A method is disclosed for detecting the T1 phase in aluminum-lithium alloys through simultaneous measurement of conductivity and hardness. In employing eddy current to measure conductivity, when the eddy current decreases with aging of the alloy, while the hardness of the material continues to increase, the presence of the T1 phase may be detected.
US 4,947,117 A
Iowa State University Research Foundation, Inc.
Buck, Otto; Bracci, David J.; Jiles, David C.; Brasche, Lisa H.; Shield, Jeffrey E.; and Chumbley, L. Scott, "Nondestructive detection of an undesirable metallic phase, T1, during processing of aluminum-lithium alloys" (1990). Iowa State University Patents. 253.