Mechanical Behavior and Applications of Plasma Arc Welded Ceramics

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.

Document Details

Document Type
Pub Defense Publication
Publication Date
May 06, 2015
Source ID
10.1111/ijac.12402

Entities

People

  • Derek S. King
  • Greg Hilmas
  • William G. Fahrenholtz

Organizations

  • Air Force Office of Scientific Research
  • Missouri University of Science and Technology

Tags

Fields of Study

  • Materials science

Readers

  • Metallurgy
  • Reinforced Composite Materials
  • Surface Engineering/Surface Coating Technology.

Technology Areas

  • Space