| Title |
Research Paper - Mechanical Behavior - : Mechanical Properties and Active Mechanism of Strengthening of Rapid Solidification Processed Superalloy A - 286 |
| Authors |
신기삼(Kee Sam Shin); 이성학(Sung Hak Lee); (Thomas F . Kelly); (John E . Flinn) |
| Abstract |
Mechanical test data of superalloy A-286 show that there is a significant increase in tensile strength after rapid solidification processing (RSP). The mechanism of mechanical property improvement upon RSP was studied by TEM quantitative defect analysis and the data analysis using strengthening models. The most prominent microstructural alterations by RSP are found in the precipitates and in the grain growth behavior. On average, the precipitates in RSP samples are smaller, have higher volume fractions, and are much more stable than their conventionally processed counterparts. The increased tensile strength of the RSP samples is found to be the result of the increased volume fraction and number density of second phase particles. However, the strengthening came mostly through grain growth inhibition by the second phase particles, which in turn increased the strength via Hall-Petch relationship. This study shows the importance of recrystallization and thus the method of consolidation for effective strengthening. |