|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Refractory Metals 2018
||Assessments of the Mo-Si-X-(B) System for High Temperature Structural Application Potentials
||Young-Won Kim, Sang-Lan Kim
|On-Site Speaker (Planned)
Select Mo-Si-X-(B) alloys have been considered to possess high temperature (>1000°C) structural application potentials in terms of their excellent oxidation resistance and good mechanical behavior. Their realization has been hindered by several critical barriers: 1) poor oxidation resistance at low temperatures (600-900°C); 2) zero tensile plasticity up to BDTTs, 3) poor processing responses making the use of fine microstructures inevitable; and 4) consequently further lowered BDTTs (<1100°C), above which creep strength is low for the requirements. The last three barriers are evaluated for the upper service temperature limits. Low temperature surface degradation is discussed with new data and detailed observations, along with the process that helps reduce the oxygen-surface interaction. This process involves preforming a high temperature glass layer containing finely dispersed Mo-rich particles that can be persistent at all temperatures due to the increased viscosity. Realistic approaches are proposed to redefine the scope and directions of future RD activities.
||Planned: Supplemental Proceedings volume