检索结果-南通市图书馆

Evaluation of vibration and sound quality according to battery voltage change while moving a power seat in an automobile forward or backward

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2014年第10期21卷 3844-3849页

作者： kang-seok Seo Doo-seuk Choi Key-sun Kim Department of Mechanical Engineering Graduate School Kongju National University Division of Automotive and Mechanical Engineering Kongju National University

The changes in vibration, sound, and sound quality with changes in the driving voltage of a power seat motor from 12.5 to 14.5 V were measured and analyzed, which was used in real vehicles. BSR(buzz, squeak, rattle), which occurs for the power seat mechanism during sliding operation, was also evaluated. In addition, the results were expressed in terms of sound quality metrics, which measure the RPM change and sound level versus voltage to analyze their statistical correlation. Furthermore, vibration measurement and analysis were conducted simultaneously to determine the noisiest conditions and the source of the noise. The changes in RPM and voltage of a motor, in addition to vibration and noise, were measured at the same time to determine how noise, RPM, and voltage are interrelated.

关键词： seat vibration seat noise sound quality voltage buzz squeak and rattle(BSR)

Study on wear behavior of plasma electrolytic oxidation coatings on aluminum alloy

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2006年第z2期25卷 141-145页

作者： kang Suk-bong LEE Jung-Moo Department of Materials Engineering Korean Institute of Machinery & Materials Gyeongnam 641831 Korea

Thick and hard ceramic coatings were fabricated on A356 aluminum alloy by using plasma electrolytic oxidation(PEO) technique. The microstructure and phase composition of the PEO coatings were examined by using SEM and XRD method. It is found that the PEO coatings are mainly composed of crystalline α-Al2O3 and mullite. The dry sliding wear test of PEO coatings were carried out on a ring-on-ring wear machine. Results shows that there is hardly no wear loss of polished PEO coatings while the wear rate of uncoated aluminum alloy is 4.3×10-5 mm3·(N·m)-1 at a speed of 0.52 m·s-1 and a load of 40 N.

关键词： aluminum alloy plasma electrolytic oxidation ceramic coating wear

Microstructure comparison of ZK60 alloy under casting,twin roll casting and hot compression

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2010年第5期20卷 763-768页

作者：王守仁王敏 kang Suk-bong CHO Jae-hyung School of Mechanical Engineering University of Ji'nan School of Materials Science and Engineering Shandong University Korea Institute of Materials Science 66 Sangnam-dongChangwon 641010Korea

The microstructures of ZK60 alloy under conventional direct as-casting (DC),twin roll casting (TRC) and twin roll casting followed by hot compression (TRC-HC) were analyzed by optical morphology (OM),electron backscatter diffraction (EBSD) and X-ray diffraction (XRD).The deformation condition of hot compression is 350 ℃,0.1 s?*** microstructural evolution under TRC-HC deformation followed by annealing at different temperatures and time was *** results show that TRC provides more modified microstructure compared with *** are found in TRC processing;dynamic recrystallization (DRX),shear bands and twins are found in TRC-HC.A short annealing time has little effect on hardness,while during a long time annealing,it is found that low annealing temperatures increase the micro-hardness and high temperature decreases it.

关键词： microstructural evolution anneal dynamic recrystallization static recrystallization twin-roll casting hot compression magnesium alloy ZK60

Nonlinear Electrical Impedance Tomography Method Using a Complete Electrode Model for the Characterization of Heterogeneous Domains

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2023年第3期134卷 1707-1735页

作者： Jeongwoo Park bong-Gu Jung Jun Won kang Department of Civil and Environmental Engineering Hongik UniversitySeoul04066Korea

This paper presents an electrical impedance tomography(EIT)method using a partial-differential-equationconstrained optimization *** forward problem in the inversion framework is described by a complete electrodemodel(CEM),which seeks the electric potential within the domain and at surface electrodes considering the contact impedance between *** finite element solution of the electric potential has been validated using a commercial *** inverse medium problem for reconstructing the unknown electrical conductivity profile is formulated as an optimization problem constrained by the *** method seeks the optimal solution of the domain’s electrical conductivity to minimize a Lagrangian functional consisting of a least-squares objective functional and a regularization *** the stationarity of the Lagrangian leads to state,adjoint,and control problems,which constitute the Karush-Kuhn-Tucker(KKT)first-order optimality ***,the electrical conductivity profile of the domain is iteratively updated by solving the KKT conditions in the reduced space of the control *** results show that the relative error of the measured and calculated electric potentials after the inversion is less than 1%,demonstrating the successful reconstruction of heterogeneous electrical conductivity profiles using the proposed EIT *** method thus represents an application framework for nondestructive evaluation of structures and geotechnical site characterization.

关键词： Electrical impedance tomography complete electrode model inverse medium problem Karush-Kuhn-Tucker(KKT)optimality conditions nondestructive evaluation of structures

Effect of rolling temperature on microstructure and texture of twin roll cast ZK60 magnesium alloy

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

Transactions of Nonferrous Metals Society of China 2010年第11期20卷 2086-2091页

作者：陈洪美于化顺 Suk-bong kang 闵光辉金云学 Provincial Key Lab of Advanced Welding Technology Jiangsu University of Science and Technology Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of Education Shandong University Korea Institute of Materials Science

Twin roll cast ZK60 alloy strip/sheet with final thickness of 0.5 mm was prepared, and effect of rolling temperature on microstructure and texture development was investigated using OM and XRD technique, microstructure and texture were measured on specimens subjected to rolling experiment at different rolling temperature, and macrotexture was also evaluated by X-ray diffraction method. In addition, the （1010）and （0002） pole figures were measured, and the tensile test was performed to reveal the influence of rolling temperature on mechanical properties. The results show that the microstrucmre of ZK60 alloy sheet consisted of fibrous structure with elongated grains, and shear bands along the rolling direction after warm rolling. Dynamic recrystallization could be found during the warm rolling process at rolling temperature 350℃ and above. And many fine recrystallized grain could be observed in the shear bands area. It is a little difficult to see the recrystallized grain in the sheet warm rolled at 300℃ because of higher density of shear bands. The warm rolled ZK60 alloy sheet exhibited strong （0002） pole texture, the intensity of （0002） pole figure decreases with the increasing of rolling temperature and the basal pole tilted slightly to the transverse direction after warm rolling.

