High gage factor strain gage
A metal resistance strain gage with a high gage factor is provided. The electrical resistance strain gage includes a strain sensitive metallic element and has a chemical composition on a weight basis of approximately 63% to 84% Ni and approximately 16% to 37% Fe and a gage factor greater than 5.
1. An electrical resistance strain gage comprising:
a strain sensitive metallic element having a chemical composition on a weight basis of approximately 63% to 84% nickel and approximately 16% to 37% iron and a gage factor of at least 5.
2. The strain gage of claim 1 , wherein the strain sensitive metallic element further comprises metallic alloying additions in an amount that is less than about 10% of the chemical composition of the strain sensitive metallic element on a weight basis.
3. The strain gage of claim 2 , wherein the alloying addition is manganese.
4. The strain gage of claim 3 , wherein the manganese comprises about 1% to 5% of the alloy on a weight basis.
5. The strain gage of claim 2 , wherein the alloying addition is tungsten.
6. The strain gage of claim 5 , wherein the tungsten comprises about 0.5% to about 2% of the alloy on a weight basis.
7. The strain gage of claim 2 , wherein the alloying addition is molybdenum.
8. The strain gage of claim 7 , wherein the molybdenum comprises about 1% to about 5% of the alloy on a weight basis.
9. The strain gage of claim 2 , wherein the alloying addition is chromium.
10. The strain gage of claim 9 , wherein the chromium comprises about 1% to about 5% of the alloy on a weight basis.
11. The strain gage of claim 2 , wherein the strain sensitive metallic element is a wire.
12. The strain gage of claim 11 , wherein the wire is configured in a serpentine pattern.
13. The strain gage of claim 2 , wherein the strain sensitive metallic element is a foil.
14. The strain gage of claim 13 , wherein the foil is configured in a serpentine pattern.
15. The strain gage of claim 2 , wherein the strain sensitive metallic element is a thin film.
16. The strain gage of claim 15 , wherein the thin film is configured in a serpentine pattern.
17. The strain gage of claim 1 , wherein the strain sensitive metallic element is a wire.
18. The strain gage of claim 17 , wherein the wire is configured in a serpentine pattern.
19. The strain gage of claim 1 , wherein the strain sensitive metallic element is a foil.
20. The strain gage of claim 19 , wherein the foil is configured in a serpentine pattern.
21. The strain gage of claim 1 , wherein the strain sensitive metallic element is a thin film.
22. The strain gage of claim 21 , wherein the thin film is configured in a serpentine pattern.
23. The strain gage of claim 1 , wherein the strain sensitive metallic element is cold rolled and annealed to achieve the gage factor of at least 5 .
24. An electrical resistance strain gage comprising:
a strain sensitive metallic element having a chemical composition on a weight basis of approximately 63% to 84% nickel, approximately 16% to 37% iron, and an alloying addition that is present in an amount no greater than 10% of the chemical composition of the strain sensitive metallic element on a weight basis and is selected from the group consisting of manganese, tungsten, molybdenum, chromium, and combinations thereof, with a gage factor of at least 5.
25. The strain gagc of claim 1 An electrical resistance strain gage comprising:
a strain sensitive metallic element having a chemical composition on a weight basis of approximately 63% to 84% nickel and approximately 16% to 37% iron and a gage factor of at least 5, wherein the material of the strain sensitive metallic element forms a face-centered-cubic crystal lattice with nickel atoms occupying face positions and iron atoms occupying corner positions.