A Pt-modified Ni-base superalloy with high temperature precipitate stability

作者：Van Sluytman Jason S^*; Moceri Charles J; Pollock Tresa M

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2015, 639: 747-754.

DOI：10.1016/j.msea.2015.05.023

• Nickel base superalloys
• Interdiffusion
• Moment invariant
• Precipitate coarsening
• Platinum group metal

Nickel-base alloys display exceptional mechanical properties to high fractions of their melting point due to the presence of L1(2) gamma' precipitates. However, above 1000 degrees C, the precipitates typically coarsen or rapidly undergo shape changes along with dissolution into the matrix, thereby degrading the mechanical performance of the alloy at higher temperatures. In this research, a Pt-modified Ni-base alloy with exceptional high temperature stability has been identified. Coarsening studies conducted in the temperature range from 1050-1200 degrees C reveal unusually high volume fractions of morphologically stable gamma' precipitates up to 1200 degrees C. Electron-probe micro-analysis demonstrates strong partitioning of Pt to the gamma' phase. The presence of a high volume fraction of slowly coarsening precipitates at 1200 degrees C suggests that the alloy would have excellent performance as a bond coat and/or single crystal blade.

• 出版日期2015-7-15