臭蜣螂股节表皮纳米力学性能测试

Property Tests of Nano-indentation on Femur Cuticle of Dung Beetle

固体材料性能在纳米尺度和宏观尺度下明显不同。纳米测试技术的发展为固体材料 (包括生物材料 )的纳米力学性能研究提供了手段。已有研究表明甲虫表皮具有层状复合材料结构 ,这种结构在垂直方向的尺寸为微米或纳米量级。进行了试样制备方法的探索 ,介绍了纳米力学测试的基本原理 ,利用纳米硬度计对臭蜣螂前足股节表皮进行了纳米力学性能测试。证实纳米硬度计可有效地对甲虫表皮的纳米力学性能进行测试 ,发现臭蜣螂前足股节表皮在纳米尺度下出现粘弹现象和蠕变效应 ,在最大载荷时的保压过程中 ,压痕深度与时间的变化关系基本符合蠕变幂律公式。

The properties of solid materials in nano-scale are considerably different from those in macroscopic scale. Nano-indentation technique provided a powerful tool for examining the nano-indentation properties of solid materials including the biological surfaces. The research results from other researchers indicated that the cuticle surface of a dung beetle showed a laminative composite structure, which was in the micro- or nano-scale along the vertical direction to the cuticles. In this work, the methods for preparation of specimens of a dung beetle (copris ochus Motschulsky) cuticle were given and the basic principles of nano-indentation testing were introduced. The nano-indentation properties of the femur cuticle of the dung beetle's forelegs were examined with a nano-indenter, which showed a visco-elastic and creep phenomenon. The creep property of the femur cuticle during the pressure-holding period at maximum load could be fitted by a general logarithmic equation.