|About this Abstract
||Materials Science & Technology 2011
||Advanced Protective Coatings for Refractory Metals and Alloys
||Coating Strategies to Improve the Oxidation Resistance of Bcc-Mo-Based Mo-Si-B Alloys
||Mufit Akinc, Matthew Kramer, Pratik Ray, Zhihong Tang
|On-Site Speaker (Planned)
Mo-based Mo-Si-B alloys have promising high temperature mechanical properties. In particular, the Mo+T2(Mo5SiB2)-based alloys have excellent resistance to fracture, with toughness values approaching 20 MPa•m½ for a continuous β-Mo matrix material. However, a fundamental limitation of these alloys is their poor oxidation resistance. A consensus is emerging to protect the Mo-based alloys with an oxidation resistant coating such as the T1-based alloy. Two different coating processes were investigated. First, the T1-based alloy was plasma-sprayed onto Mo substrates to determine the feasibility of protecting the Mo+T2(Mo5SiB2)-based alloys. The second coating strategy involved siliconizing the surface of the Mo based alloy by the halide activated pack-cementation (HAPC) process. A critical problem with coating materials is the formation of brittle intermetallic phases like the A15 during subsequent heat-treatments. Our studies on Nb and W additions indicate it might be possible to destabilize this phases in order to improve the alloys mechanical properties.
||Definite: A CD-only volume