Abstract
A comparative investigation of σ-phase transformation in base and modified experimental alloy RR2072 (C, Hf, and B) has been undertaken. The alloys were exposed at 950 °C for 5 to 500 hours. It was found that σ-phase transformation was notably retarded in the modified alloys due to the prior formation of M23C6 carbides and Ta/Ti being tied up in the MC phase. Detailed investigation has revealed that M23C6 carbides absorb Cr, Mo, and Co, consequently retarding σ-phase transformation that demands Cr, Mo, and Co in addition to Re. In the interdendritic regions, the growth of σ-phase was physically limited by MC carbides and chemically inhibited by the very localized microsegregation.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
