1. Solidification Analysis of a High Cr-Ni Heat-Resistant Alloy: Microstructure and Hardness Evaluation
- Author
-
Wellington Anjos da Silva, Sarah Maria de Albuquerque Sousa, and José Eduardo Spinelli
- Subjects
Heat resistant alloy ,SDAS ,microstructure ,hardness ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Ni-Cr-based alloys are known for their high resistances to corrosive environments, high temperatures, and stresses, finding wide application in furnace systems in petrochemical plants. However, very few is known about their solidification features and how they can impact processing and properties. This study investigated the alloy solidification, obtaining a variety of as-cast microstructures in the high-Cr 28Cr48Ni5W3Co14Fe alloy. It presents results of optical, hardness, and CALPHAD analyses in a straightforward examination of solidification according to the application in the cast condition. The directional solidification setup allowed to assess a variety of samples solidified at different cooling rates, and showing different microstructural coarsening. The analyses determined secondary dendritic arm spacings (SDAS) ranging from 16 μm to 120 mm. It was determined the formation of the FCC+M23C6 quasi-eutectic constituent filling the interdendritic. An effective correlation was chosen to compute the corresponding cooling rates. Finally, an in-depth applied analysis of tube-support components for pyrolysis through cast simulation revealed the SDAS variation to be a critical feature in pre-programming casting designs. These findings play a fundamental role in advancing cast operations of heat-resistant alloy components, enhancing both quality and processing setups.
- Published
- 2024
- Full Text
- View/download PDF