Microstructural evolution and 1500 °C oxidation resistance of Mo(Al,Si)2 fabricated via an innovative two-step SHS-SPS technique

Microstructural evolution and 1500 °C oxidation resistance of Mo(Al,Si)2 fabricated via an innovative two-step SHS-SPS technique

An innovative two-step approach of self-propagating high-temperature synthesis (SHS) and spark plasma sintering (SPS) was developed to rapidly fabricate MoSi2 and Mo(Al,Si)2 ceramics for high-temperature anti-oxidation applications. The SHS process predominantly promoted the synthesis of high-purity...

Full description

Saved in:
Bibliographic Details
Main Authors: Nana Zhu, Lu Zhu, Baojing Zhang, Peizhong Feng, Shiheng Li, Philipp V. Kiryukhantsev-Korneev, Evgeny A. Levashov, Xuanru Ren, Xiaohong Wang
Format: Article
Language:English
Published: Elsevier 2024-11-01
Series:Materials & Design
Subjects:
Two-step technique
MoSi2
Al-alloyed ceramics
Microstructural evolution
High-temperature oxidation
Online Access:http://www.sciencedirect.com/science/article/pii/S026412752400772X
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:An innovative two-step approach of self-propagating high-temperature synthesis (SHS) and spark plasma sintering (SPS) was developed to rapidly fabricate MoSi2 and Mo(Al,Si)2 ceramics for high-temperature anti-oxidation applications. The SHS process predominantly promoted the synthesis of high-purity and high-yield MoSi2 and Mo(Si,Al)2 phases in the alloyed powders. Subsequently, dense and crack-free MoSi2 and Mo(Al,Si)2 ceramics were produced using SPS. 1500 °C oxidation tests of the ceramics (100 h) revealed the formation of a protective SiO2 oxide layer on the surface of MoSi2 ceramics, while an Al-Si-O composite glassy oxide layer formed on Mo(Si,Al)2 ceramics, which exhibited better thermal stability and lower oxygen permeability compared to the single SiO2 oxide layer. However, an excessive Al content (>0.05 at.%) compromised the oxidation resistance due to the emergence of a Si-depleted Mo5(Si,Al)3 layer with inferior oxidation resistance, which was caused by the high-temperature diffusion of Si. Therefore, via this novel two-step SHS-SPS technique compact and crack-free Mo(Si,Al)2 ceramics can be rapidly synthesized at high temperatures. When trace amount of Al was added (0.05 at.%), Mo(Si0.95Al0.05)2 showed optimum high-temperature oxidation resistance.
ISSN:0264-1275

Similar Items