title: Using the pressure transmission coefficient of a transmitted wave to evaluate some of the mechanical properties of refractory metals.
abstract: Refractory metals have attracted increasing interest in recent years because of their use in many high-temperature applications. However, the characteristics of these metals calculated using loaded tests (such as tensile strength tests) differ considerably from those calculated using one of the most famous methods in NDT which is called time of flying of the wave (TOF).The present study presents two solutions based on calculating the pressure transmission coefficient (PTC) of the transmitted wave between the test sample and magnesium metal. The first is based on the development of a highly accurate algorithm that lowers the cost by determining the acoustic impedance of the test specimen to calculating mechanical properties. Up to 26 theoretical tests were done (10 of these tests for refractory materials) according to their known mechanical properties to verify the accuracy of the algorithm. The convergence in results ranged from 92% to 99%. The second solution was designed to solve the same problem for specimens with a thickness of less than 1mm. Eight experimental tests were done (five using refractory materials) to verify the accuracy of the second solution, with the convergence in the results ranging from 94% to 97%. The relationships of the Vrms measured from the oscilloscope with the PTC and with the Fourier transform spectrum were derived. The results of this research were closer to the standard mechanical properties for refractory metals compared with several recent acoustic tests.
authors.affiliation: Electronic Department, College of Engineering, Diyala University, Iraq; Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, University Kebangsaan Malaysia, UKM, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia. Electronic address: arshad_ald@yahoo.com.
authors.forename: Arshed Abdulhamed
authors.initials: AA
authors.lastname: Mohammed
authors.affiliation: Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, University Kebangsaan Malaysia, UKM, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia.
authors.forename: Sallehuddin Mohamed
authors.initials: SM
authors.lastname: Haris
authors.affiliation: Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, University Kebangsaan Malaysia, UKM, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia.
authors.forename: Mohd Zaki
authors.initials: MZ
authors.lastname: Nuawi
keywords: Elastic modulus; Pressure transmission coefficient; Refractory metals and their alloys