Aeroengine Turbine Disk GH4133B Alloy Fatigue Crack Propagation Numerical Simulation Study

As the main material for turbine disc of aero engines,GH4133 B nickel-based super alloy has a superior durability and fatigue properties.This article studies the experiments about the fatigue crack growth rate of GH4133 B nickel-based super alloy at the normal temperature level,using ABAQUS finite element software to calculate the crack tip stress intensity factor of standard CT specimen and using the extended finite technique to simulate the cracking process of fatigue cracks.Carrying out experiment about long fatigue crack propagation of GH4133 B alloy.The experiment subjects are GH4133 B alloy standard CT specimens with different stress ratios of the fatigue crack propagation.OLYMPUS BX51 M microscope is adopted to track the crack,and some fatigue crack propagation lengths under cycles are obtained.Fatigue crack growth rate is obtained by using derivative approximation methods,based on the relations between fatigue crack growth in the length and number of cycles.The relative energy release rate under various crack length is obtained by using theoretical formula.The corresponding fatigue crack growth rate function is obtained by combining relative energy release rate under various crack length and Paris‘law fitting fatigue crack growth rate curve.The residual fatigue life of the standard CT specimen is estimated by using Paris formula derived formula.The residual fatigue life of No.1 to 16 samples is calculated with Simpson integration,by combining fitting parameters C and m.The result shows that there is slight error between theoretic residue life and tested residue life.By comparing with the experimental results,estimated residual life formula is corrected.The result shows that corrected formula can predict the residual life more accurately.Using finite element analysis software ABAQUS,finite element calculation function is expanded and CT specimen finite element model is established to calculate stress intensity factor under different crack length.Using experimentally obtained fatigue crack extension of Paris formula parameters,the fatigue damage criterion is established in ABAQUS to simulate the fatigue crack propagation behavior under different stress ratios.By comparing fatigue crack propagation life experiment,theory and simulation of life,it shows that life error is within an acceptable range,indicating the effectiveness of the fatigue crack propagation numerical simulation.In this paper,the experiments about the fatigue crack growth rate of GH4133 B nickel-based super alloy is carried out and the results is compared with finite analysis results.The analysis of CT specimen fatigue behavior with the extended finite element method can be used to preview the material fatigue test,and guide the fatigue test.On this basis,it is possible to simulate the fatigue behavior of the various components,and thus provides new ideas for the engineering design analysis.