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Inhibición del deslizamiento en aleaciones nanograneadas con redes de límites de grano estables
B B Zhang1, Y G Tang1,2, Q S Mei3
1Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
Science (New York, N.Y.)
|November 10, 2022
Resumen
Los investigadores desarrollaron un método novedoso para evitar el deslizamiento a alta temperatura mediante la creación de redes estables de límites de grano (GB) en aleaciones nanograneadas. Este enfoque mejora significativamente la resistencia al deslizamiento, superando las superaleaciones convencionales.
Área de la Ciencia:
- Ciencias de los materiales
- Ingeniería mecánica
- Trabajos de metalurgia
Sus antecedentes:
- El flujo de alta temperatura causa fallas en los componentes.
- Los límites de grano (GB) suelen acelerar el deslizamiento.
- La eliminación de GB es una estrategia común para mejorar la resistencia a la insistencia.
Objetivo del estudio:
- Investigar una nueva estrategia para inhibir el creep utilizando redes GB estables.
- Para explorar el potencial de las aleaciones nanograinadas para una resistencia superior al deslizamiento.
Principales métodos:
- Fabricación de aleaciones monofásicas de níquel-cobalto-cromo con nanopartículas.
- Inducción de deformación plástica para crear redes GB estables entrelazadas con límites gemelos.
- Prueba de las velocidades de desplazamiento bajo tensión gigapascal a 700°C.
Principales resultados:
- Las redes GB estables inhibían efectivamente los procesos de arrastre difusional.
- Se ha logrado una resistencia sin precedentes con velocidades de ~10^-7 por segundo.
- La aleación nanoestructurada superó a las superaleaciones convencionales en resistencia al deslizamiento.
Conclusiones:
- Las redes GB estables ofrecen una alternativa viable a la eliminación de GB para la resistencia al deslizamiento a altas temperaturas.
- Las aleaciones nanoestructuradas con redes GB diseñadas muestran un rendimiento excepcional.
- Esta estrategia es prometedora para el desarrollo de materiales avanzados para aplicaciones a altas temperaturas.
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