烧结态W-80Cu合金高温压缩变形行为及本构关系

High Temperature Compression Deformation Behavior and Constitutive Relationship of Sintered W-80Cu Alloy

采用Gleeble-1500D热模拟试验机研究了烧结态W-80Cu合金的热变形行为,分析了热变形参数对合金流变应力的影响。研究结果表明:稳态流变应力与应变率呈正相关,与变形温度呈负相关。经热压缩试验后,材料孔隙度减少,两相界面结合紧密,相对致密度得以提高。利用Zene-Hollomon参数的双曲正弦模型,建立了烧结态W-80Cu合金热变形本构方程ε=2.353×10^6[sinh(0.022 96σ)]^4.009 0×exp[-89.596×10^3/(RT)]。该方程预测值与试验观测值重合度好,能较好地描述烧结态W-80Cu合金高温热压缩下的致密化行为。

The thermodynamic behavior of sintered W-80 Cu alloy was investigated in isotermal compression experiment on the Gleeble-1500D thermal simulation testing machine.The effect of thermal deformation parameters on the flow stress of the alloy was analyzed.The results show that the the steady-state rheological stress of W-80Cu alloy increases with the increasing of strain rate,and decreases with the increaseing of deformation temperature.The interface of the tungsten and copper is combined tightly through the thermal compression experiment.The relative density of W-80 Cu alloy is improved because of the reduction of porosity.Moreover,a hypebolic sinusoidal model containing zene-hollomon parameters is used to establish the constitutive equation of the sintered W-80Cu alloy during high temperature compression densification process,which isε·=2.353×10^6[sinh(0.022 96σ)]^4.009 0 exp[-89.596×10^3/(RT)].The calculated value is in good agreement with the experimental value,which can describe the thermal deformation behavior of the sintered W-80Cu alloy during high temperature compression densification process.