# 폴리프로필렌의 변형속도 및 온도변화에 따른 판재 인장시험 평가

• Kim, Kee Joo (Department of Mechatronics Engineering, Tongmyung University)
• 김기주 (동명대학교 메카트로닉스공학과)
• Accepted : 2018.08.03
• Published : 2018.08.31
• 32 2

#### Abstract

A tensile test evaluation of a polypropylene plate was carried out using an Instron tester with a capacity of 500 kgf. To evaluate the strain rate sensitivity of the polypropylene plate with a thickness of 0.8 mm, a tensile test was performed at room temperature through strain rate variations from $5{\times}10^{-4}/sec$ to $5{\times}10^{-2}/sec$. From these, the changes in strength due to the strain rate change and temperature change were compared. As a result of the experiment, the strength increased with increasing initial strain rate. Polypropylene was found to be a material with a positive strain rate sensitivity. In addition, the high temperature tensile properties of the polypropylene plate were evaluated using high temperature tensile tests at 80, 120, and $160^{\circ}C$. The strength decreased with increasing temperature. In particular at $160^{\circ}C$, the tensile strength decreased to zero. The increase in yield strength and the tensile strength at room temperature, $80^{\circ}C$ and $120^{\circ}C$ were similar. At $160^{\circ}C$, however, there was almost no increase in strength because the stress approached zero. In the high temperature tensile test, the tensile strength increased more than the increase in yield strength with increasing strain rate.

#### Keywords

Polypropylene;Strain Rate;Temperature;Tensile Test;sheets

#### References

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