旋转梁测试系统RRM

抗疲劳强度

●工作原理Advance Instrument的旋转梁疲劳测试系统(RRM)的设计是基于旋转梁原理。试件的作用是两点对称受力的简支梁。当旋转半圈时，纤维中原本在中性轴以下的应力由张力变为压缩，反之亦然。在完成旋转后，应力再次被逆转，因此在一次旋转中，试件通过一个弯曲应力(拉和压)的完整循环。●试件加载AI RRM可用于测试直柄试件。标准试件长度为78mm。试样形状可为棒状或管状。大约长25mm(1英寸)或短25mm(1英寸)的样品可以在不影响机器校准的情况下使用。直柄标本采用精密标本夹套固定。应力是通过直接施加自重施加到试样上，以确保精确的加载。 Maximum fiber stress in a specimen having a 4.3 mm diameter is 3200 MPa. While minimum fiber stress in a specimen having a 11 mm diameter is 20 MPa. The system is equipped with a 7" LCD controller that provides easy-to-use in determination of the load weights needed to produce a particular stress at a simple calculation. ● Load Frame Features The standard machine operates at an adjustable integrated variable servo speed of 10 RPM to 6,000 RPM. Speed control is important in testing certain alloys that heat up when highly stressed, and it also allows certain correlations of results between high-speed tests and previous lower speed tests.