|
|
|
| Study on Cracking Mechanism of Laser Clad NiCrBSi Coating |
| YU Ting-1, 2 , DENG Qi-Lin-1, ZHANG Wei-3, DONG Gang-4, YANG Jian-Guo-1 |
| (1. School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200240, China; 2. School of MechanoElectronics, Nanchang University, Jiangxi Nanchang 330031, China; 3. Shanghai Institute of Laser Technology, Shanghai 200233, China 4. School of Materials Science and Engineering, Tongji University, Shanghai 200092, China) |
|
|
|
|
Abstract Cracking mechanism of laser clad NiCrBSi coating was studied through investigation on the microstructure of the coating. The microstructure, crack behavior and chemical compositions of fracture section were investigated. The results show that the Ni60 coating has high crack susceptibility, which still has numerous cracks due to high brittle brittleness and high thermal gradient even if the difference of thermal expansion coefficient between the coating and substrate is low. The reasons are: the coating has a large amount of coarse hard primary phases, hard eutectics and a few of tough phase, resulting in high brittle hardness; the fracture section has slag containing Ca, S, Si elements; the coarse hard phase obstructs the flow of metal liquid, resulting in the discontinuity of the metal matrix; the grain boundary of the coarse hard phase is crack source due to the separation of the liquid films formed on the grain boundary under the action of tensile stress induced in cooling process. In addition, cracks initiate and propagate downwards along grain boundary of coarse hard phase, which has a typical characteristic of hot crack.
|
|
Received: 28 June 2011
Published: 30 July 2012
|
|
|
|
|
|
| [1] |
JIANG Dong-Dong, HONG Fang-Jun, ZHENG Ping. Droplet Oscillations under AC Electrowetting[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(04): 513-518. |
| [2] |
HUANG Xiang-Long, ZHANG Xiao-Jing, BAI Guo-Juan, XU Wu, WANG Hai. Residual Strength Analysis of Thin-Walled Structures with Multiple Site Damage Based on Crack Tip Opening Angle Method[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(04): 519-524. |
| [3] |
LIU Yi-Peng, HU Xue-Yu, CHEN Jia-Luo, WANG Ping-Yang, DU Chao-Hui. Direct Image Correction Algorithm for PIV Measurement of Flowfield within Circular Tube[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(04): 525-532. |
| [4] |
ZHU Han-Hao, PU Sheng-Chun, ZHANG Hai-Gang, LIU Wei, AN Xu-Dong. Verification of the Calculation of Acoustic Field with Typical Bottom Based on Parabolic Equation in Scaled Tank Experiment[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(04): 532-537. |
| [5] |
YANG Jing-Jing-1, LIU Yong-Sheng-1, FANG Wen-Jian-1, FANG Jin-1, PENG Lin-1, YANG Zheng-Long-2, GAO Tian-1, GU Min-An-1. Design and Efficiency of Photovoltaic-Thermoelectric Power Generator with Negative Feedback Characteristic[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(04): 550-554. |
| [6] |
LIU Chen-Yan-1, 2 , PAN Li-1, 2 , ZI Xiao-Chao-2. A Binary-String-Set-Based Algebraic Framework for Policy Composition[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(04): 579-583. |
| [7] |
PENG Yan-Bin-1, ZHENG Zhi-Jun-1, YU Cheng-Bo-2, LI Ji-Ming-3. Automated Negotiation Decision Model Based on Classifier Fusion[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(04): 644-649. |
| [8] |
NING Xiao-Lin-1, ZHAO Yi-Fei-2, CHEN Fei-儿1. Index System and Prosperity Indices of Global Shipping Industry and Applied Research[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(03): 417-422. |
| [9] |
KONG Xiang-Qiang-1, LIN Lin-1, LI Ying-1, ZHANG Dong-2, YANG Qian-Ming-1. Effect of Refrigerant Charge on the Performance of a Direct Expansion Solar Assisted Heat Pump Water Heater Using R410A[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(03): 370-375. |
| [10] |
HUANG Kang, 欧Yang-Guang-Yao , AN Shi-Jie, CHANG Han-Bao. Design and Simulation Research on Double-Staggered Arranged Porous Nozzle[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(03): 434-437. |
| [11] |
WANG Lei, GU Meng-Di. Optimal Reinsurance-Investment Strategies in a Mean-Reverting Market[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(03): 438-443. |
| [12] |
XIONG Hao, YAN Hui-Li, ZHOU He-Ping, LIU Wu-Sheng. Real-Time Optimization Strategy of the Multi-Period Dynamic Vehicle Routing Problems[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(03): 450-453. |
| [13] |
HONG Jiang-Tao-1, YANG Xiao-Yan-1, CHEN Jun-Fang-2. An Empirical Research on the Relationship among Knowledge Management, Knowledge Competence and Core Competence[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(03): 444-449. |
| [14] |
LI Bin-a, JI Jian-Hua-a, b , LI Guo-Wei-a. Study on Supply Chain Robustness Index Mode Considering Profits and Risks[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(03): 484-488. |
| [15] |
XU Shi-Yin, HUANG Xiu-Chang, HUA Hong-Xing. Study on the Band Structure of Hexagonal Chiral Structures[J]. J. Shanghai Jiaotong Univ.(Sci.) , 2013, 47(02): 167-172. |
|
|
|
|
