Research On The Low Temperature Resistance And Impact Resistance Of Polymer Materials

As the national strategy of "Belt and Road", the development of high-speed rail have caused a wide effect on the whole world. In this case, localization of key parts is the key to build independent intellectual property rights of high speed emu. Therefore, this paper aims at polymer materials in the critical parts of high speed emu, recommending the SCCJ4 as desired through a series of characterization methods analyzing the difference of different ratio in mechanics performance of polymer material.In this article, we developed a series mechanical performance experiments combining with other experiments such as ultraviolet resistance, a low temperature resistance and water absorption test. The results are as follows.1. The mechanical performance of cold resistant and impact resistant of polymer material whose Tensile strength reaches 170Mpa enhances evidently after combining fibres. The crystallinity of fibre composite reinforced material is 10%, the average water absorption rate is 1.25%, and it can hinder the internal crystal and reduce water absorption ability of material.2. fibre reinforced composite material has a good ability of low temperature resistance and antiultraviolet aging ability. When the environment temperature is-40℃, tensile strength of fibre reinforced composite material is 145 mpa. The lowest tensile strength is 147 mpa only decreasing 15%, the maximum of impact strength is 95 j/was, and the maximum of change rate is 10% with ultraviolet in 200 hours. Due to the molecular chain movement blocked and crystallinity decreasing, ultraviolet can cause a certain degree of degradation, also led to a decreasing of the crystallinity to material in a low temperature state.3. Water absorption rate of material is still high and its ascension causes tensile strength to decrease and impact strength to rise in boiling water even through fibre reinforced composite materials are able to reduce the average rate of water absorption. The tensile strength has decreased to 112 mpa declining 36% in boiling condition for 5h.4. Under the effect of water absorption and UV, fibre reinforced composite materials when a equals 0.1, only the factor of water absorption rate have a ratio 2.8 which greater than 2.6, that is boiling has a infection on experiment results through Quantitative analysis of factors.5. It is hard for the fibre inside to form micro channel comparing with polygonal section since it pacts evenly in internal base and has a circle cross-section. The combination of reinforcing fibre reduces the water absorption rate and crystallinity of material, promoting its comprehensive mechanical properties as well, but material embrittlement might be caused by over adding.6. Combining the difficulty and cost of material molding process, we have compared the mechanical performance of other polymers including imported materials with above experiments. The results shows that the SCCJ4 material has a good mechanical performance and ability low temperature resistance with a reasonable cost of forming process.