Intelligent Sensing and Actuation using Novel SMA Materials

点击翻译按钮获取中文摘要

This project was originally initiated as the Monbusho Grant-in-Aid for International Scientific Research: University-to-University Cooperative Research, and then it was shifted to the JSPS Grant-in-Aid for Scientific Research (B) (2). Hence the project was jointly performed by Tohoku University group and Moscow State University researchers by inviting them to Tohoku University. Based on this joint research the following achievements were obtained.1.Shape memory effect and electromagnetic properties of ferromagnetic shape memory alloy Ni_2MnGa.(1)Peculiar magnetic properties were measured in the experiment. We clarified the temperature hysteresis of Curie temperature, and the peculiarities due to meta ferromagnetism by magnetization measurement under constant temperatures.(2)We proposed two mechanism for the explanation of the magnetic field induced strains and interpreted the strains in Ni_2MnGa, FePd and FePt alloys.(3)Polycrystalline bulk samples were fabricated by arc melting method and pulse discharge sintering (PDS) method. The materials made by PDS show better mechanical properties but less magnetic field induced strains. A single crystal bulk sample Ni_<2.08>Mn_<0.98>Ga_<0.94> exhibits giant magnetostrain over 1.0%.2.CVD diamond-like carbon (DLC) film(1)In order to make novel functional materials with SMA and DLC, a CVD equipment was newly designed and fabricated.(2)DLC with metal nanocluseters was coated on the substrates. Temperature dependency of resistivity was measured to verify the possibility of temperature sensors. We fabricated a first step demonstrator of temperature sensors using Cr contained Me-DLC.