Ultrasonic Measurement of Residual Stress in SMAT Metals

Document Number: 2006-01-0320

Date Published: April 2006

Author(s):
Xiaolai Zhou - Ultra RS
Farid Belahcene - Ultra RS
Fabien Thomas - Ultra RS
Jian Lu - The Hong Kong Polytechnic Univ.

Abstract:
Surface mechanical attrition treatment (SMAT) consists of producing a thin surface layer of compressive residual stresses that prevents crack initiation and retards crack growth during service. The capability for a nondestructive measurement of the compressive stresses is very useful to assure fatigue life of components treated by SMAT in the industrial domain. In this paper, an ultrasonic method based on the longitudinal critically refracted (Lcr) wave is proposed for this purpose. The Lcr wave travels just below the surface of the material, so it may be used to detect subsurface stresses in the structure components. This wave has several advantages over conventional surface waves and bulk waves in detecting the residual stress. The Lcr technique has been applied on the SMAT aluminum alloy specimen to determine the residual stresses in different depths, as well as on the specimens before and after stress relaxation annealing treatment in different zones. The experimental results show that this Lcr technique is feasible for the evaluation of residual stresses and control of the state of the material during mechanical treatment.

Product Status: In Stock

Included in: V115-5

See other papers presented at SAE 2006 World Congress & Exhibition, April 2006, Detroit, MI, USA, Session: Experiments in Automotive Engineering (Part 2 of 6) - Residual Stress Measurement and Applications

Purchase more technical papers and save! With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay. Learn more >