Aero-engine hollow turbine blades are work under prolonged high temperature,requiring high dimensional accuracy.Blade profile and wall thickness are important parameters to ensure the comprehensive performance of blad...Aero-engine hollow turbine blades are work under prolonged high temperature,requiring high dimensional accuracy.Blade profile and wall thickness are important parameters to ensure the comprehensive performance of blades,which need to be measured accurately during manufacturing process.In this study,a high accuracy industrial computed tomography(ICT)measuring method was developed based on standard cylindrical pin and ring workpieces of different sizes.Combining ICT with cubic spline interpolation,a sub-pixel accuracy was achieved in measuring the dimension of component.Compared with the traditional and whole-pixel level image measurement method,the cubic spline interpolation algorithm has the advantages of high accuracy in image edge detection and thus high accuracy of dimensional measurement.Further,the technique was employed to measure the profile and wall thickness of a typical aerospace engine turbine blade,and an accuracy higher than 0.015 mm was obtained.展开更多
The recrystallization behaviors of a nickel-based single crystal superalloy during heat treatment at 1,200℃ for 4 h with various cooling rates were studied.Results show that the thickness of recrystallization layer d...The recrystallization behaviors of a nickel-based single crystal superalloy during heat treatment at 1,200℃ for 4 h with various cooling rates were studied.Results show that the thickness of recrystallization layer decreases with the increase of cooling rate.In addition,the microstructures ofγ′phase in the recrystallization region are different in various cooling rates.In the high cooling rates(70,100℃·min^(-1)),small size and high volume fraction ofγ′phases are formed in the recrystallization region.It is also found that irregular fine secondaryγ′phases are precipitated between matrix channels with an average size of 150 nm in the original matric(100℃·min^(-1)).The sizes of the secondaryγ′phase decrease with the increase of cooling rate.In contrast,large size and small volume fraction ofγ′phases are formed in the recrystallization region,and a grain boundary layer is formed under a low cooling rate(10℃·min^(-1)).The evolution mechanism of recrystallization at various cooling rates during heat treatment is analyzed.展开更多
基金financially supported by the National Science and Technology Major Project "Aero Engine and Gas Turbine"(No.2017-Ⅶ-0008-0102)National Nature Science Foundation of China (No.51701112 and No.51690162)+1 种基金Shanghai Rising-Star Program (No.20QA1403800 and No.21QC1401500)Shanghai Science and Technology Committee (No.21511103600)
文摘Aero-engine hollow turbine blades are work under prolonged high temperature,requiring high dimensional accuracy.Blade profile and wall thickness are important parameters to ensure the comprehensive performance of blades,which need to be measured accurately during manufacturing process.In this study,a high accuracy industrial computed tomography(ICT)measuring method was developed based on standard cylindrical pin and ring workpieces of different sizes.Combining ICT with cubic spline interpolation,a sub-pixel accuracy was achieved in measuring the dimension of component.Compared with the traditional and whole-pixel level image measurement method,the cubic spline interpolation algorithm has the advantages of high accuracy in image edge detection and thus high accuracy of dimensional measurement.Further,the technique was employed to measure the profile and wall thickness of a typical aerospace engine turbine blade,and an accuracy higher than 0.015 mm was obtained.
基金financially supported by the National Natural Science Foundation of China(No.92060104)the National Science and Technology Major Project(No.2017-VII-00080102)the Shanghai Municipal Science and Technology Committee Grant(No.20511107700)。
文摘The recrystallization behaviors of a nickel-based single crystal superalloy during heat treatment at 1,200℃ for 4 h with various cooling rates were studied.Results show that the thickness of recrystallization layer decreases with the increase of cooling rate.In addition,the microstructures ofγ′phase in the recrystallization region are different in various cooling rates.In the high cooling rates(70,100℃·min^(-1)),small size and high volume fraction ofγ′phases are formed in the recrystallization region.It is also found that irregular fine secondaryγ′phases are precipitated between matrix channels with an average size of 150 nm in the original matric(100℃·min^(-1)).The sizes of the secondaryγ′phase decrease with the increase of cooling rate.In contrast,large size and small volume fraction ofγ′phases are formed in the recrystallization region,and a grain boundary layer is formed under a low cooling rate(10℃·min^(-1)).The evolution mechanism of recrystallization at various cooling rates during heat treatment is analyzed.
