Research On Technology Of 3D Printing Human Organs Model Based On Fused Deposition Modeling

3D Printing technology has aroused the attention of many researchers since it appeared.After nearly 30 years of rapid development, the technology plays an important role in the field of advanced manufacturing. Fused deposition molding process(FDM)becomes a kind of widely used 3D printing technology for simple molding equipment,fast speed and low cost.Transparent silicone models of organs can help doctors to study operation scheme,simulate operation procedure, facilitate doctor-patient communication and students' skill training. Transparent silicone model of human organs can be reproduced from a silicone cast. 3D print human organs model based on FDM is the key step in the process of manufacturing silicone mold so it is directly related to the quality of transparent silicone model.3D print model of human organs based on FDM has the following characteristics:(1) model surface is complex, and reverse modeling is easier to implement.(2) wall thickness of model is not uniform so that the thin wall entity parts may be surrounded by the thick wall entities.(3)the ladder error on the surface of the prototype will be copied into the silicone mold, therefore the surface roughness of the prototype must be given higher requirements.(4) to observe the internal organs model conveniently, the model is divided into many parts and each part is manufactured respectively. In order to guarantee the quality of the silicone mold, the deformation of prototype parts should be as small as possible. This paper focus on the research about the manufacturing process of cardiovascular model, and researches the common problems of 3D print human organs model based on FDM. The paper provides many important references to improve the quality of the sintered parts.This paper rebuild the cardiovascular model based on laser scanning technology and reverse engineering technology, and analyze the key issues in each stage of the model reconstruction.Converse the CAD model to STL format and conduct slice processing, preparing for the forming of the model, manufacture the model based on FDM process desktop-level molding equipment, and manufacturing process parameters setting are analyzed.As for the problem of surface roughness of prototype parts, this paper analyzed the effect of slice thickness and molding direction on the surface roughness of the prototypemodel, and by designing different experiments to study the factors, the test result shows that by reducing the thickness of the layered and setting up the reasonable forming direction can effectively reduce the surface roughness value. Main factors influencing the molding of thin-walled entity are analyzed, and orthogonal test for investigating the significance of each factor is designed, and optimize the process parameters configuration.In FDM process, contraction deformation of molding material will affect manufacturing precision of prototype. This paper analyzes the mechanism of temperature shrinkage of material, and mechanics model between material contraction deformation and the load is established according to the small deflection of thin plate bending stress problem. The method of simulating the model deformation based on the hard killed of finite element is proposed in the paper. According to the results of theoretical analysis, measures for improving the contraction deformation are proposed from the aspects of molding material and molding process. The prototype afte improving manufacturing got good results in the aspect of contraction deformation.