PEI is a high-performance plastic suitable for aerospace weight reduction. This article describes the process of machining aerospace parts from PEI materials, including mold design, injection pressure and temperature control to ensure quality and ultimately dimensionally accurate PEI injection molded parts.
Polyetherimide (PEI) is a high performance specialty engineering plastic that maintains stable performance at both high and low temperatures. Commonly used in the aerospace field PEI structural components can be used to achieve effective weight reduction while reducing the amount of load. The purpose of this paper is to introduce the structural process of PEI material processing for aerospace parts, to how to verify its rationality, and to show the overall process of our company's PEI material processing applied in the cutting-edge aerospace field.
Some aeronautical missions need to be propelled to low altitude orbits of 200 to 800 kilometers, such working environment will be exposed to high-energy radiation and temperature fluctuations, and ordinary polymer materials will be seriously eroded, which will lead to changes in structural and chemical properties, affecting the overall performance of the parts, PEI as a uniform thermoplastic engineering plastics, due to its low coefficient of thermal expansion, mechanical, thermal and electrical properties, and the glass transition temperature of 21.5°C. It is also a thermoplastic engineering plastic, with a low coefficient of thermal expansion. As a homogeneous thermoplastic engineering plastic, due to its low coefficient of thermal expansion and better mechanical, thermal and electrical properties, PEI has a glass transition temperature of 217°C. And due to its excellent flow characteristics, PEI injection molded parts can be obtained efficiently and effectively by means of precision injection molding processing and molding.
In PEI material processing technology, we follow the following principles:
1. Mold design: PEI material has good fluidity and is prone to the phenomenon of sticking to the front mold. Therefore, we need to consider this point in the mold design, choose the appropriate location and shape of the gate, to avoid the melt in the flow process of blockage or leakage and other problems.
2. Injection pressure and injection temperature: In the process of PEI parts injection molding, need to control the injection barrel temperature and mold temperature, usually above 380 ° C, mold temperature control at 170 ° C, to ensure that the PEI material to fully fill the mold, to avoid the emergence of bubbles, shrinkage holes and other defects.
Summarize
PEI material processing in this paper strictly follow the injection molding process standards, in the PEI parts sample sampling stage after a strict quality system control, and then mechanical testing, in the test data are to meet the requirements, fully check the morphological characteristics of the PEI parts, and ultimately get the dimensional accuracy of the PEI injection molded parts.
