Study Of 3D Printing Molding Precision Bused On Fused Deposition Modeling

Fused deposition modeling(FDM)is one of the most widely used rapid prototyping technologies.As a kind of 3D printing,fused deposition process melts heated thermoplastic filament from the nozzle,and builds the part through a layer by layer deposition method.The rapid prototyping machines of FDM technology have many advantages,such as simplicity,inexpensiveness and efficient operation.And it is widely used in the market.But the process precision of rapid prototyping machines is lower,and how to improve the process accuracy of rapid prototyping is an important direction for researching today.First of all,this paper analyzes various factors that affect accuracy of the FDM process on aspects of preliminary data processing,molding process errors and post-processing errors,and puts forward corresponding countermeasures,providing theoretical guidance for subsequent FDM accuracy analysis.Data processing of rapid prototyping technology directly affects the parts of surface quality,accuracy and efficiency.In order to improve the accuracy and reduce the surface roughness,this paper respectively analyzes the hierarchical slicing processing and supporting add technology in the FDM process.An adaptive slicing procedure is firstly introduced.The procedure selects slicing thickness according to the changes of curvature in reference curve.This method reduces the error from step effect effectively,and reduces the time substantially on the premise of ensuring molding precision.Moreover,this paper analyzes the principles of support technology.Support additive technology is researched through the orthogonal experimental design in the FDM process.The optimum parameters are obtained on the premise of ensuring accuracy,in which the support is easily to be removed.The maximized suspended dimension of prototyping parts are confirmed through test.The result of the experimental research is of great referential value.The design of the nozzle structure affects the quality of parts directly.Stable and enough driving force of friction is the key to improve the forming quality.In the first place,the calculation formula of friction driving force can be derived by theoretical analysis.The influencing factors of friction driving force are analyzed.And the method is ensured to increase the friction driving force by improving the mechanical structure.Furthermore,a kind of remote wire feeder is designed.The deceleration device is increased and the driving force is more stable.At last,thermal analysis is carried out by software ANSYS.The heat distribution of the nozzle is studied through analyzing temperature field and stress field of the nozzle.It provides reference for temperature control and structure optimization design of the nozzle.