摘要
介绍了利用一种新型的落重和高速摄影实验系统对三种常见的聚合物（ＰＣ，ＰＥＫ和ＰＥＥＫ）在高压应变率下的力学性质的研究结果。所使用的实验系统在常规落重装置的基础上，增加了高速摄影系统，实现了应力和应变过程的同时测量。从而使得在一次实验中可同时获得应力和应变数据，避免了这类实验中常用的变形过程中体积不变的假设，使得结果更加可靠，并可验证材料的泊松比。给出了上述三种聚合物在常温下的真应力与自然应变的关系。结果表明，在室温下，当应变率约为１０００ｓ－１时，这三种材料的屈服应力分别为１２８ＭＰａ，２０４ＭＰａ，和１８０ＭＰａ。三种材料均具有很好的冲击韧性，断裂应变均在５０％以上。对不同环境温度下，ＰＥＥＫ的实验结果表明，随温度的增加，屈服应力将下降。
In this paper,we present our research results on the dynamical mechanical properties of three polymers(Polycarbonate(PC),Polyetherketone(PEK)and Polyetheretherketone(PEEK))under high strain rate with the use of an improved dropweight camera experimental system.As this improved experimental system allows us to take high speed photograph as well as the stress history,we could measure the true stress and true strain of the sample under impact from one shot.This enables us to avoid assuming the volume of the sample is constant during the deformation,a commomly used assumpation in such kind of experiment,and made the experimental results more reliable,and could check the value of Poisson ’s ratio.We present the experimental results of true stress true strain relation of these three polymers under the strain rate of 1000s -1 .The results show that all these three polymers have a good shock toughness.As the polymers are sensitive to strain rate and also the experimental temperature,the results shown in this paper are only valid for the same strain rate and temperature as given in the paper.
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
1999年第1期27-32,共6页
Explosion and Shock Waves
