Pingli MAO
,
Yan XIN
,
Ke HAN
,
Weiguo JIANG
金属学报(英文版)
doi:10.1016/S1006-7191(08)60110-6
The volume fraction and morphology of the TCP-phase formed in two kinds of Ni-Mo-Cr-Re superalloys under different heat treatment conditions were investigated in this paper. In Re-5% alloy, with increasing of the heat treatment temperature and prolonging the holding time, the volume fraction of TCP-phase decreased and the TCP-phase size increased. At relatively lower temperature, the TCP-phase prefers to present in the dendrite cores. In Re-10% alloy, the volume fraction and size have the same change tendency as that of in Re-5% alloy, but the morphology will change from needle-like and block-like to sphere when the temperature increases. The TCP-phases formed in these two Ni-Mo-Cr-Re alloys are σ and P phase.
关键词:
Heat treatment
,
null
,
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Weiguo JIANG
金属学报(英文版)
A novel grain refiner composed of nickel, tungsten and yttria was prepared by the powder metallurgy way. The microstructure of the refiner alloy was studied by optical microscope (OM), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The refinement process was simplized. It was shown that the alloy grains could be refined by addition of the refiners apparently even at high pouring temperature. The average grain size of the refiner free alloy was 4~mm, and 0.4 mm for the refined alloy. The fine-grain superalloy has excellent mechanical properties at intermediate temperature. The refinement mechanism was discussed.
关键词:
Superalloy
