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PEEKceramic-filledPEEK
日期:2019-01-24 11:30
Polyformaldehyde is a kind of hard and dense material with smooth and lustrous surface. It is yellowish or white and its thin wall is translucent. The combustion characteristics are easy to burn, and continue to burn after fire. The upper end of the flame is yellow and the lower end is blue. It melts and drips, and has strong irritating formaldehyde odor and fishy odor. Polyformaldehyde is a white powder, generally opaque, good coloring, specific gravity 1.41-1.43 g/cubic centimeter, shrinkage rate 1.2-3.0%, forming temperature 170-200 C, drying conditions 80-90 C for 2 hours. The long-term heat resistance of POM is not high, but it can reach 160 C in the short term. The short-term heat resistance of homopolymer POM is higher than that of copolymer POM by more than 10 C, but the long-term heat resistance of copolymer POM is higher by about 10 C than that of homopolymer POM. It can be used for a long time in the temperature range of - 40 ~100 C. POM is easy to decompose, decomposition temperature is 280 C, when decomposition there are irritating and corrosive gases. Therefore, the die steel should be made of corrosion resistant materials.
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