Research On The Melt And The Nozzle In Fused Despotion Molding Process

With the growth of social needs and the development of technology,the global marketand economic globalization gradually formed.The competition in products production andsale becoming more and more intense. One of the most focused competitive point of themanufacturing industry is the products’ time-to-market.Therefore we need to shortendesign cycle,what’s more, the designer should come up with specimen and conductessential property test which is according to the present market need as soon as possible.Atlast,make some proper modify according to client is also needed so that we can get thefinalized products which is qualified to put on the market.The current manufacturing industry must also has strong flexibility, only in that casecan the companies meet the increasingly change of users’ demand and also can control thecost to small batch and single production. Overall, that demands manufacturing industrycontinuously made new progress and breakthrough and conduct new technology revolution.Rapid prototyping technology is produced and developed under such a society background.Fused deposition modeling (FDM) which is contained in rapid prototyping technology alsohas the fastest developing speed compared with other varieties of rapid prototypingtechnology. At present, it has become a research hotspot of rapid prototyping technologyand be applied in the related field.This paper take the screw extrusion process of the fused deposition molding (FDM) asit’s research route, analyze the melt’s rheological behavior in the extrusion process, andanalyze the related factors which is influencing the melt extrusion process. On the basis ofthe above research this paper also improving the related parameters of extruder screwwhich can provide us more optimized scheme of screw extrusion.The main research content is as follows:1.Analyze the melt’s form and the rheological behavior which is exist in the fuseddeposition screw nozzle,its main research contents is as follow: First it used theconstitutive equation to describe the flow properties of the polymer, namely how to establish the constitutive equation;The second is to establish the constitutive equation andaccurately solving highly non-linear and non-local hydromechanics control equationsunder the complexity boundary conditions in the machinery processing.2.According to the obtained data we use Proe3d software to establish the geometricmodel and use the related fluid simulation software (FLOTRAN CFD) to simulate theprocess of screw extrusion and certify the results of numerical analysis.At the sametime,get the parameters’ distribution which includes pressure,velocity,flow direction, shearrate and viscosity,this parameters is obtained in the polymer melt’ flowing process.3.The design of temperature control device is closely related to the nozzle’s heatbalance analysis and calculation. Develop and utilize more advanced temperaturemeasuring device and thermostat can improve the precision of temperature measure,reduce the temperature fluctuation, achieve the heat balance in the melt extrusion process.As a kind of control system, fuzzy PID control system has been widely used. In this paper,we use the blur tool which is contained in MATLAB to verifies the stability of this controlsystem.4. Parameters research and optimization of fused deposition screw,the screw is themost important part of the fused deposition screw nozzle,it directly related to the quality ofextrusion nozzle and its productivity.Analysis the parameters’ influence on the stability ofthe discharge and the impact of production situation on the basis of optimized analysis ofscrew parameters. In order to make the material reach the best extrusion.Optimizingextrusion device according to the factors that influence extrusion stability and extrusionefficiency.