薄膜材料弯曲测试方法的验证研究

Verification of a Bend Testing Method for Thin-Film Materials

在国家标准《微机电系统(MEMS)技术薄膜材料的弯曲试验方法》制定阶段,为验证该标准中测试方法的准确性和实用性,设计并制备了4种尺寸的悬臂梁结构,并利用纳米力学测试系统记录其弯曲形变过程,获取了待测结构的形变-应力曲线。通过该标准可实现薄膜材料弯曲力学性能的有效表征。对弯曲试验的测量数据进行分析,实验结果表明,基于该测试方法10次的重复性达到0.32%,同类型的测试结构具有较强的规律性,靠近悬臂梁根部的测试点表现出更高的机械刚度,与理论预测完全一致。因此,该标准中所采用的弯曲测试方法可重复性好,可用于薄膜材料的弯曲力学性能测试。

In the process of developing the Chinese national standard “Micro-electromechanical systems technology-Bend testing methods of thin film materials”,cantilever beam structures with different sizes were designed and prepared to verify the accuracy and practicality of the method used.Their bending deformation processes were recorded by nanoindentation instrumentation,and the deformation-stress curves of the structures were obtained.The bending mechanical properties of thin-film materials can be effectively characterized based on this standard,and the measured data from the bending tests were analyzed.The experimental results show that the repeatability over 10 tests reached 0.32% using this testing method,and the same type of test structure exhbits strong regularity.The test point near the anchor of the cantilever beam exhibits high deformation stiffness,fully consistent with the theoretical prediction.Therefore,the bending test method used in this paper has good repeatability and can be used for testing the bending mechanical properties of thin-film materials.