To solve the problem of cavitation protection on the surface of aluminum alloy flow-handling components, Ti6Al4V coatings are prepared by in-situ micro-forging assisted cold spraying. Large-size 202 stainless steel particles are mixed into Ti6Al4V powder during the spraying process to promote the plastic deformation of Ti6Al4V powder and form dense coatings. The effects of cold spraying process parameters on the quality of Ti6Al4V coating are investigated using optical microscopy,scanning electron microscopy, microhardness tester, ultrasonic cavitation testing machine, and 3D profilometers, leading to the determination of the optimal process parameters. The results show that the porosity of Ti6Al4V coating decreases with the increase of shot peening particle content. When the shot peening content is 70%(volume fraction), the Ti6Al4V coating is compact and the porosity is only 0.46%. The microhardness of the coating gradually increases to 394HV0.3, which is higher than the microhardness of forged Ti6Al4V alloy(370HV0.3). The cavitation erosion test results show that the cavitation erosion depth of Ti6Al4V coating is only 4.742 µm after 2 h cavitation erosion, and the cavitation erosion resistance of Ti6Al4V coating is 77 times that of Al substrate (365.199 µm). The Ti6Al4V coating prepared by in-situ micro-forging cold spray is dense, has high hardness, and exhibits good interparticle bonding, effectively inhibiting the initiation and propagation of cracks during cavitation, which leads to particle detachment. Therefore, it possesses excellent cavitation erosion resistance.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |