Application of the strain gauge method to thermal expansion measurement under high pressure and high magnetic field

摘要

The influence of pressure and magnetic field on strain gauge (SG) has been investigated in order to clarify the behaviors of SG under these conditions. It is found that the electrical resistance of SG mounted on Cu changes largely above a critical pressure P{sub}c at which the pressure transmitting medium is frozen due to solidification. However, no significant change in electrical resistance of SG above P{sub}c was observed for that on WC and Mo. The magnetoresistance of SG at 4.2 K shows ahysteresis between an increasing and decreasing magnetic field at ambient pressure, which is suppressed by an application of pressure. On the basis of these data, a suitable reference and the relationship between the arrangement of SG and direction ofload are briefly discussed.