Mechanical Behavior and Applications of Plasma Arc Welded Ceramics

Author

Derek S. King
Greg Hilmas, Missouri University of Science and TechnologyFollow
William Fahrenholtz, Missouri University of Science and TechnologyFollow

Abstract

Zirconium diboride and zirconium carbide-based ceramics were joined by plasma arc welding to demonstrate the versatility of this technique. A parent material composition consisting of ZrB₂ with 20 vol% ZrC was hot pressed to near full density, sectioned to produce specimens for welding, and welded together to produce billets for mechanical property studies. The four-point flexure strength of the parent material was~660 MPa, while the strength of the welded specimens ranged from~140 to~250 MPa. Microstructural analysis revealed that decreased strength in the welded specimens was caused by volume flaws, microcracking of large ZrB₂ grains (up to 1 mm in length), and residual tensile stresses that developed at the surface of weld pools during cooling. The versatility of plasma arc welding was demonstrated by joining of ZrC-based ceramics and fabricating three ZrB₂-ZrC components for potential applications, including a high-temperature electrical contact, an ultra-high-temperature thermocouple, and a wedge that was a notional wing leading edge. These three applications demonstrated the ability to join ceramics to a refractory metal, fabricate a chemically inert high-temperature thermocouple, and produce complex shapes for aerospace applications.

Recommended Citation

D. S. King et al., "Mechanical Behavior and Applications of Plasma Arc Welded Ceramics," International Journal of Applied Ceramic Technology, vol. 13, no. 1, pp. 41 - 49, Blackwell Publishing Ltd, Jan 2016.

The definitive version is available at https://doi.org/10.1111/ijac.12402

Department(s)

Materials Science and Engineering

Keywords and Phrases

Aerospace applications; Carbides; Ceramic materials; Electric arc welding; High temperature applications; Mechanical properties; Plasma welding; Refractory metals; Strength of materials; Thermocouples; Welding; Zirconium compounds

International Standard Serial Number (ISSN)

1546-542X

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2016 Blackwell Publishing Ltd, All rights reserved.

Publication Date

01 Jan 2016