Analysis of the heat input into the workpiece due to drilling and the resulting influences on the wall of the hole for 42CrMo4

分析 42CrMo4 钻孔时工件的热输入及其对孔壁的影响

• 批准号: 179125425
• 负责人: Professor Dr.-Ing. Volker Schulze
• 金额: --
• 依托单位: Institut für Produktionstechnik (WBK)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/179125425?language=en
• 关键词: Analysis; heat; input; into; workpiece

The third phase of the project focusses on an active geometric compensation of thermal deformations for a complex component with drilling holes for AISI 4140 (German Grade 42CrMo4). This goal will be achieved by a simulation-based design of machining strategies. An increase of complexity compared to the second phase of the project will be achieved by intersecting drilling holes in combination with further drillings on the component. With this example, the interactions of thermally and thereby mechanically induced effects can be represented much better during the drilling operation.To reach this objective, the simplified 3D-Model of a drilling operation achieved during the last period will be adjusted to the changed starting position and validated experimentally at the beginning. For this transfer step the modular model construction can be used to tailor each partial model to its specific application. As part of this work, the temperature terms implemented in the model for the heat input of the drill will be extended simultaneously for a universal design of the drill geometry. With the help of the advanced simulation model the overall heat balance which is responsible for the formation of residual stress and distortion states will be investigated by parametric studies. In this way essential information for the targeted generation of resiudal stresses and the resulting distortions can be obtained. A parametrization of the workpiece with respect to the distance of drilling holes will complete this workpackage. After the heat balance can be fully described, the investigation of the use of cold sources will follow aiming to minimize the distortion potential by controlled cooling of a simplified component. This cold sources are to be used to run after the manufacturing process, but also parallel to the production of further drilling holes. As a result of the calculations in the model the best times, places and intensities for the activation of the cold sources will be obtained. In a subsequent development step a circular milling model will be developed as a further method for compensating the residual stress and distortion conditions and tested again in the simplified component. With this model, drilling geometries will be examined in terms of roundness and orientation in order to derive compensation strategies for the distortion behavior resulting from controlled non-circular and curved drilling of the holes. This allows to produce holes and overall geometries, which are ideal after reaching the thermal equilibrium. In the final step, the active geometric compensation will be carried out under synergetic use of all gained insights and results and application of circular milling and cold sources for the complex component. At the end the effects of single or multiple compensation strageties will be vaildated experimentally.

该项目的第三阶段重点是对复杂部件的热变形进行主动几何补偿，该部件具有AISI 4140（德国等级42CrMo4）的钻孔。这一目标将通过基于仿真的加工策略设计来实现。与项目第二阶段相比，复杂性的增加将通过交叉钻孔和部件上的进一步钻孔来实现。通过这个例子，可以更好地描述钻井作业过程中热效应和机械效应的相互作用。为了达到这个目标，在最后一个阶段获得的简化的钻井作业3D模型将被调整到改变的起始位置，并在开始时进行实验验证。对于该转移步骤，模块化模型构造可用于使每个部分模型适合其特定应用。作为这项工作的一部分，在模型中实现的钻头的热输入的温度项将被扩展，同时钻几何形状的通用设计。借助先进的模拟模型，将通过参数研究来研究导致残余应力和变形状态形成的整体热平衡。通过这种方式，可以获得用于有针对性地产生残余应力和由此产生的变形的基本信息。根据钻孔距离对工件进行参数化将完成此工作包。在热平衡可以被充分描述之后，冷源的使用的调查将遵循旨在通过简化部件的受控冷却来最小化变形潜力。这种冷源是用来运行后的制造过程中，但也平行于生产进一步钻孔。作为模型计算的结果，将获得激活冷源的最佳时间、地点和强度。在随后的开发步骤中，将开发圆形铣削模型作为补偿残余应力和变形条件的进一步方法，并在简化部件中再次进行测试。利用该模型，将在圆度和方向方面检查钻孔几何形状，以便导出用于由受控非圆形和弯曲钻孔引起的变形行为的补偿策略。这允许产生孔和整体几何形状，这在达到热平衡后是理想的。在最后一步中，将在协同使用所有获得的见解和结果以及针对复杂部件的圆铣削和冷源的应用的情况下进行主动几何补偿。最后通过实验验证了单一或多种补偿策略的效果。