| GH4169 alloy has good oxidation resistance,radiation resistance,and corrosion resistance below 650℃.It also has good hot workability and excellent welding performance.As a major engine component such as blades,it is universal Using materials,the alloy has been widely used in aerospace and other related fields.However,there are still some key technical problems in the processing of the alloy,such as the alloy’s high resistance to deformation conditions,the high temperature during the deformation process,and the stricter temperature range requirements during the deformation process.Hot processing greatly improves the performance of the nickel-based alloy itself,but it often occurs that the crystal grains are coarse and mixed due to unreasonable process design,which has extremely adverse effects on the material properties.Therefore,in order to solve this critical core technical problem,we need to carry out effective control at the thermal process level of the alloy and further develop newer and more effective processes.Through a comprehensive and systematic study of the deformation behavior of the alloy material under high temperature conditions,the performance of the engine can be further improved.This paper takes the cast and forged GH4169 alloy as the main research objective,combined with the related microstructure analysis,and uses the hot compression test to study the hot deformation behavior of the as-cast and forged GH4169 alloy and the evolution of the microstructure of the alloy.Draw the true stress-strain curve of the alloy in the two states of casting and forging,and analyze the influence of different thermal deformation parameters（including deformation rate and deformation temperature）on the deformation of the alloy in the as-cast and forged states,according to Johnson-Cook（JC）,The modified Johnson-Cook（MJC）and strain-compensated Arrhenius three models established the constitutive equation of the alloy,and through the use of DMM（Dynamic Material Model）,the hot working diagrams of the alloy as-cast and forged were drawn.Analyze the characteristics of the microstructure after deformation to obtain the most ideal forging and rolling process parameters of GH4169.The research results are as follows:GH4169 alloy is a kind of high temperature alloy with strain rate and temperature sensitive characteristics.The deformation temperature and strain rate are the two main factors affecting the flow stress of the alloy.For as-cast GH4169 alloy,the higher the deformation temperature is,the more obvious the dynamic recrystallization is.Under the condition of constant deformation temperature,the greater the value of strain rate,the recrystallization degree first decreases and then increases with the increase of deformation rate value;for forged GH4169 alloy,the deformation rate is not When the temperature changes,the temperature increases,the degree of recrystallization and the grain size increase;when the deformation temperature is constant,as the strain rate decreases,the dynamic recrystallization rate gradually increases.Comparing and analyzing three different types of constitutive equations,it is obvious that the Arrhenius model has higher prediction accuracy than other models,and can better predict the flow stress of as-cast GH4169,and its correlation coefficient（R）is The numerical value and the average relative error（AARE）were 0.961 and 9.31%,respectively.At the same time,the constitutive equation of forged GH4169 was obtained through the strain-compensated Arrhenius model,and its correlation coefficient（R）and average relative error（AARE）were 0.99033 and 4.82%,respectively.According to DMM（also known as dynamic material model）,the hot working drawing of GH4169 alloy in two states of casting and forging is obtained.The deformation temperature of 1060-1100℃and the strain rate of0.04-0.18s-1 are the most ideal deformation process parameter ranges for the as-cast GH4169 alloy.Deformation temperature of 1040-1070℃and strain rate of 0.01-0.13s-1are the most ideal deformation process parameter ranges for forged GH4169 alloy. |
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