Mechanical Behavior and Applications of Plasma Arc Welded Ceramics
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.
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 http://dx.doi.org/10.1111/ijac.12402
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)
Article - Journal
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