Fabrication of C<sub>sf</sub>/Mg Composites Using Extrusion Directly Following Vacuum Infiltration - Part 1: Monitoring and Acquiring of Process Parameters

Abstract

Many process parameters are involved during the fabrication of C sf /Mg composites using extrusion directly following vacuum infiltration. The selection of suitable process parameters is important for the successful fabrication of composites. This will require a continuous monitoring and collecting system of process parameters. This paper describes how this is performed. The monitoring and collecting system is developed to monitor and control the forming process successfully. The hardware was built with data acquisition (DAQ) card based on PCI and various sensors for temperature, pressure, displacement. The industrial computer is used to process the data collected from the sensors. The data acquisition card is the bridge between the computer and sensors. In order to reduce the signal noise from sensors, the hardware filter circuit is designed. The data acquisition card can not work by connecting the computer and sensors through it simply. It must be operated through the self-developed software. The data colletcing software is developed in this paper. It can realize the parameter monitoring and collecting easily by setting up the hardware through the user friendly interface. The curves of parameters can be displayed on the computer screen and the data can be saved into the database for post-processing. The software also supplies the warning function. When the parameters (for example the temperature of mold) arrives the set value, the computer can sound a note of warning to tell the worker to operate the press. It is demonstrated that the main parameters, such as temperature of mold and liquid metal, the loaded pressure and the displacement of punch, can be monitored and collected in real-time by use of this system. This paper found the base for the further selection of optimized process parameters.