （OM）, X-ray diffraction （XRD）, electron probe microanalysis （ EPMA ） and micro-hardness tester. The results show that the grains of the cladding layers with Ti are much finer than that of the Fe-based cladding layer without Ti. Compared with the cladding layers without Ti, there are more shingle crystals in the cladding layers with Ti and the hard phase （ Cr, Fe ） 7 C3 of the eutectic in the layers increase gradually. However, as increasing titanium content in the alloy powder, the hard phase （Cr, Fe ） 7 C3 in eutectic structure of the cladding layer increases gradually, restraining （ Cr, Fe ）7 C3 carbide precipitation and decreasing the average and maximum hardness of the cladding layer.

关键词： plasma cladding Fe-based alloy titanium carbide micro-hardness

Influence of process parameters on microstructure of reactive plasma cladding TiC-Fe-Cr coating

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Welding 2021年第2期30卷 35-41页

作者： Liu Junbo Wang Limei Liu Junhai School of Mechanical-electronic and Vehicle Engineering Weifang UniversityWeifang 261061China School of Information and Control Engineering Weifang 261061China Naval Architecture&Marine Engineering College Shandong Jiaotong UniversityWeihai 264209China

A certain amount of Ti was added to the plasma cladding Fe-Cr-C coating in the early stage in order to improve the quality and properties of the ***-Fe-Cr-C composite powder was prepared by precursor carbonization-composition *** situ synthesized TiC-Fe-Cr coatings were fabricated on substrate of Q235 steel by plasma cladding process with the composite *** of the coatings with different process parameters,including cladding current,cladding speed,number of overlapping cladding layers,were analyzed by scanning electron *** results show that the structure of the TiC-Fe-Cr coating is greatly affected by the cladding current,the cladding speed and the overlapping cladding *** this test,when the cladding current of 300 A and the cladding process parameter of the cladding speed of 50 mm/min are clad with three layers,a well-formed and well-structured TiC-Fe-Cr coating can be obtained in this ***-Fe-Cr coating has good wear resistance and good load characteristics under dry sliding wear test conditions.

关键词： TiC-Fe-Cr coating plasma cladding process parameters microstructure

Effects of TiB_2+TiC content on microstructure and wear resistance of Ni55-based composite coatings produced by plasma cladding

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2019年第1期29卷 132-142页

作者： Xin-jie ZHANG Hong-zhi CUI Jia-feng WANG Guo-song ZHANG Yu-qiao ZHAO Kang SUN School of Materials Science and Engineering Shandong University of Science and Technology Qingdao 266590 China

TiB2-TiC reinforced Ni55 matrix composite coatings were in-situ fabricated via plasma cladding on steels using Ti, B4C, and Ni55 as precursor materials at different proportions. Effects of TiB2+TiC content of ceramics phase on the microstructure and wear resistance were studied. The results showed that ceramic phases TiB2 and TiC were in-situ synthesized by plasma cladding, and the ceramic phase content significantly affected tribological performance and the wear mechanism of coatings under different loads. The composite ceramics protected coatings from further delamination wear by crack-resistance under a load of 30 N. Severe abrasive wear and adhesive wear were prevented when the load increased to 60 N because of the high hardness and strength of ceramic phases. Moreover, a compacted layer appeared on the wear surface of coatings with high content of ceramic phases, which effectively decreased the friction coefficient and wear rate. The TiB2-TiC composite ceramics significantly improved the wear performance of metal matrix composite coatings by different mechanisms under loads of 30 and 60 N.

关键词： metal matrix composite coating plasma cladding microstructure tribological behavior wear mechanism

Optimization analysis of track comprehensive quality in micro-plasma cladding process

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2018年第10期25卷 2309-2319页

作者： ZHOU Chen TIAN Wen-hua ZHANG Qiao-xin LI Xue-wu TANG Ming-kai School of Mechanical and Electronic Engineering Wuhan University of Technology School of Materials Science and Engineering Huazhong University of Science and Technology

The purpose was to clarify the relationship between the main process parameters of micro-plasma cladding and the comprehensive quality(geometry,microstructure and wear rate of cladding track).Self-fluxing ferrous alloy powders were fabricated on Q235 *** on the uniform design,the distribution of the experimental samples was designed reasonably in the sample space,which greatly improved efficiency and reduced *** a series of microstructural characterization,there was no difference in the phase composition of all samples,but the average grain size had a significant difference,which resulted in the change of wear *** the relationship among micro-hardness,average grain size and wear rate of the track had also been ***,an optimization model was established and the optimal process parameters were obtained with excellent wear rate under the geometric *** correctness of optimization model was verified by experiments.

关键词： plasma cladding optimization model geometry microstructure wear rate uniform design

Microstructure evolution by plasma of WC/Fe-based coating cladding

在线全文

学校读者我要写书评

暂无评论

China Welding 2010年第3期19卷 31-36页

作者：卢金斌梁存杨卫铁孟普 School of Materials and Chemical Engineering Zhongyuan University of Technology Zhengzhou 450007.

The composite coatings were formed by plasma cladding Fe-based alloy（Fe-Cr-B-Si） added 10% , 30% and 50% （mass fraction） nickel-clad WC respectively on Q235 steel. The microstructure evolution and microhardness of the coatings were investigated. The WC particles were completely melted into the composites coating when 10% WC was added, however, when 30% or 50% WC was added, only part of them could be melted in the coatings. Two significantly different solidification microstructures were found. When WC content is 10% or 30%, the microstructure is mainly dendrites and inter- dendrite eutectics, while when the content of WC reaches 50% , it becomes remained WC particles, Fe3 W3 C carbide faceted dendrite and eutectics hypereutectic structure. The microhardness of these three coatings reaches 560- 600, 650 -810 and 920 - 1 100 HVo2 respectively, and is improved with the increasing of WC content.

关键词： plasma cladding nickel-clad WC Fe-Cr-B-Si