Technical parameters:

Ni(core wire): 41-43%

Cu: 21-30%

Tensile strength: Less than or equal to 65 kilograms per square millimeter

Extensibility: More than 20%

Coefficient of expansion:

Radial: From 82 to 92 multiplied by seven of the 10 negative side centimeters per centimeter per degree

Axial: From 62 to 65 multiplied by seven of the 10 negative side centimeters per centimeter per degree