Master of Engineering Science
Mechanical and Materials Engineering
V-groove microstructures have found numerous functionalization applications in mechanical, electronic, photonic, biomechanical and optical components. However, despite their wide use, the manufacturing processes associated with their fabrication are limited to axial strategies with a constant depth of cut that do not allow the control of the cutting force and cutting time, and therefore leading to significant micro-burrs as well as an inability to fabricate high aspect ratio grooves. The current thesis addresses this problem with the development of three cutting strategies that make use of a single point cutting process. The study to be detailed herein includes analytical, numerical and experimental approaches with respect to cross-sectional area calculations, tool path planning, finite element modelling as well as experimental measurements of the cutting force and surface roughness. The results revealed that a relationship exists between the number of passes/depth of cut and the magnitude of cutting force as measured along the feed direction as well as the existence of a relationship between chip thickness and surface quality. The developed cutting strategies proved to be efficient in manufacturing of symmetrical V-groove microstructures and augmented the field of micromachining with alternative cutting strategies.
Summary for Lay Audience
The increase in convenience and value of many industrial and household products due to their size and weight reduction over the years has triggered rapid development of the micromachining field. The functionalization of these products - a procedure through which microstructures are added on a surface of the product to enhance some of its properties such as optical and thermal - receives a growing attention in micromachining because of the enhanced capabilities added to the part’s surface. Among the different microstructures used for functionalization purposes, V-grooves stand out due to their applications in the enhancement of many components in different fields. V-groove structures have found numerous applications in mechanical, electronic, photonic, biomechanical and optical components. However, despite their wide use, their manufacturing processes are limited to an axial cutting strategy with a constant depth of cut that does not allow controlling cutting force and cutting time, and therefore it leads to significant micro-burrs and inability to fabricate high aspect ratio grooves. To address these issues, three cutting strategies are developed in this thesis, having each two implementations for cutting: constant chip thickness and constant cutting area. The three strategies are divided into one axial and two non-axial cutting strategies. The development of each cutting strategy on its two implementations included a cutting mechanics model for material removal, post-processor, finite element analysis and experimental verification for a single groove. The results of this work revealed that a relationship exists between the number of passes/depth of cut and the magnitude of cutting force as measured along the feed direction as well as the existence of a relationship between the chip thickness and surface quality. The developed cutting strategies proved to be efficient in manufacturing of a single ultraprecise symmetrical V-groove microstructure with areal surface quality and have improved the micromachining field with alternative cutting strategies.
Joao, Delfim A C, "Strategies for Ultraprecise Single Point Cutting of V-grooves" (2020). Electronic Thesis and Dissertation Repository. 6978.