Material Characterization for Metal-Cutting Force Modeling
Material Characterization for Metal-Cutting Force Modeling
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DOI：
10.1115/1.3226456
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发表时间：
1989-04
影响因子：
1.2
通讯作者：
D. Stephensen
中科院分区：
文献类型：
--
作者：
D. Stephensen
广泛应用的加工仿真程序需要可靠的切削力估计，目前只能从工艺相关的可加工性数据库中获得。开发更基本、更有效的方法的最大障碍是缺乏对切削独特变形和摩擦条件下材料屈服和摩擦行为的理解。本文介绍了一种系统的方法，指定屈服应力和摩擦特性需要作为输入的过程无关的切削力模型。采用统计学设计的端部车削试验，生成低碳钢和铝合金在各种切削条件下的切削力和切屑厚度数据。经验模型适用于切削力和模型无关的材料参数，如刀-屑摩擦系数和剪切面上的剪切应力。根据这些参数之间的相关性，检查常见的材料屈服行为假设。结果表明几何剪切应力和应变措施之间没有物理意义的相关性，几何应力和应变率措施之间的弱相关性，以及材料性能和输入变量（如切削速度和前角）之间的强相关性。上限模型被用来拟合四参数和五参数多项式应变率敏感本构方程的数据。使用该模型和经验车削力模型计算的钻削扭矩与相同材料组合的测量值相当吻合，表明端部车削试验结果可用于估计更复杂过程中的平均载荷。
Widely applicable machining simulation programs require reliable cutting force estimates, which currently can be obtained only from process-dependent machinability databases. The greatest obstacle to developing a more basic, efficient approach is a lack of understanding of material yield and frictional behavior under the unique deformation and frictional conditions of cutting. This paper describes a systematic method of specifying yield stress and friction properties needed as inputs to process-independent cutting force models. Statistically designed end turning tests are used to generate cutting force and chip thickness data for a mild steel and an aluminum alloy over a wide range of cutting conditions. Empirical models are fit for the cutting force and model-independent material parameters such as the tool-chip friction coefficient and shear stress on the shear plane. Common material yield behavior assumptions are examined in light of correlations between these parameters. Results show no physically meaningful correlation between geometric shear stress and strain measures, a weak correlation between geometric stress and strain rate measures, and a strong correlation between material properties and input variables such as cutting speed and rake angle. An upper bound model is used to fit four- and five-parameter polynomial strain-rate sensitive constitutive equations to the data. Drilling torques calculated using this model and an empirical turning force model agree reasonably well with measured values for the same material combination, indicating that end turning test results can be used to estimate mean loads in a more complicated process.