非接触式视频引伸计在力学性能试验中的应用

Application of Non-contact Video Extensometer in Mechanical Properties Test

为了在材料力学性能试验中推广和应用非接触式视频引伸计,在20kN电子万能试验机上对2A12T4铝合金型材试样进行拉伸试验,用非接触式视频引伸计对该合金的伸长率和宽度变形进行自动测量;同时,在长度方向安装电子应变引伸计跟踪测量,宽度方向缩减变形量在保持相应力值的情况下采用千分尺测量,试样断裂后用工具显微镜测量长度和宽度方向变形;比较用两组测量工具测量出的变形情况,并做出纵、横向变形绝对偏差的平均值曲线,对其进行分析。结果表明,使用非接触式视频引伸计对材料力学性能指标的测量完全能够满足生产和试验研究的需要。

In order to promote and apply non-contact video extensometer to the mechanical test of materials, the tensile testing of 2A12Tg aluminum alloy profile sample is conducted on the 20kN electronic universal testing machine by automatically measuring elongation and width of the deformation for the alloy in non-contact video extensometer. At the same time, electronic strain extensometer is installed in the length direction for tracking measurement, with keeping in the corresponding force value, cut deformation in the width direction is measured by means of micrometer measurement. After the sample cracks, the tool microscope is used to measure the deformation in both length and the width directions. The deformations measured by two groups of measuring tools are compared with each other, and the average value curves in the absolute deviation for the vertical and horizontal deformations are drawn. The analytic results indicate that using non-contact video extensometer to measure mechanical properties of materials is able to completely meet the needs of production and test.