High performance machining of lightweight composites and advanced aerospace alloys

现代飞机应该确保减少燃油消耗以及减少二氧化碳、氮氧化物和噪音排放。为此，机身和发动机制造的改进是必要的。这意味着机身和发动机使用轻质材料，圆盘和叶片使用先进的涡轮材料。最广泛使用的先进高强度合金是铝和耐火合金，以及轻质复合材料，如纤维增强塑料(FRP)、碳纤维或玻璃纤维增强聚合物(C/GFRP)和钛金属基复合材料(TiMMC)，以及用于飞机发动机、镍和钛合金。这些材料在汽车和生物医学领域也具有巨大的潜力。*在咨询了业界(普惠、RTI、美国铝业和庞巴迪)后，利用这项发现基金，我们将重点评估两种材料：钛金属基复合材料(TiMMCs)和碳纤维增强聚合物(CFRP)。我们的初步研究和文献回顾使我们有机会定义一个工作假设：*1.通过适当控制初始切削条件和初始刀具磨损，有可能将整个刀具寿命提高至少20%。*2.使用更适合复合材料CFRP的新的表面粗糙度分析方法和参数，即使用分形分析，可以更准确地预测零件的使用性能。*3.基于模式识别和逻辑分析的数据，通过生存分析、分形分析和刀具磨损监测，可以改进刀具寿命估计。*初始切削条件，初始刀具磨损，而它们在加工TiMMC时对整个刀具寿命的影响以前从未被研究过。我们的初步工作还表明，混沌理论和分形学在分析初始切削条件和表面粗糙度方面具有很好的应用前景。分形理论已经在许多工程和技术应用中被证明是非常有效的，并可以极大地改变机械加工的研究方法。因此，这项工作的原创性在于使用混沌理论和分形学作为一种方法来理解刀具磨损和生成新的、有意义的含纤维塑料(CFRP)表面粗糙度参数。这种新的方法还可以极大地提高刀具的诊断和监测以及切削参数的优化。我们并不声称要革新机械加工理论，但我们打算为机械加工过程的分析带来一个新的视角。*目标：*本研究计划的主要目标是对新型先进航空合金、碳纤维或玻璃纤维增强聚合物(C/GFRP)的可加工性、刀具磨损建模和分析提供新的见解，并开发更适合于复合材料的新的表面分析方法和粗糙度参数。**

Modern aircraft should ensure reduced fuel consumption as well as reduced CO2, NOx, and noise emission. To this end, airframe and engine manufacturing improvements are necessary. This implies the use of lightweight materials for airframes and engines and advanced turbine materials for discs and blades. The most widely used advanced high strength alloys for airframes are aluminium and refractory alloys and lightweight composite materials like Fiber Reinforced Plastic (FRP), Carbon or Glass Fiber Reinforced Polymer (C/GFRP), and Titanium Metal Matrix Composites (TiMMCs), and for aircraft engines, nickel and titanium alloys. These materials also have great potential for the automotive and biomedical sectors.***After consulting with industry (Pratt&Whitney, RTI, Alcoa, and Bombardier), with this discovery grant, we will focus on evaluation of two materials: Titanium Metal Matrix Composites (TiMMCs) and Carbon Fiber Reinforced Polymer (CFRP). Our preliminary research and a literature review give us the opportunity to define a working hypothesis:***1. It is possible to increase the entire tool life by at least 20% by appropriate control of initial cutting conditions and initial tool wear.***2. Part performance in service can be predicted more accurately using new surface roughness analysis methods and parameters better adapted to composite materials CFRPs, namely using fractal analysis.***3. Tool life estimations can be improved using survival analysis, fractal analysis, and tool wear monitoring based on pattern recognition and Logical Analysis of Data.***Initial cutting conditions, initial cutting tool wear, and their impact on entire tool life when machining TiMMCs have never been studied before. Our preliminary works also show that the application of chaos theory and fractals for analysis of initial cutting conditions and surface roughness is very promising. The theory of fractals has already proven highly effective in many engineering and technology applications and can dramatically change research methods in machining. Consequently, the originality of this work lies in the use of chaos theory and fractals as an approach to understand cutting tool wear and to generate new, meaningful surface roughness parameters for plastics containing fibers (CFRPs). This new approach can also greatly improve the diagnosis and monitoring of cutting tools and the optimization of cutting parameters. We do not claim to revolutionize machining theory but we intend to bring to light a new perspective for the analysis of machining processes.***OBJECTIVES:***The main goal of this research program is to provide new insights on the machinability of new advanced aerospace alloys, Carbon or Glass Fiber Reinforced Polymers (C/GFRP), tool wear modeling and analysis and develop a new surface analysis method and roughness parameters better adapted to composite materials.**