An Acoustic Method for Evaluating the Quality of Thermal Processing of 44NKhTYu Alloy

Abstract

A homogeneous fine-grained structure that provides required strength characteristics has been shown to form in the (44NKhTYu alloy) elinvar for the considered thermal processing mode. Experimental data are provided that demonstrate elasticity characteristics to remain constant within a temperature range from–70 to +70°С. The persistence of the propagation velocities of elastic waves in this temperature range makes it possible to use this regularity in the development of techniques for thermal-processing quality evaluation. The ratio of the velocities of longitudinal and shear elastic waves has been proposed as a “diagnostic parameter.” The possibility has been studied for using elastic waves to inspect 44NKhTYu-alloy characteristics after various thermal-processing modes.