FeCrAl coating for high-temperature low-cycle fatigue resistance on surface of T91 steel and preparation method thereof
By optimizing the composition and preparation method of the FeCrAl coating, controlling the Al content and coating thickness, the mechanical mismatch between the coating and the T91 steel substrate was solved, thereby improving the high-temperature and low-cycle fatigue performance and corrosion protection effect of T91 steel.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TIANJIN UNIV
- Filing Date
- 2026-05-19
- Publication Date
- 2026-07-17
AI Technical Summary
The existing FeCrAl coating on T91 steel has a high Al content, which leads to a mismatch in mechanical properties, resulting in uncoordinated interfacial strain, increased fatigue crack initiation and propagation speed, and reduced material life.
By controlling the Al content to be 5-6 wt.% and the Cr content to be 12-14 wt.%, and using atmospheric plasma spraying to prepare the FeCrAl coating, combined with chemical electropolishing and sandblasting pretreatment, and then remelting and mechanical grinding after spraying, the coating thickness was optimized to 15-40 μm, thus achieving mechanical matching between the coating and the T91 steel substrate.
It improves the fatigue life of the coating under high temperature and low cycle fatigue conditions, shifts the crack initiation location from the interface to the coating surface, and the crack propagation stage within the coating accounts for 50-70% of the total life. It effectively blocks liquid lead and bismuth corrosion and improves the fatigue life by more than 2 times.
Smart Images
Figure CN122406137A_ABST