Microstructural Evolution Of Deformed GH4698 Superalloy After Solution Treatment

In 2016,the establishment of China Aviation Technology opened a new page for China's independent development of aircraft engines.The turbine disk is the heart of the aeroengine.In the turbine disk forgings,the GH4698 superalloy is widely used in aero engines because of its high temperature resistance,good structure and excellent properties.In order to support the rapid development of Chinese aviation industry,it is necessary to study the microstructure evolution behavior,espesically grain characteristes of the GH4698 superalloy turbine disk during hot processing.In this paper,the research object was GH4698 superalloy.The GH4698 was subjected to hot compression test by using Gleeble-3800 thermal simulation tester.GH4698 alloy samples with different microstructures were obtained.The microstructure evolution of GH4698 in the hot deformation process was studied.So was the effect of deformation parameters on the percentage of dynamic recrystallization of GH4698.For the GH4698 alloy with "non-mixed grain" state after hot deformation,the EBSD technology was used to study the characteristic of the grain size and its distribution,the evolution of orientation difference and the evolution behavior of the ?3 grain boundary in the continuous solution treatment process.The grain size distribution of "non-mixed grain" GH4698 after solution treatment at different times was obtained..For the GH4698 alloy with "mixed grain" state after the hot deformation,grain size and its distribution,the orientation difference,as well as ?3 grain boundary during the continuous solution treatment were studied,respectively.The mechanism of the abnormal grain growth was discussed.