Structural Engineering and Mechanics, Vol. 54, No. 6 (2015) 1075-1095 DOI: http://dx.doi.org/10.12989/sem.2015.54.6.1075 1075 Copyright © 2015 Techno-Press, Ltd. http://www.techno-press.org/?journal=sem&subpage=8 ISSN: 1225-4568 (Print), 1598-6217 (Online) A review of the application of acoustic emission technique in engineering S. Gholizadeh  , Z. Leman a and B.T.H.T. Baharudin b Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia (Received September 30, 2014, Revised February 19, 2015, Accepted February 23, 2015) Abstract. The use of acoustic emission (AE) technique for detecting and monitoring damages and the progress on damages in different structures is widely used and has earned a reputation as one of the most reliable and well-established technique in non-destructive testing (NDT). Acoustic Emission is a very efficient and effective technology used for fracture behavior and fatigue detection in metals, fiberglass, wood, composites, ceramics, concrete and plastics. It can also be used for detecting faults and pressure leaks in vessels, tanks, pipes, as well as for monitoring the progression of corrosion in welding. This paper reviews major research developments over the past few years in application of acoustic emission in numerous engineering fields, including manufacturing, civil, aerospace and material engineering. Keywords: application of AE; acoustic emission; non-destructive testing; NDT applications 1. Introduction Acoustic emission is one of the new introductions to the Non-Destructive Evaluation (NDE) industry. It was introduced to address the limitations of previous NDE technologies on applications or to cut down financial costs of evaluation. The need to evaluate AE‟s suitability for use in engineering applications was instigated by some new groups of researchers from Japan, Europe and the USA in the late 1970s and early 1980s (Barber 2006). The definition of AE as given by ASTM E1316 (2014) is “The class of phenomena whereby transient elastic waves are generated by the rapid release of energy from a localized source or sources within a material, or the transient wave(s) so generated”. Acoustic emission or stress wave emission as it is often called describes the acoustic stress waves that emerged as a result of a rapid release of energy because of the microstructural changes that occur in materials (Musa 2002). AE is a very efficient and effective technology used for fracture behavior and fatigue detection in metals, fiberglass, wood, composites, ceramics, concrete and plastics (Huang et al. 1998). It can also be used for detecting faults and pressure leaks in vessels, tanks, pipes, as well as for Corresponding author, Msc. Student, E-mail: vsco_gh@yahoo.com a Ph.D., E-mail: zleman@upm.edu.my b Ph.D., E-mail: hangtuah@upm.edu.my