检索结果-南通市图书馆

erosion resistance of Fe-C-Cr weld surfacing layers

在线全文

学校读者我要写书评

暂无评论

China Welding 2001年第1期10卷 8-13页

作者：任振安宣兆志孙大千 Jilin University Changchun 130025 China

Fe C Cr weld surfacing layers with different compositions and microstructures can be obtained by submerged arc welding with welding wire of the low carbon steel and high alloy bonded flux. With the increase of Cr and C in the layers the microstructures are changed from hypoeutectoid steel, hypereutectoid steel to hypoeutectic iron and hypereutectic iron. When the weld surfacing layers belong to the alloyed cast irons the erosion resistance can be raised with the eutectic increase and the austenite decrease. Good erosion resistance can be obtained when the proportion of the primary carbides is within 10 %. The experimental results lay a foundation to make double metal percussive plates by surfacing wear resistant layers on the substrates of the low carbon steels.

关键词： Fe C Cr alloy erosion resistance alloyed cast iron submerged arc weld surfacing

erosion resistance of CaO-Al_2O_3-SiO_2 System Glass-Ceramics

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) 2004年第3期19卷 51-53页

作者：何峰 Wuhan University of Technology

The erosion resistance tests were used to research the erosion wear behavior of CaO-Al-2O-3-SiO-2 system glass-ceramic. With the orthogonal test method, the factors that affect the erosion wear of CaO-Al-2O-3-SiO-2 system glass-ceramic such as particles property, impact angle, impact time, size of particles were *** results show that erosion rate rises along a straight line at the early period of erosion *** the impact time increased,the erosion rate deviates from original staight line,tendency of the erosion rate *** the size of paricle increased,it will have more kinetic energy,the erosion rate of the surface of glass-ceramics ploate rises.

关键词： glass-ceramic erosion resistance impact angle

The Kirkendall effect on erosion resistance of chrome-coated 25Cr3Mo2WNiV and 30SiMn2MoV gun barrel steels

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第10期177卷 246-255页

作者： C.H.Dou P.F.Jin C.Z.Wang J.J.Li C.Zhang J.F.Huang C.Zhang Key Laboratory for Advanced Materials Processing State State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang 471003China

This study aimed to investigate the erosion behavior and mechanism of a newly developed 25Cr3Mo2WNiV steel with a chrome coating using promoted ignition combustion *** erosion threshold pressure and temperature of the chrome-coated 25Cr3Mo2WNiV steel were determined to be 0.2 MPa and 254.3 K higher than those of traditional chrome-coated 30SiMn2MoV ***,Kirkendall voids and inter-diffusion between the Cr coating and matrix were first observed before *** improved erosion resistance of the chrome-coated 25Cr3Mo2WNiV steel was attributed to the suppression of the Kirkendall effect,which minimized heat generation at the Cr/matrix interface by pre-venting oxygen diffusion and reducing oxygen affinity.

关键词： erosion resistance Kirkendall effect Cr coating Gun steel

Effect of Bionic Unit Shapes on Solid Particle erosion resistance of ZrO2-7wt%Y2O3 Thermal Barrier Coatings Processed by Laser

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2018年第3期15卷 545-557页

作者： Panpan Zhang Fuhai Li Xiaofeng Zhang Zhihui Zhang Chaolin Tan Luquan Ren Yueliang Wang Wenyou Ma Min Liu The Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University 5988 Renmin Street Changchun 130022 China Guangdong Institute of New Materials National Engineering Laboratory for Modern Materials Surface Engineering Technology the Key Lab of Guangdong for Modern Surface Engineering Technology Guangzhou 510651 China The State Key Laboratory of Automotive Simulation and Control Jilin University 5988 Renmin Street Changchun 130022 China

Inspired by the coupling phenomena in biological systems, to improve the solid particle erosion resistance of Thermal Barrier Coatings （TBCs）, different kinds of bionic units were made on the coating surfaces using Bionic Coupled Laser Remelting （BCLR） process. The NiCoCrAlYTa/ZrO2-7wt%Y2O3 double-layer structured TBCs were prepared by air plasma spraying. The microstructure, microhardness and phase composition of the as-sprayed and bionic specimens were examined. The solid particle erosion behaviors of bionic specimens as function of bionic unit shape were investigated. The results indicated that the bionic specimens had better erosion resistance than the as-sprayed specimen. The specimen with striation and grid bionic units had the better erosion resistance, while the dot showed the worse. The bionic units were characterized by the dense columnar crystal structure and the high hardness, which are the main reasons for improving the erosion resistance. Under the synergistic action of the shear stress and normal stress on the protrusive coating surface, the erosion failure of the as-sprayed TBCs was proved to be the fracture and spallation of the splats. By contrast, the spallation of segmented bionic unit occurred in the overlapping area between the adjacent laser irradiation, and the erosive unit surface presented the clear and deep furrows, which revealed that the erosion failure mechanism of bionic TBCs was dominated by brittle and some ductile erosion. These results showed more opportunities for bionic application in improving the solid particle erosion resistance of components in the windy and sandy environment.

关键词： bionic thermal barrier coatings erosion resistance laser

Effects of Alloying Elements on Microstructure and erosion resistance of Fe-C-Cr Weld Surfacing Layer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2003年第4期19卷 351-354页

作者： Daqian SUN, Wenquan WANG, Zhaozhi XUAN, Yue XU and Zhenfeng ZHOUSchool of Materials Science and Engineering, Jilin University, Changchun 130025, China Sch. of Mat. Sci. and Eng. Jilin Univ. Changchun 130025 China

Effects of alloying elements on microstructure and erosion resistance of Fe-C-Cr weld surfacing layer have been studied. The experimental results show that increasing C and Cr content favors improving the erosion resistance of the layer, and the excessive C and Cr result in decreasing the erosion resistance at 90 deg. erosion. That Mo, Nb or Ti improves the erosion resistance of Fe-C-Cr weld surfacing layer is mainly attributed to increasing the amount of M7C3 and forming fine NbC or TiC in austenite matrix, but the excessive Mo, Nb or Ti is unfavorable. The addition of Mo, Nb and Ti in proper combination possesses stronger effect on improving the erosion resistance and the erosion resistance (εA) of Fe-C-Cr weld surfacing layer with fine NbC, TiC and M7C3 distributing uniformly in austenite matrix obviously increases to 2.81 at 15 deg. erosion and 2.88 at 90 deg. erosion when the layer composition is 3.05C, 20.58Cr, 1.88Mo, 2.00Nb and 1.05Ti (in wt pct).

关键词： Weld surfacing layer Alloying elements erosion resistance

Effect of Rare Earth Elements on erosion resistance of Nitrocarburized Layers of 38CrMoAl Steel

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2004年第3期22卷 406-409页

作者：上官倩芡程先华 School of Mechanical & Power Engineering Shanghai Jiao Tong University Shanghai 200030 China . Engineering) College of Machinery and Electronics Information Shanghai Normal University Shanghai 201418 China

Effect of rare earth elements (RE) on erosion resistance of nitrocarburized layer of 38CrMoAl steel was investigated. The results indicate that significant improvement occurs in erosion resistance of nitrocarburized 38CrMoAl steel by introducing RE during nitrocarburizing processing as compared with conventional nitrocarburizing processing. Results of mechanical testing show that both hardness and impact toughness of RE-nitrocarburizing layer of 38CrMoAl steel increase as compared with the conventional one. Optical microscopy reveals that there is improvement in the nitrocarburized layer attributed to the introduction of RE, which results in improvement in erosion resistance. Surface morphology observation of tested samples reveals that predominantly furrow-like peelings from plastic deformation are observed for RE nitrocarburizied 38CrMoAl steel, while the furrow-like peeling with initial cross crack and large grinding peelings were observed for conventionally nitrocarburized samples.

关键词： metal materials rare earth elements nitrocarburizing erosion resistance impact toughness rare earths

Bio-cementation for tidal erosion resistance improvement of foreshore slopes based on microbially induced magnesium and calcium precipitation

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1696-1708页

作者： Xiaohao Sun Junjie Wang Hengxing Wang Linchang Miao Ziming Cao Linyu Wu Institute of Geotechnical Engineering Southeast UniversityNanjing211189China School of Civil Engineering and Architecture Wuhan Polytechnic UniversityWuhan430070China

