CrMnFeCoNiZr High Entropy Alloy Hot Working Behavior And Finite Element Mothod Simulation

The preparation of multi-component high-entropy alloys is beyond the design concept of one or two principal elements of traditional alloys.These alloys usually include five or more principal elements,each containing no more than 35%and not less than 5%.The design concept of high-entropy alloy start a new field for material research,through a reasonable alloy composition,high entropy alloy can have the advantages of high hardness,high strength,corrosion resistance,high temperature creep,electromagnetic resistance,high temperature oxidation and other excellent performance at the same time.In this paper,CrMnFeCoNi high entropy alloy study found that the HV hardness is only 157.62,under the compression conditions of high temperature?950?1100 ??and strain rate(0.001?0.1s^-1),the maximum compressive strength is not more than 300MPa.In order to improve its high temperature performance,the Zr element with relatively larger atomic radius and relatively more negative electronegativity was added to the CrMnFeCoNi high entropy alloy to form a simple intermetallic compound phase,which was distributed evenly over the CrMnFeCoNi high entropy alloy matrix.The results show that the CrMnFeCoNiZrx?x=0,0.5,1.0,2.0?high entropy alloy has a maximum HV hardness value of 794.23,increased 403.89%;the maximum strength of 690MPa with high temperature?950?1100 ??and strain rate(0.001-0.1^s-1),increased by 130%.The microstructure of CrMnFeCoNiZr,?x = 0,0.5,1.0,2.0?with different Zr content is studied.The results show that when x = 0.the phase structure is the singles olid solution phase of the FCC crystal structure,when x = 0.5,The phase structure is FCC solid solution phase and ZrCo2.9 intermetallic compound phase;x = 1.0 and 2.0,the phase structure are FCC solid solution phase and intermetallic compound phase of P63.According to the theory of dynamic material model?DMM?,the thermal processing of CrMnFeCoNiZrx?x = 0,0.5?high entropy alloy from true strain 0.3 to 0.6 is established.In the current experimental conditions(950?1100?,0.001?0.1^-1),there is no thermal processing instability zone for CrMnFeCoNi high entropy alloy,but the most suitable thermal processing area is relatively small,only the strain rate of 10-1.3?10-1.0 corresponding to the 1050?1070?In the current experimental conditions,the most suitable thermal processing temperature is 1020?1090?,the corresponding strain rate is 10-3?10-2.3 for CrMnFeCoNiZr0.5 high entropy alloy.Based on the Arrhenius hyperbolic sine model,the constitutive model of CrMnFeCoNiZrx?x=0,0.5?high entropy alloy was established according to the Gleeble axisymmetric isothermal compression curve at different strain rates and temperatures.The correlation coefficients R are 0.99908 and 0.99927 respectively,the average absolute relative error AARE is 2.9945%and 2.8817%respectively.In this paper,according to constitutive equation of CrMnFeCoNiZr0.5 high entropy alloy and the hot working map,thermoforming process of turbine disk are simulated based on FEM,and 0.002^s-1 is excellent stain rate,the corresponding temperature is 1080?.