预应力条件对镍基高温合金切削加工的影响

INFLUENCE OF PRESTRESS CONDITION ON MACHINING OF NICKEL- BASED SUPERALLOYS

为研究预应力条件对镍基高温合金切削加工的影响,采用Abaqus/Explicit软件建立了预应力切削镍基高温合金的三维有限元模型,研究了不同预应力状态下的切削力和加工表面各向应力的分布规律,分析了预应力条件对切屑形状、切削力和表面残余应力的影响,并与实验结果进行对比。研究结果表明:预应力作用对切削力和切屑形状的影响不显著;预应力作用对与预应力加载方向相同的已加工表面应力影响最大,并随着预应力的增大此方向上应力的分布层深显著增大,而对其他方向上的应力分布影响不显著;在一定范围内,随着预应力的增大已加工表面残余压应力值大小和分布层深都显著增大。

In order to reveal the effect of prestress conditions on prestressed cutting nickel-based alloy, a finite element prestressed cutting model was established in Abaqus/Explicit software. The cutting force curves and surface stresses in different directions under conditions of different prestress were simulated, the influence of the prestress to chip shape, cutting force and surface residual stress were analyzed and experimentally validated. The results indicate that the influence of prestress on cutting force and chip shape was unremarkable. The subsurface stress which shares the same loading direction of prestress was greatly affected by the prestress, furthermore, with the increase of prestress the magnitude and gradient of this subsurface stress increase significantly, while there＇ s no notable influence on the subsurface stress of other directions. Finally, within a certain extent of prestress, the larger magnitude of applied prestress, the larger magnitude and distribution depth of residua compressive stress is generated.