The Mechanism of η Phase Precipitation in A286 Superalloy During Heat Treatment
| Autor: | Masumeh Seifollahi, S. H. Razavi, Seyed Mahdi Abbasi, Sh. Kheirandish |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Materials science
Precipitation (chemistry) Scanning electron microscope Mechanical Engineering Metallurgy Analytical chemistry Atmospheric temperature range law.invention Superalloy Optical microscope Mechanics of Materials law Differential thermal analysis Phase (matter) Volume fraction General Materials Science |
| Zdroj: | Journal of Materials Engineering and Performance. 22:3063-3069 |
| ISSN: | 1544-1024 1059-9495 |
| DOI: | 10.1007/s11665-013-0592-1 |
| Popis: | In this research, the mechanism of eta (η-Ni3Ti) phase precipitation in iron-nickel-based A286 superalloy was assessed during aging heat treatment in the temperature range between 650 and 900 °C for the times of 1-30 h. Optical microscopy, scanning electron microscopy, differential thermal analysis, and x-ray diffractometry were used to describe the η phase transformation. The results showed that the major precipitates at temperatures below 840 °C were γ′ and η. The η phase started to precipitate at the expense of the γ′ phase after prolonged aging. The η phase existed in the samples aged at temperature higher than 760 °C with cellular morphology. The η volume fraction increased with increasing heat treatment time. In addition, when the aging temperature was increased from 760 to 820 °C, the η volume fraction increased and then decreased after 840 °C. The η phase morphology also changed from cellular to Widmanstatten-type during aging. The time-temperature-precipitation diagrams of these morphologies are presented. The results indicated the differences in precipitation mechanisms of η phase at 840 and 860 °C. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink