INVESTIGATION OF THERMOELASTIC AND DYNAMIC PHENOMENA FOR IMPROVED DESIGN AND CONTROL OF MANUFACTURING AND TRIBOLOGICAL SYSTEMS

研究热弹性和动态现象以改进制造和摩擦系统的设计和控制

• 批准号: RGPIN-2020-06223
• 负责人: Attia, Mahmoud
• 金额: $ 3.35万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=718266
• 关键词: INVESTIGATION; THERMOELASTIC; DYNAMIC; PHENOMENA; IMPROVED

This proposal deals with high performance machining processes and the prediction of fretting wear under complex excitation. These issues are interrelated, since the integrity of machined surfaces controls its tribological behaviour. Four projects P1 to P4 are proposed: P1-Development of a real-time tool wear prediction, and pre-failure detection system In Phase-1, a novel approach was developed to detect and stop the turning operation before tool chipping (within 20 milliseconds). The objective of the proposed work is to extend this approach to monitoring tool wear level and to detect tool pre-failure in high speed milling of Ti alloys and difficult-to-cut materials, where thermal effects have significant effect. The system should also be operating in the presence of an adaptive control system. Outcome and impact: It is anticipated the proposed system will be unique and can reduce the cost by 20%. P2-Process development for cryogenic deep-hole drilling Building on the success in Phase-1 for turning, the objective is to develop a cryogenic deep hole drilling process, using liquid nitrogen (LiN), overcoming the challenge of injecting LiN in a confined space through a rotating tool. Combining LiN with a minimum quantity lubrication (MQL) jet will be investigated, through CFD modeling to understand the flow characteristics of the dual LiN and MQL jets when supplied through the tool. Comparison between the performance of LiN and supercritical CO2 cryogens will be carried out. Outcome and impact: Compared to flood cooling of Ti6Al4V, it is anticipated that the tool life improvement will be ~ 100% and the environmental impact will be two orders of magnitude. P3-Development of a mixed-regime vibration-assisted drilling (VAD) process for hybrid stacked composites-metal structure The objective is to develop a novel mixed-regime VAD process that superimposes low frequency-high amplitude (LFHA ) and high frequency-low amplitude (HFLA) excitations to explore the possibility of gaining the benefits of both regimes and to allow adaptive control of the process through adjustment of the frequency/amplitude levels and/or the feedrate when drilling FRP/metal stacks. Outcome and impact: From simulation results, it is anticipated that the reduction in forces and temperature will exceed the individual benefits of each regime. As enabling technology, this development will overcome the challenges of robotized machining of stacked structures. P4-Modeling and experimental investigation of fretting wear under random vibration The main objective is to extend the generalized fretting wear theory' proposed by the applicant to predict the damage under random excitation, and to develop a new experimental methodology for the standardization of fretting wear tests under random excitations. Outcome and impact: Preliminary test results showed that conventional sinusoidal excitation testing is non-conservative and could have significant safety and economic implications.

该提案涉及高性能加工过程和在复杂激发下对壁磨损的预测。这些问题是相互关联的，因为加工表面的完整性控制了其摩擦学行为。提出了四个项目P1至P4： 实时工具磨损预测和实用检测系统的P1开发 在第1阶段，开发了一种新的方法来检测和停止在工具芯片之前（20毫秒内）。拟议工作的目的是将这种方法扩展到监测工具磨损水平，并在高速铣削的Ti合金和难以切割的材料中检测工具预击，在热效应具有显着效果的情况下。该系统还应在自适应控制系统的情况下运行。结果和影响：预计拟议的系统将是独一无二的，可以将成本降低20％。 低温深孔钻孔的P2过程开发 基于阶段1的成功，目标是使用液氮（LIN）开发一个低温深孔钻孔过程，从而克服了通过旋转工具将LIN注射到密闭空间中的挑战。通过CFD建模将研究LIN与最低量润滑（MQL）射流的结合，以了解通过工具提供时双Lin和MQL Jets的流动特性。将进行LIN和超临界二氧化碳冰冻的性能之间的比较。结果和影响：与TI6AL4V的洪水冷却相比，预计工具寿命的改善将为100％，环境影响将为两个数量级。 混合振动钻探（VAD）的P3开发用于混合堆叠的复合材料 - 金属结构 目的是开发一种新型的混合活体VAD工艺，该过程将低频高振幅（LFHA）和高频振幅（HFLA）激发叠加叠加，以探索探索这两种状态的益处的可能性，并通过调整频率/振幅/或饲料量进行钻孔时，可以自适应地控制该过程，并允许对过程进行自适应控制。结果和影响：从仿真结果中，预计力和温度的降低将超过每个制度的个人益处。作为启用技术，这种发展将克服堆叠结构的机器人加工的挑战。 在随机振动下的P4模型和实验研究 主要目的是扩展申请人提出的广义刷磨损理论，以预测随机激发下的损害，并开发一种新的实验方法，用于在随机激发下对壁穿磨损试验进行标准化。结果和影响：初步测试结果表明，常规的正弦激发测试是非保守的，并且可能具有重大的安全性和经济影响。