Nonlinear ultrasonic heat treatment process evaluation and optimization method and device

Abstract

The invention discloses a nonlinear ultrasonic heat treatment process evaluation and optimization method and device. The method comprises the following steps: acquiring an ultrasonic baseband signal A1 propagated in a test piece and amplitude A2 of second harmonics, and calculating a nonlinear acoustic parameter beta' of the test piece, wherein the expression is as shown in the specification; and comparing the difference between nonlinear acoustic parameters of an untreated material and a material subjected to different heat treatment processes based on the obtained relative nonlinear acoustic parameter beta'. The better the heat treatment process is, the more uniform the interior structure of the material subjected to heat treatment is, the performance is greatly improved, and the acoustic nonlinear response of ultrasonic propagation is low. The microstructure of the material can be changed based on heat treatment, a direct correlation exists between the nonlinear response of ultrasonic propagation and the microstructure of the material. According to the method, the heat treatment process effects can be nondestructively, rapidly and effectively evaluated, and the related parameters of heat treatment process are optimized and perfected.

Description

technical field [0001] The invention discloses a method and device for nonlinear ultrasonic evaluation and optimization of a heat treatment process, belongs to the technical field of material testing according to the International Patent Classification (IPC), and specifically relates to the technology of non-destructive evaluation and characterization of material properties. Background technique [0002] The materials used in key engineering structural parts usually need to undergo a heat treatment process to improve their mechanical properties before they are officially put into use, so as to meet the load-bearing requirements of engineering structures. The reason why heat treatment can improve the material properties is mainly because it changes the microstructure of the material (ie, homogeneous slip and local plastic deformation parallel to the interface). Heat treatment process parameters directly affect the effect of heat treatment process, and then have a key impact o...

AI Technical Summary

Problems solved by technology

The commonly used ultrasonic evaluation and detection method is to characterize the material structure and mechanical properties by using ultrasonic linear physical parameters (such as sound velocity, amplitude, and attenuation coefficient). When applied to the optimization evaluation of heat treatment process parameters, the ideal effect cannot be achieved. For example, when the difference of several heat treatment parameters is small, the linear ultrasonic method cannot clearly distinguish their advantages and disadvantages.

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