Research Seminar of Prof. TIEN-CHIEN JEN from University of Johannesburg

Lecture Time: 10:00 on 10th November, 2015

Lecture Room: C501 of National Sicence Park

Lecture Title: Cold Gas Dynamic Spraying for micro and nano-size particles and its applications

TIEN-CHIEN JEN

ASME Fellow

Professor, Mechanical Engineering Science

University of Johannesburg, South Africa

Tel: US: 414-336-0378

South Africa: +27 11 5594208

Email:tienchienjen@gmail.com

tjen@uj.ca.za

Google Scholar:https://scholar.google.co.za/citations?hl=en&user=Q-vedboAAAAJ

Abstract:

The Cold Gas Dynamics Spraying (CGDS) deposition process is an emerging technology for coating surfaces and consolidation of powder. The process is based on the impact on and the subsequent adherence to a substrate of particles of high kinetic energy. Current CGDS involves injecting microscopic powdered particles of a metal or another solid into a supersonic jet of rapidly expanding gas and then shooting them at a target surface. The process is performed in order to directly bond powder with the substrate through high-speed impact.In contrast to well-known thermal spray processes, the cold spray particles (metals, polymers) never become melted throughout the whole process. Low deposition temperatures offer several advantages over other thermal spraying and plasma spray particles techniques, including no phase transformations, little or no oxidation, no evaporation, no substrate melting and no recrystallization. In addition, the residual stresses and deformation induced by the mismatch between the thermal expansion coefficients of the coating and the substrate are minimized. Furthermore, the process is inherently safer than thermal spray methods because there are no molten materials. The CGDS coating process requires less capital investment and less space than conventional thermal spray methods. The powders (fall off from the substrate) can even be recycled to improve the economics of the process.

Biography:

Education:

Jan. 1988-March 1993: Ph.D., Mechanical and Aerospace Engineering, University of California, Los Angeles

Sept. 1985-June 1987: M.S., Power Mechanical Engineering, National Tsing-Hua University, Hsinchu, Taiwan

Sept. 1978-June 1982: B.S., Naval Architecture and Marine Engineering, National Cheng-Kung University, Tainan, Taiwan

Positions Held:

July 2015-present: Professor, Department of Mechanical Engineering Science, University of Johannesburg, South Africa

August 2013-June 2015: Adjunct Professor, University of Wisconsin, Milwaukee

May 2013-May 2014: Dean, College of Engineering, UAA

Oct. 2010-Sep 2012: Interim Dean, College of Engineering and Applied Science, UWM

July 2008-May 2013: Professor, University of Wisconsin, Milwaukee

July 2005-June 2010: Chairman, Mechanical Engineering Department

Aug. 2001-June 2008: Associate Professor, University of Wisconsin, Milwaukee

Aug. 1997-July 2001: Assistant Professor, University of Wisconsin, Milwaukee

Aug. 1996-Aug. 1997: Visiting Assistant Professor, Oakland University, Rochester, Michigan

Apr. 1993-July 1996: Assistant Research Engineer, General Motors and Mechanical and Aerospace Engineering, University of California, Los Angeles

Jan. 1988-March 1993: Research Assistant, University of California, Los Angeles

Sept. 1985-June 1987: Research Assistant, National Tsing-Hua University, Hsin-chu, Taiwan

Publications:

Professor Jen has written a total of 173 peer-reviewed papers including 80 peer-reviewed journal papers, published in many prestigious journals including International Journal of Heat and Mass Transfer, ASME Journal of Heat Transfer, ASME Journal of Mechanical Design and ASME Journal of Manufacturing Science and Engineering. He also has written five chapter papers including a chapter in Numerical Simulation Proton Exchange Membrane Fuel Cell, published by WIT Press, and another chapter in Application of Lattice Boltzmann Method in Fluid Flow and Heat Transfer in Computational Fluid Dynamics - Technology and Application, and more.

Patents:

Professor Jen has applied for two Chinese patents (2013104728193 and 2013104728371), and other two inventions that have been revealed TTO (Technology Transfer Office, University of Johannesburg) are pending (2015).

Special Honors and Awards:

Elected to the status of American Society of Mechanical Engineer Fellow in recognizing the contribution to Mechanical Engineering, October 2011

Appointed as Guest Professor of Chongqing University, China, in recognition of significant research achievement, October 2009

Appointed as Guest Professor of Anhui Agriculture University, China, in recognition of significant research achievement, October 2009

Appointed as Guest Professor of Shangdong University, China, in recognition of significant research achievement, October 2010

CEAS Million Dollars Research Funding Club, in recognition of significant funding received, September 2008

Graduate School/UWM Foundation Outstanding Research Award, in recognition of Outstanding and Creative Activity, November 2000

NSF GOALI Award, the first award of its kind ever awarded to UWM by NSF, 1999 – 2006

Outstanding Research Award, CEAS, UWM, 2001

SME Research Initiation Award, SME Education Foundation, 1998 – 1999

SME Research Initiation Award, SME Education Foundation, 1997 – 1998

Best Paper Award, CIRP Annals, titled “Thermal Aspects of Grinding with CBN Wheels,” CIRP Annals, Vol. 38, No. 1, pp.557 – 560

Listed in Marquis Who’s Who in Science and Engineering (1994 – to date)

Listed in Marquis Who’s Who in the World (1994 – to date)

Listed in Marquis Who’s Who in America (1995 – to date)

Listed in Lexington Who’s Who (1999 – to date)