Ren G.,CSR Qishuyan Co.
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys
The process redundancy of investment casting Cr20 stirring rod with sodium silicate as binder is only 2 mm. The casting defects occur such as over-size of blind hole, shell crack during pouring process, metal bean and inclusion in the stirring rod during production. Some measure were adopted to eliminate the mentioned casting defects through correcting wax pattern to control size of blind hole, adding shell layer and bundling pattern with iron wire to prevent from crack, brushing cast-type position as well as changing interval of pattern assemble and drying time of shell. Source
Guo Y.-F.,Southwest Jiaotong University |
Zhang K.,Southwest Jiaotong University |
Zhang K.,CSR Qishuyan Co. |
Zhang K.,CAS Shanghai Institute of Ceramics |
And 5 more authors.
Beijing Keji Daxue Xuebao/Journal of University of Science and Technology Beijing
A sol-gel method was applied to prepare ZrO2 and Al2O3 coatings on stainless steel (SS304) substrates and to seal the anodic oxidation films of an aluminum alloy. The high-temperature oxidation resistance of as-prepared ZrO2 and Al2O3 coatings was investigated by cyclic high-temperature oxidation tests. The corrosion resistance of the sealed anodic films was investigated by electrochemical impedance spectroscopy (EIS) and exfoliation corrosion method. The experimental results indicate that the high-temperature oxidation resistance of the ZrO2 and Al2O3 coatings is improved with the increasing of coating thickness, and the corrosion resistance of the sealed anodic films is also improved with the increasing times of sealing processes. However, the impedance value and corrosion degree of the sealed anodic films change slightly after more than 8 times of sealing processes. The corrosion resistance of the anodic films sealed with Al2O3 sol performs a little better than those with ZrO2 sol with the same times of sealing processes. Source
Liu K.,Shanghai Institute of Technology |
Zhang C.,Shanghai Institute of Technology |
Pu Y.,CSR Qishuyan Co. |
Hu H.,CSR Qishuyan Co. |
Wu Z.,Shanghai Institute of Technology
Key Engineering Materials
The mechanical properties of materials and structural components, notably fatigue life, brittle fracture, dimensional stability, deformation and crack propagation can be considerably influenced by residual stresses inside bodies. Accordingly, residual stresses analysis is a compulsory stage in the design of parts and structural elements and in the estimation of their reliability under real service conditions. In this paper, x-ray diffraction and hole-drilling method were used to measure residual stresses in diesel iron castings. The purpose is to determine the residual stresses distribution and analyze the annealing process on the influence of residual stress. © (2015) Trans Tech Publications, Switzerland. Source
Zhu J.-C.,Wuhan University of Technology |
Zhu J.-C.,CSR Qishuyan Co. |
Zhu H.-H.,Wuhan University of Technology |
Fan S.-D.,Wuhan University of Technology |
And 2 more authors.
Engineering Failure Analysis
Dynamic lubrication analysis of connecting rod is a very complex problem. Some factors have great effect on lubrication, such as clearance, oil viscosity, oil supplying hole and surface roughness. This work establishes the EHD characteristic of bearing and bush to analyze the peak oil film pressure, min oil film thickness and node force with consideration of deformation and cavitation; then create connecting rod components to calculate the stress distribution with consideration of film lubrication or not and finally contract the results of two conditions. The results show that the stress distribution of two conditions is different in individual positions, but the stress calculation method considering the oil film lubrication is more consistent with the actual working conditions. © 2016 Elsevier Inc. Source
Liu X.-Y.,CSR Qishuyan Co. |
Shen H.-Q.,CSR Qishuyan Co. |
Tao H.,CSR Qishuyan Co. |
Liu H.-R.,CSR Qishuyan Co.
Jinshu Rechuli/Heat Treatment of Metals
Fracture shaft box spring was analyzed by macro-fracture, microstructure at the fatigue crack source, matrix microstructure, surface hardness and room temperature and low temperature impact test. The results show that fatigue crack source formed by surface decarburization of the spring and overloading during too much work stress in the work process is the main cause of the spring fracture. Improving suggestions are brought up. Source