聚乙烯管道材料在宽温度和宽应变率范围压缩性能实验研究

Experimental study on compressive property of polyethylene pipe material within wide temperature and wide strain rate range

管道用聚乙烯(PE)材料除承受静荷载外,还会承受动态荷载和不同温度的作用,因此研究聚乙烯材料在静、动态荷载及不同温度下的力学性能是有必要的。对PE管道材料进行不同温度和不同应变率的压缩实验研究,获得PE在-70～120℃和10^(-4)～10~3 s^(-1)范围内应力-应变曲线,分析应变率和温度对PE屈服应力的影响规律。结果表明:屈服应力随温度降低和应变率增大而增大;在-70～120℃和低应变率条件下,屈服应力与温度关系可以用带指数函数多项式进行描述;在室温条件和应变率为10^(-4)～10~3 s^(-1)范围内,屈服应力随应变率的关系较为复杂。

The polyethylene material for pipe not only subjected to static loads,but also subjected to dynamic load and differ- ent temperature,so the research of polyethylene material under static and dynamic loads and mechanical properties under different temperatures is necessary. By compression bar test device and material testing machine,and the stress-strain curves of PE within the temperature range of -70-120 ℃ and strain rate range in 10^-4-10^3s^-1 were obtained and the influence rule of strain rate and temperature on yield stress of PE was also analyzed. The results showed that the yield stress increases with the decreasing temper- ature and increasing strain rate. Under the temperature of -70-120 ℃ and low strain rate,the relation of yield stress and tempera- ture can be described by exponerftial function polynomial. Within the range of room temperature and strain rate being 10^-4-10^3s^-1, the relation between yield stress is relatively complicated.