Biography
Prof. Ji Wang
Prof. Ji Wang
Ningbo University, China
Title: A Quantitative Characterization and Assessment of Surface Roughness of Structural Components from the Measurement of Wave Velocities
Abstract: 
The surface of materials of commonly used structural components of various functions is processed with many technologies and subjected to change under the attack of many factors in service such as corrosion, friction, and impact. With safety and reliability concerns, it is always beneficial to have the surface and immediate vicinity characterized with the use of mechanical properties and other factors such as bonding rigidity and surface roughness. Among many techniques for the measurement and assessment, methods based on nondestructive testing technology such as acoustic waves are always preferred for the advantages such as in-situ, fast, and noncontact features. To improve such measurement, we consider a component with rough surface for the acoustic wave properties in relation to changes of material properties. By calculating the velocity of surface acoustic waves with the consideration of material properties and surface roughness, more accurate properties of the surface layer are obtained to enable accurate estimation as part of the characterization and assessment procedure. Further improvement will be the consideration of the grading materials. It is believed such analysis will lead to possible novel approaches for the assessment of the surface of components of various functions. Such a method can be used for the measurement of visible and nonvisible material surface with known properties for an enhanced assessment of the component to satisfy engineering applications needs.
Biography: 
Professor Ji Wang has been a Qianjiang Fellow Professor of Zhejiang Province at Ningbo University since 2002. He also served as Associate Dean for Research and Graduate, School of Mechanical Engineering and Mechanics, Ningbo University, from 2013 to 2019. Professor Ji Wang is the founding director of the Piezoelectric Device Laboratory, which is a designated Key Laboratory of City of Ningbo. Professor Ji Wang was employed at SaRonix, Menlo Park, CA, as a senior engineer from 2001 to 2002; NetFront Communications, Sunnyvale, CA, as senior engineer and manager from 1999 to 2001; Epson Palo Alto Laboratory, Palo Alto, CA, as Senior Member of Technical Staff from 1995 to 1999. Professor Ji Wang also held visiting positions at Chiba University, University of Nebraska-Lincoln, and Argonne National Laboratory. He received his PhD and Master degrees from Princeton University in 1996 and 1993 and bachelor from Gansu University of Technology in 1983.

Professor Wang has been working on acoustic waves and high frequency vibrations of elastic and piezoelectric solids for resonator design and analysis with several US and Chinese patents, over 120 journal papers, and frequent invited, keynote, and plenary presentations in major conferences around world. He has been board members, advisors, and consultants to many leading companies in acoustic wave device industry. Professor Wang has been a member of many international conference committees and currently serving the IEEE UFFC Technical Program Committees of the Frequency Control and Ultrasonics Symposia, the IEEE MTT-S, and the IEC TC-49. He is also the funding chair of Committee on Mechanics of Electronic and Magnetic Devices, CSTAM, and the SPAWDA. From 2015, Profess Wang is the editor-in-chief of Structural Longevity and members of the editorial boards of several international journals.