| The three-dimensional flow impeller is a kind of channel parts with complex surface, widely used in aerospace, water conservancy and hydropower, chemical industry, metallurgy, dynamic and other fields. An aircraft engine contains multiple impeller, impeller is a key part of liquid rocket engine. In civilian industry, the three-dimensional flow impeller has been applied in hydraulic turbine, steam turbine, expander, pump, blower, compressor and other equipment, the impeller is one core part of automotive turbochargers. Whether military or civilian, three-dimensional flow impeller has broad application prospects.The impeller manufacturing process level directly affects the overall performance of the device, particularly in the aerospace industry, in order to improve the performance of the engine, the impeller manufacturing accuracy is very high, and impellers often work in high temperature and pressure environment, which made more stringent requirements on the manufacturing process of impeller. Through continuous development and improvement, Impeller manufacturing process now has developed such as electrolytic machining, EDM, precision casting, precision forging, CNC milling and other processing technology.This paper presents a digital manufacturing method based on rapid prototyping for three-dimensional flow impeller. The resin coated sand and the pearl sand were used as molding materials, rapid prototyping technology were used to produce impeller mold and casting to obtain a metal impeller. At the same time explored the feasibility of shell type impeller manufacturing method based on rapid prototyping. Finally, the precision of impellers were evaluated and analyzed.This paper used the 17 leaf impeller as an example, designed a partitioning scheme based on rapid prototyping technology, describe data processing method and produce process for producing impeller mold by PIRP and SLS in detail. Explored the use of rapid prototyping process technology to produce coated sand sample, make high-temperature water glass shell by coated sand sample, and then cast to obtain samples of metal impeller. Three-dimensional computer-aided detection technology was used to test the precision of impellers produced by PIRP, SLS and shell method. The test results showed that the blades’warping deformation of the impellers which produced by PIRP, SLS were not obvious. Most of the error less than ±0.5mm.The sharp of the impeller which produced by shell method were warped. Finally, the precision of three impeller manufacturing methods were compared, and the warping deformation of shell method was analyzed. |