关键词： warm rolling microstructure macrotexture pole figure ZK60 alloy

Enhancement of Au–Ag–Te contents in tellurium-bearing ore minerals via bioleaching

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 262-270页

作者： Nag-Choul Choi kang Hee Cho bong Ju Kim Soonjae Lee Cheon Young Park Department of Rural Systems Engineering Seoul National University Department of Earth and Environmental Sciences Korea University Department of Energy and Resource Engineering Chosun University

The purpose of this study was to enhance the content of valuable metals, such as Au, Ag, and Te, in tellurium-bearing minerals via bioleaching. The ore samples composed of invisible Au and Au paragenesis minerals(such as pyrite, chalcopyrite, sphalerite and galena) in combination with tellurium-bearing minerals(hessite, sylvanite and Tellurobismuthite) were studied. Indigenous microbes from mine drainage were isolated and identified as Acidithiobacillus ferrooxidans, which were used in bioleaching after adaption to copper. The effect of the microbial adaption on the bioleaching performance was then compared with the results produced by the non-adaptive process. The microbial adaption enhanced the Au–Ag–Te contents in biological leaching of tellurium-bearing ore minerals. This suggests that bioleaching with adapted microbes can be used both as a pretreatment and in the main recovery processes of valuable metals.

关键词： tellurium-bearing mineral bioleaching adaptation Au–Ag–Te Acidithiobacillus ferrooxidans

Study on fracture behavior of SiCp/A356 composites

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2006年第z2期25卷 168-173页

作者： kang Suk-bong Department of Materials Engineering Korean Institute of Machinery & Materials Gyeongnam 641831 Korea

The fracture behavior of SiCp/A356 composite at room and high temperatures was studied. Under tensile stress condition at room temperature, the fracture is mostly a combination of the brittle fracture of SiC particles and ductile fracture of A356 matrix. As the tensile temperature increases, the composite changes the main fracture behavior to the separation fracture of the bonding surface between SiC particles and A356 matrix. When the tensile temperature reaches 573 K, the fracture behavior of the composites is almost the whole separation fracture of the bonding surface, which is the main strengthening mechanism at high temperature. Under the cycle stress condition at room and high temperatures, the main fracture behavior of the composites is always a combination of the brittle fracture of SiC particles and ductile fracture of A356 matrix. However, under the cycle stress at high temperature, cycle behavior of the composites changes from cycle hardening at room temperature to the cycle softening at high temperature.

关键词： SiCp/A356 composites brittle fracture ductile fracture separation fracture

In?uence of Carbon Equivalent Value on the Weld Bead Bending Properties of High-Strength Low-Alloy Steel Plates

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2017年第4期33卷 321-329页

作者： Ki Hyuk Kim In Jun Moon Ki Won Kim Ki bong kang Byung Gyu Park Kwang Seok Lee R&D Center of Dongkuk Steel Mill Co. Ltd Pohang 790-729 South Korea Korea Institute of Materials Science Implementation Research Division Materials Deformation Department 797 Changwondaero Changwon Gyeongnarn642-831 South Korea

The contribution of chemical compositions in terms of carbon equivalent value（CEV） on impending crack propagation during weld bead bend tests（WBBTs） was studied with five different high-strength lowalloy steel plates that underwent different rolling processes. The test showed that cracks developed at the weld joint, easily passed through the coarse-grain heat-affected zone（CGHAZ）, and finally were arrested within the heat-affected zone（HAZ）. An apparent decrease in the average crack length, which consequently indicated improvement in crack arrestability, was found with decreasing CEV. In addition,the relatively fine microstructure in the HAZ of low-CEV steel plates helped in preventing the crack from further propagation. Special emphasis was placed on the empirical expectation of critical CEV above which WBBT might fail.

关键词： Mechanical characterization Steel Welding Fracture Crack arrestability against bending

Fabrication, microstructure and properties of SiCp/Cu heat sink materials

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2006年第z2期25卷 232-236页

作者： kang Suk-bong Korea Institute of Machinery and Materials 66 Sangnam-dong Changwon 641-010 Korea

Cu-coated powder was fabricated by electroless plating process, and the composition and morphology of coated powder were studied. Moreover, Cu-30, 40, 50 vol.%SiCp heat sink materials were fabricated by hot pressing using coated and uncoated powder. And the microstructure and thermophysical properties of the heat sink materials were also studied. The results show that SiCp particles distribute uniformly in heat sink materials and the interface between SiCp particles and Cu matrix is clear and well bonded. On the condition of same volume fraction of SiCp, the thermal conductivity of the material using coated powder is larger than that of the material using uncoated powder. Under experiment conditions, the thermal conductivity and coefficient of thermal expansion of Cu-30 vol.%SiCp heat sink material is 236.2 W·m-1·K-1 and 9.9×10-6/K (30-200 ℃) respectively. It provides important reference data for future experiments.

关键词： heat sink material electroless copper plating coefficient of thermal expansion thermal conductivity