Advances in Rotary Ultrasonic-Assisted Machining

O’Toole, Lorcan; Kang, Chris; Fang, Fengzhou

doi:10.1007/s41871-019-00053-3

Cited by 44 publications

(17 citation statements)

References 121 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Channel length was also fixed at 14 mm (Table 2). Therefore, testing this range of widths assesses the feasibility of modern manufacturing methods and their suitability to these devices within this operating window [28][29][30][31].…”

Section: Variation In Channel Widthmentioning

confidence: 99%

Numerical Analysis of Microchannels Designed for Heat Sinks

McCormack

Zhang

2021

Nanomanuf Metrol

Self Cite

View full text Add to dashboard Cite

Conjugate heat transfer is numerically investigated using a three-dimensional computational fluid dynamics approach in various microchannel geometries to identify a high-performance cooling method for piezoelectric ceramic stacks and spindle units in high-precision machines. Straight microchannels with rectangular cross sections are first considered, showing the performance limitations of decreasing the size of the microchannels, so other solutions are needed for high applied heat fluxes. Next, many microchannel designs, focusing on streamwise geometric variation, are compared to straight channels to assess their performances. Sinusoidally varying channels produce the highest heat transfer rates of those studied. Thus, their optimization is considered at a channel width and height of 35 and 100 μm, respectively. Heat transfer increases as the amplitude and spatial frequencies of the channels increase due to increased interfacial surface area and enhanced Dean flow. The highest performance efficiencies are observed at intermediate levels of amplitude and frequency, with efficiency decreasing as these geometric parameters are increased further at the onset of flow separation. The sinusoidal channel geometries are then optimized with respect to minimizing the system’s pressure drop for all applied heat fluxes between 5690 and 6510 kW/m2. Doing so created an optimal geometry curve and showed that all geometries in this region had amplitudes close to 40 μm. Therefore, imposing a fixed heat flux requirement for a case study of cooling piezoelectric ceramics, the optimized sinusoidal geometry decreases the system pressure drop by 79% relative to a straight channel while maintaining a larger minimum feature size.

show abstract

Section: Variation In Channel Widthmentioning

confidence: 99%

Numerical Analysis of Microchannels Designed for Heat Sinks

McCormack

Zhang

2021

Nanomanuf Metrol

Self Cite

View full text Add to dashboard Cite

show abstract

“…This leads to increased tool and machine tool life, improved surface quality, effective chip management, and more efficient machining. Other desirable properties of a cutting fluid are being nontoxic and safe to handle, while preventing any chemical corrosion or degradation of the tools or components [ 158 ]. Cutting fluids can be applied to the working area in various ways, such as by compressed air as minimum quantity mist, in a flooding process, and at high and low pressure.…”

Section: Process Inputsmentioning

confidence: 99%

“…However, the application of micro-milling in the mold, optics, and biomedical industries requires that this process must be suitable for machining typical difficult-to-machine materials, from very hard and wear resistant metallic alloys to very brittle ceramics or deliquescent crystal materials. One of the major efforts directed toward processing these difficult-to-machine materials has been the application of μRUAM [ 158 ]. This process applies an ultrasonic frequency vibration in the range of 20–100 kHz with an amplitude between 5 μm and 50 μm at the tool tip in one or more directions, e.g., axially or radially.…”

Section: Advanced Processesmentioning

confidence: 99%

Precision micro-milling process: state of the art

2020

Self Cite

View full text Add to dashboard Cite

Micro-milling is a precision manufacturing process with broad applications across the biomedical, electronics, aerospace, and aeronautical industries owing to its versatility, capability, economy, and efficiency in a wide range of materials. In particular, the micro-milling process is highly suitable for very precise and accurate machining of mold prototypes with high aspect ratios in the microdomain, as well as for rapid micro-texturing and micro-patterning, which will have great importance in the near future in bio-implant manufacturing. This is particularly true for machining of typical difficult-to-machine materials commonly found in both the mold and orthopedic implant industries. However, inherent physical process constraints of machining arise as macro-milling is scaled down to the microdomain. This leads to some physical phenomena during micro-milling such as chip formation, size effect, and process instabilities. These dynamic physical process phenomena are introduced and discussed in detail. It is important to remember that these phenomena have multifactor effects during micro-milling, which must be taken into consideration to maximize the performance of the process. The most recent research on the micro-milling process inputs is discussed in detail from a process output perspective to determine how the process as a whole can be improved. Additionally, newly developed processes that combine conventional micro-milling with other technologies, which have great prospects in reducing the issues related to the physical process phenomena, are also introduced. Finally, the major applications of this versatile precision machining process are discussed with important insights into how the application range may be further broadened.

show abstract

“…The glass ceramic Macor is increasingly implemented in aerospace engineering [35,36] and high precision engineering applications [37,38]. The viscoelastic property of Macor was reported by Bagdassarov [39], together with the internal friction and the shear modulus.…”

Section: Introductionmentioning

confidence: 99%

Loading Mode and Lateral Confinement Dependent Dynamic Fracture of a Glass Ceramic Macor

Zhang

Townsend

Petrinić

et al. 2022

J. dynamic behavior mater.

View full text Add to dashboard Cite

A systematic comparison of the tensile and compressive response of glass ceramic Macor, with zero porosity and low density, is carried out by using flattened Brazilian disk and cylindrical specimen from quasi-static to dynamic loading conditions. The experiments were performed on a screw driven Zwick machine and an in-house built split Hopkinson bar synchronized with a high speed photographic system. Likewise, the loading rate dependent fracture toughness is also investigated by using a notched semi-circular Brazilian disk. A digital image correlation technique is adopted to assist in the monitoring of strain field, crack initiation and propagation under dynamic loading conditions. Both tensile and compressive strength show loading rate dependencies, however, the static and dynamic tensile strengths are only 20% of the compressive strengths without confinement and less than 10% of the confined compressive strength. The microstructural characterization reveals the fracture mechanisms in unconfined Macor are predominantly transgranular with mica platelets and cleavage planes, which are influenced by the loading mode and loading rate. However, the Macor with confinement shows ductile fracture micrographs with a shear localization zone consisting of fine particles. With the use of Macor ceramic as a model material, the paper presents an economical approach to investigate the loading mode and pressure dependent failure of ceramic materials. This will support the characterization of dynamic properties of current and future developed advanced ceramics for demanding applications in the aero engine.

show abstract

Advances in Rotary Ultrasonic-Assisted Machining

Cited by 44 publications

References 121 publications

Numerical Analysis of Microchannels Designed for Heat Sinks

Numerical Analysis of Microchannels Designed for Heat Sinks

Precision micro-milling process: state of the art

Loading Mode and Lateral Confinement Dependent Dynamic Fracture of a Glass Ceramic Macor

Contact Info

Product

Resources

About