功能梯度材料快速成形过程建模与控制

Modeling and Control of Rapid Deposition for Functionally Gradient Material Components

在三坐标雕刻机上开发出一种功能梯度材料增材制造装置,在低于水的凝固点温度下,将两种材料的水基膏体以一定比例进行挤出沉积,形成梯度材料零件。在该三维零件沉积成形过程中,配置好的材料不可避免地会存在结块和气泡现象,当结块分解或气泡释放时,会导致沉积过程中的挤压力不断变化,使得成形过程不稳定,成形零件质量差。在分析三维梯度材料沉积成形过程的干扰因素的基础上,通过实验建立了沉积过程中挤压力的动态模型,采用最小二乘方法进行系统辨识,完成了最小方差自适应挤压力控制器的设计,并用两种不同颜色的腻子粉(CaCO3)进行实验,验证了功能梯度材料快速沉积原理的可行性和控制器的有效性。

A new additive manufacturing equipment built on engraving machine was developed for the manufacture of FGM components,which extrudes two water-based materials in a certain proportion belowed the temperature of water solidification point.In the deposition processes of three-dimensional parts,the agglomeration and bubbles will inevitably exist in the configuration of the materials.When the release of the bubbles and the decomposition of agglomeration,the extrusion force of deposition processes was changed at any time,the deposition processes were unstable and the quality of deposited parts was hardly guaranteed.Analyzing the various process parameters and disturbances affected on the deposition processes of gradient material components,based on the plentiful experiments,this paper constructed the dynamic model of the deposition processes and the recursive least squares method was used to complete system identification.To test the feasibility of the FGM rapidly deposited and the validity of controller,two different colored Calcium carbonates（CaCO3）were tested.