Mechanical Properties of Fusion Welded Ceramics in the SiC-ZrB₂ and SiC-ZrB₂-ZrC Systems


Mechanical properties of welded SiC-Zr2 and SiC-Zr2-ZrC ceramics were measured up to 1700 °C. Commercial powders were hot pressed, machined into coupons, and preheated to 1600 °C before joining the ceramics using either tungsten inert gas welding or plasma arc welding. Toughness of the parent materials was 3-4 MPa*m1/2 which decreased after welding to 2-2.5 MPa*m1/2. Strength of the SiC-Zr2-ZrC parent material was ~700 MPa at 25 °C, ~300 MPa at 1700 °C, and retained 40-60% of this strength once welded. Strength of the SiC-Zr2 parent material was ~600 MPa at 25 °C and 1700 °C and retained 20-30% of this strength once welded. Griffith analysis indicated that the strength in the parent materials was controlled by the size of SiC clusters while strength of welds was controlled by the size of pores in fusion zones. Therefore, removal of pores in produced fusion zones should be investigated to improve strength of future ceramic welds.


Materials Science and Engineering

Publication Status

In Press, Corrected Proof


This work was funded by a Department of Energy phase II SBIR (DE-SC0017082) through a subcontract from UES Inc. contract #0055606U.S.

Keywords and Phrases

Borides; Carbides; Joints/Joining; Phase Equilibria; Ultra-High Temperature Ceramics

International Standard Serial Number (ISSN)

1873-619X; 0955-2219

Document Type

Article - Journal

Document Version


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© 2022 Elsevier, All rights reserved.

Publication Date

01 Jan 2022