Two natural rubber (NR) compounds of hardness shore A 60 and 70 with 10 different biaxial displacement/twist paths were investigated using an axisymmetric cylindrical hollow dumbbell specimen. The effects of the proportional and non‐proportional loading modes on the fatigue life are discussed. In total, 52 fatigue test results are reported with fatigue life results of 3,918 to 488,000 cycles. The effect of the channel phase on the fatigue life is discussed.

中文翻译：

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比例和非比例载荷下硫化天然橡胶的疲劳

使用轴对称圆柱中空哑铃试样研究了两种硬度为A 60和70的天然橡胶（NR）化合物，具有10种不同的双轴位移/扭转路径。讨论了比例和非比例加载模式对疲劳寿命的影响。总共报告了52个疲劳测试结果，疲劳寿命结果为3,918至488,000个循环。讨论了通道相对疲劳寿命的影响。