The Analysis And Experimental Study On The Influencing Factors Of FDM Forming Performance

Fused Deposition Modeling(FDM)process is a class of widely used technique in the field of rapid prototyping technology.Nowadays,it plays an important role in developing new products and producing aerospace parts as well as the design and development of medical equipment.However,as a result of the FDM molding accuracy is not high enough,which restricted its scope of application.In this paper,a detailed analysis of the factors affecting the mechanical properties of the fused deposition molding parts is made that based on the theoretical analysis.First of all,the basic principles of molten deposition molding,molding characteristics,molding materials are described in detail.The defects of fused deposition parts and the main factors that affecting their precision are analyzed and summarized,the factors affecting the FDM parts are analyzed comprehensively,include the principle errors,the manufacturability errors and the post-processing errors.Based on the theoretical analysis,the processing parameters would be configured in order to improve the accuracy and mechanical properties of FDM parts through a lot of experimental investigations.A series of experimental samples were designed by changing the packing density,layer height and filling path respectively for the filling design of the fused deposition process.The tensile test was carried out on the experimental sample,the experimental data was collated and the experimental results were analyzed.The differences of the tensile properties and the precision of the specimens under different filling densities,different layer heights and different filling paths were compared.Through the analysis of the SEM image of fracture surface,the fracture mode is determined,the best strength is determined,the fastest speed,the lowest cost and the highest precision are filled.Among them,the filling density in 90% fracture elongation plummeted,smaller height will weaken the strength of the specimen,the lateral filling path under the good mechanical properties.Finally,the forming direction and forming angle of the molten deposition forming parts are studied,and the experimental samples are constructed under five different forming angles in the horizontal,vertical and perpendicular forming directions respectively.The ultimate tensile strength,elastic modulus and flexural strength of the specimen were analyzed and compared by tensile test,bending experiment and microscopic image observation of the fracture surface which combined with the measurement results of surface roughness to determine the best molding direction and molding angle.Among them,the molding of ZY under the direction of the elongation was significantly lower than that of the molding in YX and YZ direction under the direction of YZ;the size of the test specimen with minimum relative error;the specimen of H-0 and V-0,the tensile strength and elastic modulus,high bending strength and mechanical properties of the best.