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Analyze the characteristics of plastic raw materials for you

　　1. Plastic raw materials swell when heated, and the coefficient of thermal expansion is much larger than that of metal;

　　2. The rigidity of general plastic raw materials is one order of magnitude lower than that of metal;

　　3. The mechanical properties of plastic materials will decrease significantly under long-term heating;

　　4. General plastic materials will show permanent deformation under long-term stress at room temperature and under stress lower than their yield strength;

　　5. Plastic materials are very sensitive to notch damage;

　　6. The mechanical properties of plastic raw materials are generally much lower than that of metals, but the specific strength and specific modulus of some composite materials are higher than that of metals. If the product design is reasonable, it will give full play to its advantages;

　　7. Generally, the mechanical properties of reinforced plastic raw materials are different;

　　8. Some plastic materials will absorb moisture and cause changes in size and properties;

　　9. Some plastics are flammable;

　　10. The fatigue data of plastic raw materials are still very few, which should be considered according to the application requirements.

Source: Jiangmen engineering plastics http://m.latexbbs.com/