Pervaiz Salman, Samad Wael A
Department of Mechanical and Industrial Engineering, Rochester Institute of Technology-Dubai Campus, Dubai P.O. Box 341055, United Arab Emirates.
Materials (Basel). 2021 Aug 25;14(17):4820. doi: 10.3390/ma14174820.
In drilling operations, cutting forces are one of the major machinability indicators that contribute significantly towards the deviations in workpiece form and surface tolerances. The ability to predict and model forces in such operations is also essential as the cutting forces play a key role in the induced vibrations and wear on the cutting tool. More specifically, Inconel 718-a nickel-based super alloy that is primarily used in the construction of jet engine turbines, nuclear reactors, submarines and steam power plants-is the workpiece material used in the work presented here. In this study, both mechanistic and finite element models were developed. The finite element model uses the power law that has the ability to incorporate strain hardening, strain rate sensitivity as well as thermal softening phenomena in the workpiece materials. The model was validated by comparing it against an analytical mechanistic model that considers the three drilling stages associated with the drilling operation on a workpiece containing a pilot hole. Both analytical and FE models were compared and the results were found to be in good agreement at different cutting speeds and feed rates. Comparing the average forces of stage II and stage III of the two approaches revealed a discrepancy of 11% and 7% at most. This study can be utilized in various virtual drilling scenarios to investigate the influence of different process and geometric parameters.
在钻孔操作中，切削力是主要的可加工性指标之一，对工件形状偏差和表面公差有显著影响。预测和模拟此类操作中的力的能力也至关重要，因为切削力在切削刀具的振动和磨损中起着关键作用。更具体地说，因科镍合金718（一种主要用于喷气发动机涡轮机、核反应堆、潜艇和蒸汽发电厂建设的镍基超级合金）是本文所介绍工作中使用的工件材料。在本研究中，开发了机械模型和有限元模型。有限元模型采用幂律，能够考虑工件材料中的应变硬化、应变速率敏感性以及热软化现象。通过将该模型与一个分析机械模型进行比较来验证，该分析机械模型考虑了在有导向孔的工件上进行钻孔操作的三个钻孔阶段。对分析模型和有限元模型进行了比较，发现在不同切削速度和进给率下结果吻合良好。比较两种方法在第二阶段和第三阶段的平均力，发现最大差异分别为11%和7%。本研究可用于各种虚拟钻孔场景，以研究不同工艺和几何参数的影响。
