Plastic Deformation Behavior of Grains in Small Thin Specimen under Tension

近年来，在微机械和电子器件领域，对细丝、薄膜等小尺寸材料的力学行为的研究十分活跃。一般情况下，小尺寸材料的变形受晶界和晶体取向等微观组织的影响很大。与微结构相比，材料的尺寸越小，影响的幅度就越大。本研究在显微镜平台上对金属薄膜或薄板进行拉伸试验，并对颗粒的变形进行了原位观察。本文讨论了以下几个方面：1.利用聚碳酸酯的热膨胀进行纯钛薄板的拉伸试验；2.用常规的小试件疲劳试验机对纯钛和聚碳酸酯进行拉伸试验；3.用压电台进行纯钛薄板的拉伸试验。讨论了该合金的塑性变形行为和力学性能。在小试件疲劳试验机上对纯钛和聚碳酸酯的力学性能进行了测试。在此基础上对I的结果进行了讨论。第三，利用压电台在显微镜下对纯钛薄板进行了拉伸试验，观察了其拉伸塑性行为。并与I、II的结果进行了比较。

Recently, researches on the mechanical behavior of small-sized material, such as thin wires and films, have been actively done in the field of micro machines and electronic devices. In general, deformation of the small-sized materials is greatly affected by microstructures such as grain boundaries and crystal orientations of grains. The smaller the size of the material becomes in comparison with that of the microstructures, the larger the magnitude of the effect becomes. In this study, tensile tests of metal film or thin plate were carried out on the stage of microscope, and the deformation of grains was observed in situ. The followings were discussed here.I.Tensile test of thin plate of pure titanium using thermal expansion of polycarbonate.II.Tensile tests of pure titanium and polycarbonate by conventional fatigue testing machine for small specimens.III.Tensile tests of thin plate of pure titanium using piezo stage.In the above I, it was confirmed that the tensile test of thin plate of pure titanium was possible using thermal expansion of polycarbonate. The plastic deformation behavior and mechanical properties were discussed. In II, mechanical properties for pure titanium and polycarbonate were obtained by conventional fatigue testing machine for small specimen. The results of I were discussed based on these results. In III, tensile tests of thin plate of pure titanium were carried out on the stage of microscope using piezo stage, and the tensile plastic behavior was observed. The results were compared with those of I and II.