System Modeling And Analysis Of Sensitivity On Composites Material Formed By Liquid-Solid Extrusion

Liquid-solid extrusion of composite material is a new kind of metal forming process, which has been developed in recent years with a promising practical application prospect for its simple working procedure, low cost and good workpiece performance. But it is difficult to set up an accurate mathematical model because the process is a multivariable nonlinear time varying system. So this process can't be put into practical uses for the difficulties in process parameters control.In this paper, some key factors in the process of composite liquid-solid extrusion had been researched through a large amount of experiments and the common rules of composite liquid-solid extrusion had been obtained. The sample data was built through analyzing the experimental data collected during the experiments, and the model's construction was set up according to the concept of multiple curve fitting. The model parameters had been identified through least-square parameter identification and the sample data had been fitted well. The process parameters had been predicted by use of the model constructed model, and the predicted results coincide well with the experimental data.The extrusion is successfully divided into three ideal stages through the analysis on the pressing force and displacement curve in the process of extrusion. The mathematical model of three import and one export about extrusion velocity, temperature, extrusion force and displacement was constructed by the combination of first order classic least-square algorithm and least-square linear identifying, and the steady control to extrusion force was realized.The sensitivity algorithm is a knowledge of research on the affection of parameters varies to system performance. Combination with pressing force and infuse time predicted model, by using sensitivity algorithm, the affection of cast temperature, mould temperature and infuse pressure on infuse time is researched deeply, and the affection of cast temperature, infuse time and infuse pressure on the pressing force in the origination stage of extrusion process. The sensitivity analysis has huge instructing significance to the selection of parameters. Ideal solving method to the instability phenomena in the pressing process is proposed.In this paper, a set of composites liquid-solid extrusion application software is complied by using of the Visual C++. The visualization and interaction are realized through this software, what's more, the function of mode set up, parameter prediction, data pretreatment and figure exporting are included in it. The composite liquid-solid extrusion process parameters can be predicted and optimized by use of the software. The author's work lays a foundation for the reasonable choose of the process parameters and practical application of the composite liquid-solid extrusion.