Predicting chip and non-chip formation when micromachining Ti-6Al-4V titanium alloy

The advanced machining of components used in miniature unmanned aircraft vehicles is the focus of this study. The finite element method (FEM) is used to predict forces and temperatures using cutting tool inserts with a thin nanostructured film of high integrity. Similarity models are used to validate the finite element results and to understand the influence of micromachining parameters on cutting temperatures generated when machining Al 380-0 alloy. The predicted results are compared to experimental forces and temperatures using a three-dimensional piezoelectric function dynamometer and a short-range infra-red wavelength thermal camera. Nanostructured thin layer coatings lower machining forces and temperatures, which are validated through FEM predictions and experimental observations. The experimental results suggest that increasing the cutting tool’s rake angle at higher depths of cut will reduce cutting temperatures, which are predicted using the similarity models for micromachining.

Section: Experimental Procedures and Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Advanced machining of miniature unmanned aircraft vehicle components using nanostructured cutting tools

Jackson

Burgess

Whitfield

et al. 2020

“…The following sections describe the calculation of forces and temperatures in micromilling of AISI SAE 1020 hypoeutectoid steel (~0.2 wt.% carbon in iron) using methods described in references. [10][11][12]22,24,28,29…”

Section: Machining Analysismentioning

confidence: 99%

“…11 During macroscale cutting, the leading tool edge encounters bulk material (composite structures), and therefore, avoids contact with hard particles, while a microcutting edge encounters individual grains ensuring contact with soft and hard particles. 12 The results of Ikawa et al 13 suggest that there is a critical minimum depth of cut below which chips do not form. The analysis of Yuan et al 14 indicates that chip formation is not possible if the depth of cut is less than 20%-40% of the cutting edge radius (h c < (0.2 r c -0.4 r c )).…”

Section: Introductionmentioning

confidence: 99%

Similarity and difference in machining at mixed scales using nanostructured coated tools milling hypoeutectoid carbon steel

Jackson,

Robinson,

Whitfield

et al. 2023

There are similarities and differences when machining at the microscale and macroscale. One difference is the lack of significant heat generated at the microscale, which means that thermal barrier coatings are largely redundant. However, the mechanisms of wear are similar and different depending on machining parameters. In this study, it is discovered that nanostructured coatings play different roles at mixed scales, which are experimentally determined by measuring tool wear, chemical diffusion, temperature, and forces. The main findings show that macroscale wear is thermal in nature and that microscale wear is primarily tribological. The principal conclusions focus on redesigning microtools and nanostructured coatings to eliminate wear, developing standards that describe the action of microtools, and understanding how to calculate the minimum chip thickness that guarantees the formation of chips rather than burrs.

“…The metal cutting process is a complex operation involving physical and chemical effects such as plastic deformation, frictional interactions between the tool edge and component, thermal–mechanical couplings and chip and non-chip formation mechanisms. 2 , 3 Digital simulation of the microturning process aids the understanding of machining and can instruct the engineer to design machining cycles that minimize waste and reduce cost. Therefore, a significant effort is spent on the development of appropriate analytical digital models.…”

Section: Introductionmentioning

confidence: 99%

Microturning of landing gear components used in miniature unmanned aircraft vehicles

Jackson

Burgess

2018

The microturning of landing gear components used in miniature unmanned aircraft vehicles is described in this article. The finite element method (FEM) is used to predict variables such as microturning forces and temperatures at two different levels of roughing cut (1 and 3 mm depth of cut) with variable geometry cutting tool inserts. The predicted results are compared to experimentally determined magnitudes of forces and temperatures using a dynamometer and an infrared thermal camera. The results show that tool inserts with novel chip breaker functions reduce the magnitude of the machining forces and temperatures predicted using the FEM and validated by performing controlled experiments using Al-380 aluminum alloys machined with polycrystalline diamond-coated cutting tool inserts.