In most coastal and estuarine areas,tides easily cause surface erosion and even slope failure,resulting in severe land losses,deterioration of coastal infrastructure,and increased *** bio-cementation technique has been previously demonstrated to effectively improve the erosion resistance of *** contains magnesium ions(Mg^(2+))with a higher concentration than calcium ions(Ca^(2+));therefore,Mg^(2+)and Ca^(2+)were used together for bio-cementation in this study at various Mg^(2+)/Ca^(2+)ratios as the microbially induced magnesium and calcium precipitation(MIMCP)*** angles,surface strengths,precipitation contents,major phases,and microscopic characteristics of precipitation were used to evaluate the treatment *** showed that the MIMCP treatment markedly enhanced the erosion resistance of *** Mg^(2+)/Ca^(2+)ratios resulted in a smaller change in angles and fewer soil losses,especially the Mg^(2+)concentration below 0.2 *** decreased Mg^(2+)/Ca^(2+)ratio achieved increased precipitation contents,which contributed to better erosion resistance and higher surface ***,the production of aragonite would benefit from elevated Mg^(2+)concentrations and a higher Ca^(2+)concentration led to more nesquehonite in magnesium precipitation *** slopes with an initial angle of 53°had worse erosion resistance than the slopes with an initial angle of 35°,but the Mg^(2+)/Ca^(2+)ratios of 0.2:0.8,0.1:0.9,and 0:1.0 were effective for both slope stabilization and erosion mitigation to a great *** results are of great significance for the application of MIMCP to improve erosion resistance of foreshore slopes and the MIMCP technique has promising application potential in marine engineering.

关键词： Bio-cementation erosion resistance Foreshore slope stabilization Magnesium ions Calcium ions

Microstructures and erosion resistance of plasma-sprayed WCp/NiCrBSi composite coatings

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 2010年第2期19卷 1-5页

作者：韩耀武孙大千谷晓燕李洪梅宣兆志 School of Materials Science and Engineering Jilin University Changchun 130022.

WCp/NiCrBSi composite coatings have been deposited by plasma spraying with the mixed powders of WC-12Ni and NiCrBSi. The coatings consist mainly of WC, γ-Ni, Ni3B, CrB, Cr2B, M7C3, M23C6 and W2C phases. The W2C content increases with increasing WC mass fraction in the powders. The porosity and microhardness of the coatings are related to the coating WC content. The excessive WC results in decreasing the microhardness due to increasing the porosity. The WCp/ NiCrBSi coating with 35 % WC mass fraction powder has more excellent erosion resistance. With an increase of impact angles from 15° to 90° the erosion rate of the coating increases, the erosion rate at 15° impact angle being approximately two times lower than that at 90° impact angle. Based on the wear morphology of the coatings at different impact angles, the wear mechanisms were discussed.

关键词： plasma spraying composite coating microstructure erosion resistance

Effect of Al-deposition on erosion resistance of plasma sprayed thermal barrier coating

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2015年第8期25卷 2587-2593页

作者：张小锋周克崧董淑娟徐伟宋进兵刘敏 .华南理工大学材料科学与工程学院广州510640 广州有色金属研究院新材料研究所广州510650 IRTES-LERMPS Laboratory Université de Technologie de Belfort-Montbéliard

A columnar Al film was firstly deposited on the top of 7%Y2O3？stabilized zirconia （7YSZ） ceramic coating in thermal barrier coating （TBC） system by magnetron sputtering. A vacuum treatment was then carried out at 700 °C for 1 h and 900 °C for 5 h to improve the erosion resistance of Al-deposited TBC. Aα-Al2O3 layer was in situ synthesized on the top of 7YSZ coating via vacuum heat treatment. The microstructure evolution of Al-deposited TBC illustrated that a loose surface-layer and a dense sub-layer formed on the top of 7YSZ coating after vacuum treatment. The phase structures of the as-sprayed TBC and the Al-deposited TBC after vacuum heat treatment were characterized by X-ray diffraction （XRD） and transmission electron microscope （TEM） assisted with focused ion beam （FIB）. Particulate erosion resistances of the as-sprayed TBC and treated TBC were compared at room temperature. In addition, erosion mechanism and schematic diagram were proposed. The results show that the Al-deposited TBC after vacuum heat treatment has better particulate erosion resistance than the as-sprayed one.

关键词： thermal barrier coating erosion resistance in situ synthesis