GOALI/Collaborative Research: Thermomechanical Investigations of High Speed Machining of Aluminum

GOALI/合作研究：铝高速加工的热机械研究

• 批准号: 0223611
• 负责人: John Dolbow
• 金额: $ 15.07万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0223611&HistoricalAwards=false
• 关键词: GOALI; Collaborative; Research; Thermomechanical; Investigations

During the machining of metals, plastic deformation and friction lead to the production of heat in the workpiece, which results in complex deformation in the cutting zone. Recently, several numerical models of this highly coupled process have been produced in response to the increased interest in high speed machining. However, while a small number of researchers, in the past and recently, have examined temperature fields during cutting at low or traditional cutting speeds, few if any experimental studies exist that measure temperature fields in the work piece during cutting at high speeds, i.e. 20-100 m/s. It is important to characterize the thermal field in the cutting zone during high speed machining in order to characterize friction and wear characteristics in this area and to understand the heat generated there, which affects chip formation and possibly residual stress formation as well. Ultimately, such investigations should direct further advancement in materials development for high speed machining applications. In this work, infrared detectors are used to experimentally measure the temperature distribution at the surface of a workpiece during high-speed orthogonal cutting, and complex numerical models are developed to predict and understand the active mechanisms of deformation and failure. Finally, from these temperature measurements and models, the heat generated in the primary deformation zone is examined, characterized and related to the residual stress distribution in the workpiece. The main thrust is to better understand, and therefore reduce, the effects of residual stress on distortion of high-speed machined, thin walled components. The approach draws on the experience of experimental, numerical and industrial researchers to attack this difficult, economically relevant problem with a comprehensive experimental, theoretical and developmental approach. Specific benefits of the proposed work are: (1) Detailed understanding the interplay between finished product quality, material behavior and heat generation in high speed machining; (2) New efficient and accurate computational algorithms to model high-speed machining in order to facilitate full understanding of the observed interactions between tool, material and cut quality or residual stress formation; and (3) New directions in aluminum alloy design for high-speed cutting with emphasis on minimizing the effects of machining and alloy processing parameters on the formation of residual stresses in the finished product. Overall, an integrated materials-mechanics/modeling-experimentation approach to the problem will be used throughout the work leading to a multidisciplinary solution to the problem of residual stress distortion of parts machined at high-speed.

金属加工过程中，塑性变形和摩擦导致工件产生热量，导致切削区产生复杂的变形。最近，为了响应人们对高速加工日益增长的兴趣，已经产生了这种高度耦合过程的几个数值模型。然而，虽然过去和最近有少数研究人员检查了低速或传统切削速度切削过程中的温度场，但很少存在测量高速（即 20）切削过程中工件中温度场的实验研究。 -100米/秒。在高速加工过程中表征切削区域的热场非常重要，以便表征该区域的摩擦和磨损特性并了解那里产生的热量，这会影响切屑的形成以及可能的残余应力的形成。最终，此类研究应进一步推动高速加工应用材料的开发。在这项工作中，红外探测器用于实验测量高速正交切削过程中工件表面的温度分布，并开发复杂的数值模型来预测和理解变形和失效的主动机制。最后，根据这些温度测量和模型，对主变形区中产生的热量进行检查、表征并与工件中的残余应力分布相关。 主要目的是更好地了解残余应力对高速加工的薄壁部件变形的影响，从而减少其影响。该方法借鉴了实验、数值和工业研究人员的经验，通过综合实验、理论和开发方法来解决这一困难的、经济相关的问题。拟议工作的具体好处是：（1）详细了解高速加工中成品质量、材料行为和发热之间的相互作用； (2) 新的高效、准确的计算算法来模拟高速加工，以便于充分理解观察到的刀具、材料和切削质量或残余应力形成之间的相互作用； (3) 高速切削铝合金设计的新方向，重点是最大限度地减少机械加工和合金加工参数对成品残余应力形成的影响。 总体而言，整个工作将采用综合材料-力学/建模-实验方法来解决该问题，从而为高速加工零件的残余应力变形问题提供多学科解决方案。