DEVELOPMENT OF RESISTANCE STRAIN GAGES USABLE UP TO 1600 F
Abstract
To measure stresses produced in aircraft structures by aerodynamic heating, a quasi-static high temperature strain gage is required which exhibits good stability characteristics. In the present application it was desired to measure large strains in the temperature range 1000 to 1600 F. Refractory single phase alloys with Fe, Co, and Ni bases were selected for exploration as strain gage wires. Besides good oxidation resistance it was aimed to achieve a low temperature coefficient of resistance and matching expansivity with the chosen base material. The solid solution alloys of the Fe-Cr-Al composition approached most closely the ideal requirements for high temperature strain gage wires. Several alloys in this group were vacuum melted and the hot and cold forming properties were determined. Fe25 Cr-5 Al, Fe-25 Cr-7.5 Al, and Fe-20 Cr-10 Al alloys ultimately were drawn into 0.001 to 0.002in.-diam wires. Strain gages fabricated from these wires were cemented to Inconel test bars and preliminary gage calibrations were made at elevated temperatures. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 23, 1962
- Accession Number
- AD0273322
Entities
People
- G. Stevens
- J.p. Sheehan
Organizations
- IIT Research Institute