结扎橡皮圈应力松弛的研究 (pdf)

    【摘要】 目的 通过定期测量结扎橡皮圈负载后应力的变化，研究它应力松弛的过程及在不同负载下应力松弛率的异同。方法 选取结扎橡皮圈30个，随机分为3组，每组10个，3组试样分别负载100g、150g和200g。通过定期测量结扎橡皮圈在不同负载下的应力，了解应力的变化过程。对3组试样的应力变化进行统计分析。结果 结扎橡皮圈在最初的48h内应力衰减较快，负载48h后残余应力为初始应力的80%左右(78.4%～83.5%)，之后应力松弛的速率逐渐减小，至第32天时残余应力为初始应力的73.1%～85.8%。结论 结扎橡皮圈在不同负载下均存在应力松弛的现象，应力松弛率相同。

    【关键词】 结扎橡皮圈；应力；应力松弛

    【Abstract】 Objective By way of measure the stress of elastomeric ligatures periodically after three different loads were load on, to evaluate the stress relaxation of it. And compare the stress relaxation of the three different loads. Methods The randomly selection elastomeric ligatures thirty, divide into three groups randomly, each group of ten, every group distinction load 100 grams, 150 grams and 200 grams. In this experiment measure the stress of elastomeric ligatures under different load regularly. Carries on the comparison to different load rate of changes and makes the statistical analysis. Results This research discovered elastomeric ligatures are biggest in the experimental initial 48 hour internal stress weaken, after load 48 hours remaining stress for about initial stress 80%(78.4%～83.5%). After 48 hours their stress relaxation speed reduces gradually, to 32nd day remaining stress for initial stress 73.1%～85.8%. Conclusion The rate of stress relaxation of the rubber ring ligatures on different loads are the same. ......