Study On Semi-Solid Aluminum Alloy Rheo-Die-Casting Technique

Traditional die-casting internal defect ratios are always high, and can not easily do the thermal treatment, so how to reduce these defect ratios is an emergent question which needs to be solved has already gathered much concern of scholars.The paper systematically does some research on semi-solid rheological forming technology mainly on carburetor part which is made of A356 aluminum casting alloy. And the study uses the cooling slope method to prepare semi-solid slurry, then does analysis and research on the influence of rheological die-casting technical parameters to the performance of castings. Mechanical property test shows that if craft is not been well controlled, it will produce porosities as well, though under semi-solid conditions. However comparing with the one under the same conditions of traditional die-casting, these detects is much smaller. Therefore, need to do further study on the controlling of die-casting technical parameters, the result shows the good quality of surface and no porosities inner, and solves the problems that traditional die-casting can not solve. By now, the superiorities of semi-solid rheological die-casting are externalized. Research method and main results is as following:Using electrical resistance furnace and cooling slope to melt A356 aluminum alloy and gain the semi-solid slurry. And mechanics of this method is to use the gravity itself to produce the primary grain on the surface when flowing down with the cooling slope, then gains the self-stirring and crystals extricating to form the uniform and near-circular structures of semi-solid slurry. Equipments of this method are simple and easy to put into effect, also the semi-solid structures is proper.Designing and analyzing the carburetor die-casting mould to have a whole idea of every part function, then using the mould to do the comparing experiment of traditional and semi-solid rheological die-casting. To make research on the influencing factors of thin-wall carburetor structures and internal defects which are connecting with die-casting technical parameters. Using the universal test machine and impact test machine to measure the mechanical properties and also using the metallographic analysis machine to do the microstructures observation of A356 aluminum alloy under different technical parameters. The result shows that these parameters should be strictly controlled or the mechanical properties will fall down because of the defects producing, though under semi-solid rheological die-casting. However, the results of semi-solid one...