Study On Squeeze Casting Forming Technology Of Aluminum Alloy Door Hanger For High Speed Locomotive

With the increasing speed of domestic railway transportation,the lightweight technology of locomotives is becoming more and more important.Since the door hanger body,which is usually made of cast steel and appears thick and bulky,is of great importance for door opening and closing.So that it is necessary to improve the processing conditions and introduce new materials with high-performance based on the current situation.In this paper,the high-speed locomotive aluminum alloy door hanger was taken as the research object.By combining numerical simulation with experimental methods,the extrusion casting technology was deeply discussed,and the A356 aluminum alloy hanging frame body parts which meet the requirements of enterprises are successfully developed.The main findings and contents of the study are as follows:(1)The processing structure analysis of the hanging frame part and the scheme design of the squeeze casting die were completed.According to the projection area of each part of the casting and the pressure in the casting process,the clamping force and the choice of the equipment type were also calculated.(2)The numerical simulation of different process parameters was carried out by combing the simulation and analysis software Anycasting with the single-factor control variables experimental methods.We also in-depth analyzed the mold filling and solidification process,predicted the trend of defect formation,and abtained the initial production parameters: pouring temperature 645 ?,extrusion speed 15 cm / s,die temperature 200 ?.(3)According to the technological parameters determined by the simulation results,the squeeze casting forming tests of the hanging frame were carried out,and the castings with complete mold filling and good surface quality were obtained.Also the formed castings were partially cut and X-ray non-destructive testing was carried out,and the location of the defect was found to be matching well with the distribution of the simulation results.(4)In order to improve casting perrformance and optimize the technological parameters,three-factor-four-level orthogonal experiments were carried out on pouring temperature,extrusion specific pressure and die temperature.The internal defects of castings were analyzed and verified by scanning electron microscope(SEM)and energy dispersive spectrometer(EDS),and the source of impurities was determined with the formation reasons of voids were also discussed.