Week 8

Week eight began the first week of testing with the carbon fiber and PEI in our assembled melting chamber (seen in Figures 1 and 2). We began regulating the temperature of the melting chamber at 216 degrees Celsius, increasing the temperature by 5 degrees every ten minutes. An hour into testing, the pellets of PEI still had not melted, despite our insulation and the thermocouple registering temperatures in the 240-255 degree range. We increased our temperature drastically to 380 degrees, but because of the arrangement of the metal pipes, it was impossible to determine if the PEI in the chamber was actually melting effectively.

Figure 1: assembled melting chamber, uninsulated

Figure 2: assembled melting chamber, uninsulated, top view

Our method of insulation was to wrap vinyl-backed fibreglass sheets around the body of the melting chamber. According to the thermocouple, which was registering temperatures higher than the heater setting, the insulation was effective. Unfortunately, we were still unable to determine the exact melting temperature of our PEI, and further testing and inputs will be attempted.

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