Optimization Of Patternless Casting Manufacturing Based On Additive Manufacturing Technology

Additive Manufacturing technology is a new material processing method, which is one of the most promising technology in the 21 st century and has a broad application prospect in many fields of national economy.This paper aims at optimizing Patternless Casting Manufacturing(PCM) process based on Additive Manufacturing technology, including aspects of its molding materials optimization experiment, process parameter optimization experiment, molding process, post-treatment and pouring process,and carry on the technological feasibility test.In order to improve the strength of the cast,from a series of molding qualities with sand granularities of 100/200 mesh、70/140 mesh、50/100 mesh、40/70 mesh, We found that that in the process of PCM, modelling process without tight operation in traditional process modelling,mould compactness mainly depends on the granularity of sand. Through the establishment of ideal sand accumulation model, We computed that available factors influencing the tensile strength of mould. After series of verification of PCM process modelling experiments, the results show when the binder kept constant, the size of bonding-bridge, tensile strength of mould increase with the increase of sand granularity. Confirming the original grain size of PCM process is 100/200 mesh.The PCM process mold exists the problem of high gas evolution, this paper proposed measures from two aspects to reduce casting gas evolution. On the one hand, diluting resin, confirming the alcohol as resin dilution,and optimizing the ratio of added diluent is 30%, which reduces the resin content effectively; On the other hand, introducing the interlayer baking process, including confirm the baking time as 20 s and temperature is 100 ℃ in the mould forming process, which can accelerate the diluents and the water evaporation during the curing reaction in the process, thus reduces the gas evolution of mould.The foundamentals of liquid infiltrating and solidfying in space of sand grain and factors determing the shape are studied deeply to increase forming precision of PCM process modeling. The issue of seepage in PCM is researched qualitatively based on seepage theory. Physical model and basal equation are established in company with its solution. Through the establishment of percolation model, solving seepage equation, and We can use the percolation theory to research seepage problem in PCM process qualitatively. This can get a method to set to the thickness of slice is 0.5 mm, and the curing line width is 1.3 mm. Thus can get optimal mould strength and surface quality of value.In this paper, through the above several aspects of research, We improve the PCM process cast tensile strength effectively,surface quality and dimensional accuracy,reduce casting gas evolution, and further improve the quality of the casting mould. Using PCM process to implement the ladder block casting modelling test. Choosing molding materials which had optimized,and setting process parameters to, printing out ladder block casting successfully.The performance of ladder block casting in line with the actual production requirement, The application of these measures accelerate the process of the PCM technology commercialization.