Low Temperature Elastic Properties of Aluminum 5083-0 and Four Ferritic Nickel Steels

The low-temperature elastic properties have been determined for five commercial alloys that have possible structural applications at cryogenic temperatures. The alloys are 5083-0 aluminum and four ferritic steels: 3.5, 5, 6, and 9 percent nickel. An ultrasonic (10 MHz) pulse-superposition method was used to measure longitudinal and transverse wave velocities. Using the velocities and the mass density as input, the following elastic constants were calculated: longitudinal modulus, Young's (tensile) modulus, shear (rigidity) modulus, bulk modulus (reciprocal compressibility), and Poisson's ratio. Measurements were made semicontinuously from 300 to 4K. The room-temperature composition dependence of iron-nickel alloys is reviewed comprehensively up to 12 percent nickel. Debye temperatures were calculated from the elastic constants. A discussion is given of the temperature dependences of the elastic constants and differential relationships among the elastic constants.