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-2015-05632
• 负责人: Attia, Mahmoud
• 金额: $ 2.11万
• 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: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=644276
• 关键词: Investigation; thermoelastic; dynamic; phenomena; improved

This proposal deals with two major issues; high performance machining processes, and predictive capability for fretting wear under complex excitation. These two issues are interrelated, since the integrity of machined surfaces control the tribological behaviour of the component. The proposal consists of the following elements (E1 to E5): ***E1. Integrated Laser Assisted Machining, Cryogenic Cooling and Minimum Quantity Lubrication: The objective is to investigate the synergetic effect of cryogenic cooling (LiN), minimum quantity lubrication on tool wear, productivity. and surface integrity in laser-assisted machining. Process optimized will defined through experimental investigation and process simulation. ***E2. Intermittent Drilling of Composites using Conventional and Superabrasive Tools: A predictive cutting force model was developed, based on a fundamental understanding of FRP composites cutting by a single diamond grain. The model will be extended to predict and optimize the orbital drilling process using superabrasive tools. Vibration-assisted drilling at high frequency-low amplitude regime will also be investigated using conventional tools. ***E3. Detection of Tool Pre-Failure in Turning Processes: The objective is to develop a system to detect unexpected tool breakage in machining. Various signals will be evaluated and special consideration will be given to feature extraction using different signal processing techniques in the time and frequency domains. A multi-sensor fusion model will be developed for 2-way communication with the NC controller. ***E4. Prediction of Machining-Induced Residual Stresses and Micro-structural Changes: A 2D FE model was developed to predict machining-induced residual stress (RS), assuming non-segmental chip formation. To improve prediction accuracy, it is proposed to consider the effects of chip segmentation, flank tool wear, and material phase transformation. For validation, oblique cutting experiments will be conducted for conventional and laser-assisted machining. ***E5. High Temperature Fretting Wear of Superalloys under Pseudo Random Excitation: Following the experiments on the role of surface oxide in fretting wear of cobalt-based superalloys at 550oC, a FE-based model was developed to estimate friction-induced temperature rise, considering the spatial and height random distributions of contact asperities. The applicant's `generalized fretting wear theory', will be extended by considering the effect of: (a) crack initiation and propagation due to frictional heating, (b) oxidation kinetics, and (c) random excitation; an aspect that has not been investigated before. **

该提案涉及两个主要问题；高性能加工工艺以及复杂激励下微动磨损的预测能力。这两个问题是相互关联的，因为加工表面的完整性控制着部件的摩擦学行为。该提案由以下要素组成（E1 至 E5）： ***E1。集成激光辅助加工、低温冷却和微量润滑：目的是研究低温冷却 (LiN)、微量润滑对刀具磨损和生产率的协同效应。和激光辅助加工中的表面完整性。优化的工艺将通过实验研究和工艺模拟来定义。 ***E2。使用传统和超级磨料工具对复合材料进行间歇钻孔：基于对单个金刚石颗粒切割 FRP 复合材料的基本了解，开发了预测切削力模型。该模型将扩展到预测和优化使用超级磨料工具的轨道钻探过程。还将使用传统工具研究高频低振幅状态下的振动辅助钻井。 ***E3。车削过程中刀具预故障的检测：目标是开发一种系统来检测加工中的意外刀具破损。将评估各种信号，并特别考虑在时域和频域中使用不同信号处理技术进行特征提取。将开发多传感器融合模型，用于与 NC 控制器的双向通信。 ***E4。预测加工引起的残余应力和微观结构变化：假设非分段切屑形成，开发了一个二维有限元模型来预测加工引起的残余应力 (RS)。为了提高预测精度，建议考虑切屑分割、后刀面磨损和材料相变的影响。为了验证，将对传统加工和激光辅助加工进行倾斜切割实验。 ***E5。伪随机激励下高温合金的高温微动磨损：继表面氧化物在 550oC 钴基高温合金微动磨损中的作用的实验之后，开发了一种基于有限元的模型来估计摩擦引起的温升，并考虑接触粗糙体的空间和高度随机分布。申请人的“广义微动磨损理论”将通过考虑以下效应来扩展：(a)由于摩擦加热而引起的裂纹萌生和扩展，(b)氧化动力学，以及(c)随机激励；以前没有研究过的一个方面。 **