材料力学性能退化的超声无损检测与评价

ADVANCES IN NONDESTRUCTIVE TEST AND EVALUATION OF MATERIAL DEGRADATION USING NONLINEAR ULTRASOUND

材料性能退化总是伴随着某种形式的材料非线性力学行为,从而引起超声波传播的非线性,即高频谐波的产生.基于此,材料和结构的超声无损检测与主人技术发展成起来.首先介绍固体介质内的非线性超声波动方程的基础,并综述了利用超声波传播的非线性特性对结构材料和粘结面的力学性能退化进行无损检测与评价的研究进展.之后对材料在疲劳、拉伸以及蠕变载荷作用下,其力学性能退化进行超声无损检测与评价的试验研究进行了介绍;综述了超声波传播非线性的机理研究,以及利用超声波对粘结面的粘结强度及其力学性能退化评估所开展的研究.最后指出了今后该领域需要进一步研究的问题.

Material degradation is usually preceded by some kind of nonlinear mechanical behavior before significant plastic deformation or material damage occurs. When an ultrasonic wave propagates through the material at this stage, a strong nonlinear effect will be generated and thus higher harmonics will be produced due to the nonlinear elastic properties of that material. In this paper, advances in experimental and theoretical studies of nondestructive test and evaluation (NDT and NDE) of material degradation under fatigue, tension and creep loads using nonlinear ultrasonic waves were reviewed, including advances in experimental and theoretical studies of NDT and NDE of bond strength and mechanical degradation of adhesive joints. Also, further studies in the field of NDT and NDE using nonlinear ultrasound were suggested.