Research On Investment Casting Process Of K4169 Alloy Double-ring Thin-wall Cartridge Receiver

This dissertation focuses on the casting process of large-scale double-ring thin-wall casing castings in gas turbine aero-engines.It adopts precision investment casting technology,through the wax mold manufacturing,pouring system design,numerical simulation,shell manufacturing,and casting.A series of process schemes such as the testing of castings were investigated,and a set of casting process plan for this type of large-walled machine was explored.The large-scale thin-wall machine castings have the following structural characteristics.The inner and outer double ring structures are connected by an arc-shaped thin-walled structure.The surface area of the castings is more than 80% of the surface area is a flat plate structure with a thickness of 2 mm,and the thickness of the inner and outer rings is 15-20 mm.In the casting process,due to the complication,thinning,and large-scale structural characteristics of the casting,the liquid metal filling and solidification process is difficult to control,and the metallurgical area is liable to produce thin-walled positions.Casting and cracking,loose and metallurgical defects in thick locations,size of the circumference of the casting,and the position of the thin-walled connecting structure in the middle ring of the inner ring are deformed easily.The main findings are as follows: Completion of the research on the preparation of wax casting molds that can adapt to and meet the requirements of large thin-wall machine tools,including the formulation of the mold structure,the effective matching of wax mold preparation parameters,and the selection of wax materials.According to the metallurgical standards,using the theoretical method and computer numerical simulation of the solidification process,design a reasonable casting system,effectively solve the largescale thin-walled machine boring castings in the investment casting process,the easy emergence of undercast,crack and loose defects.Completion of the study of the preparation of the shell,producing a preheating temperature below 1100?,a pouring temperature of 1500-1530?,the shell at high temperature stability,only minimal shrinkage deformation.Complete the inspection of large-scale double-ring thin-wall machine castings and manufacture castings with dimensional accuracy and metallurgical quality that meet the relevant requirements.