Research Initiation: Closed-loop Shape Control During Hot Isostatic Pressing Process

热等静压（HIP）工艺中的一个重要问题 过程是形状变形的发生，这极大地限制了 热等静压作为净成形或近净成形加工潜力 技术. 本研究的基本目的是探讨 使用反馈控制原理来减少不可预测的 由于模型不准确和过程干扰而导致的形状变形。 反馈补偿是通过调整HIP来实现的 基于致密化的真实的时间的温度和压力 现场涡流传感器提供的信息。 由于 多输入多输出，非线性和不确定性的性质， 热等静压过程动态，模型预测的修改版本 控制方法将被用来设计计算机控制系统。 将构造一个状态估计器来估计密度 根据涡流提供的阻抗值确定状态 传感器. 该项目的研究成果不仅将导致 闭环计算机控制系统，用于提高HIP质量， 生产力，但也可能有助于发展 用于其他材料加工的实时反馈控制系统 系统. 如果成功，这项研究将允许生产 由具有高度一致性的粉末金属制成， 形状准确，减少废品。

An important problem with the hot isostatic pressing (HIP) process is the occurrence of shape distortion, which greatly limits the potential of HIP as a net or near net shape processing technology. The basic objective of the research is to explore the use of feedback control principles for reducing the unpredictable shape distortion due to model inaccuracy and process disturbance. The feedback compensation is achieved by adjusting the HIP temperature and pressure in real time based on the densification information provided by the in-situ eddy current sensors. Due to the multi-input multi-output, nonlinear and uncertain nature of the HIP process dynamics, a modified version of the model predictive control method will be used to design the computer control system. A state estimator will be constructed to estimate the densification status from the impedance values provided by the eddy current sensors. The research results from this project will not only lead to closed-loop computer control systems for improving HIP quality and productivity, but may also be useful for the development of real-time feedback control systems for other material processing systems. If successful, the research will allow the production of part from powdered metal with a high degree of consistency and shape accuracy, reducing scrap.