Manganin sensors as low temperature pressure gauges

Abstract

The pressure coefficient of the resistance of manganin sensors was studied in the temperature range 55K-350K. A He-gas pressure system was used to maintain fully hydrostatic conditions at low temperatures. The pressure coefficient was determined from isothermal pressure dependencies of resistance measured at various fixed temperatures. The obtained results were verified by isobaric measurements carried out as a function of temperatures at several fixed pressures. The pressure coefficient has a minimum at 114K, about 5% lower than the room temperature value. Below and above 114K it can be well approximated by linear dependences: α(T)/α(298K) = 0.9913- 3.35543 × 10⁻⁴ and 0.9208 + 2.2623 × 10⁻⁴ T, respectively.

Key Words:

• Pressure sensor
• manganin
• pressure coefficient