关键词: 服役, γ'相粗化, 碳化物分解, 固溶处理, 溶解激活能

Abstract:

The turbine blades are usually utilized in hot sections of aero-engines and industrial gas turbines; therefore, study of the damaged behavior of turbine blade for the manufacture and repair of turbine blade is extremely meaningful. The creep damage behavior for long-term and short-term serviced turbine blades was investigated. There is a similar mechanism for the occurrence of creep-induced cavities between the long-term and short-term serviced blades. However, the difference of the degeneration of γ' precipitates and carbides for the two kinds of blades was found. γ' precipitates for the long-term serviced blade had a more irregular and coarser morphology than the short-term serviced blade. There existed a decomposition of carbides from MC type to M₂₃C₆ type for the long-term serviced blade, whereas, for the short-term serviced blade the decomposition of carbides was from MC₍₁₎ type to MC₍₂₎ type. Likewise, effects of different solutioning schedules on two kinds of blade materials (K002 and GTD-111 superalloys) were studied. As a result, increasing the solution temperature and holding time can promote the occurrence of γ' dissolution. The dissolution activation energies for two kinds of alloys were increased with the increase of holding time. The values of dissolution activation energy for K002 alloy with different holding times were greater than those for GTD -111 alloy.

Key words: service, γ' coarsening, carbide decomposition, solutioning, dissolution activation energy