Effect of solution and two-stage aging on microstructure and hardness of Cu-containing nickel-based alloys
Microstructure and hardness of two kinds of nickel-based alloy samples containing 2.7％Cu and 0.01％Cu were studied by means of optical microscope(OM),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS)analysis,electron backscatter diffraction(EBSD)technique and microhardness tester after solution treatment and solution treatment plus two-stage aging treatment.The results show that Cu element has a significant effect on the microstructure and Vickers hardness of the nickel-based alloys.After solution treatment at 1153 ℃ for 2 h,the average grain size of the samples containing 2.7％Cu and 0.01％Cu increases to 121 μm and 178 μm,respectively,the activation energies are 3824.44 and 5603.63 kJ/mol,respectively,and the Vickers hardness decreases to 181 HV and 149 HV,respectively.After solution treatment at 1153 ℃ for 1 h and two-stage aging,the grain sizes of the samples containing 2.7％Cu and 0.01％Cu are 75 μm and 107 μm,respectively,and the Vickers hardness increases to 449 HV and 369 HV,respectively.The sample containing 2.7％Cu has fine TiN,and the Laves phase containing Cu is dispersed at grain boundaries and intergranular boundaries.The sample containing 0.01％Cu still has a large number of discontinuous Laves phases distributed in the matrix.
NETL
NSTL
万方数据
维普
