Effect of the Type of Melt-Atomized Powder on the Behaviour of the Ni-Based Superalloy HIPped Compact under High Temperature Compression Tests

摘要

Results of compression tests of the specimens of the type EP741NP Ni-based superalloy in the temperatures range of 1050 to 1200°C and investigation of the microstructure features are presented. The specimens were cut from PM HIP compacts fabricated using the rapidly quenched powders produced by the gas atomization technique (GA) and plasma rotating electrode process (PREP). An analysis of the stress-strain curves and the features of the microstructure and distribution of boron were performed. The following main methods were used for the specimen investigation: light metallography and autoradiography on boron. Effect of the type of the melt-atomized powder on the flow stress of the HIPped compact and the features of the microstructures such as necklace, ultra high dispersion types were detected. Correlations of these peculiarities of the microstructure with boron distribution and the features of the stress-strain curves were established.