The high-temperature alloy thin-walled casing casting has a complex double-ring structure with multiple hollow support plates and uneven wall thickness, which causes the casting to shrink inconsistently during the cooling process, causing the net dimensions of the inner and outer rings of the casting to be unstable and deviating from the design drawings. Require. By analyzing the entire process of the casting and the impact of the process plan on the shrinkage of the casting, we found out the basic reasons and rules for the deviation of the casting from the design requirements, and repeated measurements and data analysis of molds, wax parts, and metal parts to propose improvement plans and conduct After verifying the plan, the casting dimensions were effectively improved and met the design requirements.
In order to meet the needs of lightweight and low-cost aero-engine structures, the aviation manufacturing industry has adopted high-temperature alloy thin-walled casing integral precision casting technology to replace the casing manufacturing technology of separate parts processing and assembly. The integral casting of high-temperature alloy thin-walled receivers is different from casting in the traditional sense. Not only forming is required, but also the shape and dimensional accuracy of the casting must be accurately controlled to meet the requirements of component assembly. The K4169 high-temperature alloy thin-walled casing casting we developed is a typical representative of this type of casting. Not only does the internal and external metallurgical quality and surface quality of the casting require high requirements, but the dimensional accuracy requirements of the casting are even stricter. The diameter of the casting is φ800mm. In terms of dimensions, the tolerance value is 0.6mm, and it is ensured that the inlet and exhaust areas of the casting flow path surface meet the design requirements. It integrates the dimensional accuracy requirements of professional manufacturing such as casting, processing, and assembly, all guaranteed by casting, and the casting dimensions Control is very difficult. In the actual application process of selecting and revising mold design parameters, designing based on traditional experience can no longer meet the final requirements of the product.
In view of the fact that the inner and outer ring dimensions of the high-temperature alloy annular casing casting could not fully meet the design requirements, a series of experimental research work was carried out. Through the analysis of the casting process plan, solidification, tooling, casting and other dimensional measurements, data analysis, simulation design, etc., After exploring the shrinkage rate of thin-walled annular structural parts with ceramic cores and the difference in shrinkage of different flow channel cross-sections, the mold design parameters were readjusted and the mold improvement plan was determined to ensure that the casting size met the design requirements.
