| YAO Xin-yu,LIN Qiang,DING Hao-hao,WANG Wen-jian,GUO Jun,ZHU Yi,GAN Lu.Optimization of Process Parameters of Ni60+WC Laser Cladding Coating Based on Taguchi-Grey Relation Method[J],52(11):394-405, 465 |
| Optimization of Process Parameters of Ni60+WC Laser Cladding Coating Based on Taguchi-Grey Relation Method |
| Received:September 29, 2022 Revised:February 13, 2023 |
| View Full Text View/Add Comment Download reader |
| DOI：10.16490/j.cnki.issn.1001-3660.2023.11.034 |
| KeyWord:laser cladding nickel based WC parameter optimization Taguchi-grey relation method signal to noise ratio analysis geometric morphology porosity |
| Author | Institution |
| YAO Xin-yu |
Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu , China |
| LIN Qiang |
Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu , China |
| DING Hao-hao |
Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu , China |
| WANG Wen-jian |
Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu , China |
| GUO Jun |
Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu , China |
| ZHU Yi |
State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou , China |
| GAN Lu |
Chengdu Qingshi Laser Technology Co., Ltd., Chengdu , China |
|
| Hits: |
| Download times: |
| Abstract: |
| Laser cladding is a new surface modification technology. It has the characteristics of fast cooling rate, small heat affected zone, wide powder selection range and high degree of automation. Cladding parameters have a significant impact on the geometric morphology and porosity of the cladding layer, which is an important factor affecting the quality of the cladding layer. At present, the researches on laser cladding process parameters are mainly based on the experiments to improve the mechanical properties of the cladding layer. However, there are few studies on optimizing the porosity and improving the quality of cladding layer. Moreover, the statistical analysis is also needed. Therefore, in the present study, Taguchi-Grey relation method was used to systematically analyze the effect of the cladding parameters, and the cladding parameters of Ni60+25%WC were optimized. The substrate (Q235) was cut into 100 mm × 100 mm × 10 mm square plates, and the MobiMRO fiber laser was used for this study. After the experiment, the sample was cut with wire cutting and polished. Finally, the sample was corroded with aqua regia. Taguchi method was used in the present study to design a three-factor and four-level orthogonal experiment, which greatly reduced the number of the experiments (from 64 to 16) and reduced the experiment cost. At the same time, the cross section geometry, porosity and microstructure of the cladding layer were observed by the optical microscope and scanning electron microscope. The cladding width, the cladding height, the area of the cladding layer, the area of the cladding depth, the pore area and the grain size of the cladding layer were measured by the VHXAnalyzer software and PhenomImageViewer software. With the geometry (cladding width, cladding height, dilution ratio) and the porosity of the cladding layer as the response indexes, the effects of the specific energy and the powder feeding rate on the cladding width, the cladding height, the dilution ratio and the porosity were analyzed. Then, combined with the signal-to-noise ratio analysis, the effect degree of process parameters (laser power, scanning speed, powder feeding rate) on different response indexes was explored. After that, the optimal combination of process parameters was obtained through the grey relation analysis and verified by experiments. Finally, the microstructure of different parts of the cladding layer was compared and analyzed. The laser power had the greatest effect on the cladding width and the porosity of the cladding layer, and the scanning speed had the greatest effect on the cladding height and the dilution ratio of the cladding layer. Increasing the energy input properly could obtain larger molten pool and increase the existence time of the molten pool. It would increase the cladding width and reduce the porosity. The optimized combination of laser cladding parameters included:the laser power of 1 100 W, the scanning speed of 10 mm/s and the powder feeding rate of 7.6 g/min. At this time, the cladding layer was mainly cellular crystal and formed a great metallurgical bond with the substrate. Moreover, the cladding layer had no obvious defects such as pores and cracks, and the wetting angle was smaller than 70°, which met the optimization goal. Moreover, the cladding width increased by 22% (increased from 1 949 μm to 2 383 μm). The dilution ratio is reduced by 58% (reduced from 24.42% to 10.33%), which was closer to the ideal value of 10%. At the same time, the porosity also decreased from 0.329% to 0.306%, with a decrease of 7%. The experiment value (0.672 659) of grey correlation degree was in good agreement with the predicted value (0.626 553), with an error of 7%. At the same time, the grain size of the lower part of the cladding layer was the smallest (3.64 μm), followed by that of upper part of the cladding layer (4.39 μm), and the grain size in the middle of the cladding layer was the largest (5.52 μm). Moreover, the increase of the laser power will cause more WC particles in the cladding layer to dissolve. |
| Close |
|
|
|