Crater Wear of TiCN Cermets in Conventional Machining

Polycrystalline diamond (PCD) tools are widely used in industry due to their outstanding physical properties. However, the ultra-high hardness of PCD significantly limits the machining efficiency of conventional abrasive grinding processes, which are utilized to manufacture PCD tools. In contrast, electrical discharge grinding (EDG) has significantly higher machining efficiency because of its unique material removal mechanism. In this study, the quality and performance of PCD tools machined by abrasive grinding and EDG were investigated. The performance of cutting tools consisted of different PCD materials was tested by high-speed turning of titanium alloy Ti6Al4V. Flank wear and crater wear were investigated by analyzing the worn profile, micro morphology, chemical decomposition, and cutting forces. The results showed that an adhesive-abrasive process dominated the processes of flank wear and crater wear. Tool material loss in the wear process was caused by the development of thermal cracks. The development of PCD tools’ wear made of small-sized diamond grains was a steady adhesion-abrasion process without any catastrophic damage. In contrast, a large-scale fracture happened in the wear process of PCD tools made of large-sized diamond grains. Adhesive wear was more severe on the PCD tools machined by EDG.

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A polymer chip-integrable piezoelectric micropump with low backpressure dependence

RSC Advances ◽

10.1039/c5ra08819d ◽

2015 ◽

Vol 5 (62) ◽

pp. 49996-50000 ◽

Cited By ~ 7

Author(s):

A. J. Conde ◽

A. Bianchetti ◽

F. E. Veiras ◽

A. Federico ◽

J. M. Cabaleiro ◽

...

Keyword(s):

Microfluidic Chips ◽

Conventional Machining

A polymer piezoelectric micropump fabricated with conventional machining methods that can be embedded in laminated microfluidic chips.

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Cutting Tool Wear and Mechanisms of Chip Formation During High-Speed Machining of Compacted Graphite Iron

ASME/STLE 2007 International Joint Tribology Conference, Parts A and B ◽

10.1115/ijtc2007-44026 ◽

2007 ◽

Author(s):

Niniza S. P. Dlamini ◽

Iakovos Sigalas ◽

Andreas Koursaris

Keyword(s):

Tool Wear ◽

Surface Finish ◽

Failure Criterion ◽

Cutting Tool ◽

Flank Wear ◽

Cutting Tools ◽

Compacted Graphite Iron ◽

Crater Wear ◽

Compacted Graphite ◽

Cutting Speeds

Cutting tool wear of polycrystalline cubic boron nitride (PcBN) tools was investigated in oblique turning experiments when machining compacted graphite iron at high cutting speeds, with the intention of elucidating the failure mechanisms of the cutting tools and presenting an analysis of the chip formation process. Dry finish turning experiments were conducted in a CNC lathe at cutting speeds in the range of 500–800m/min, at a feed rate of 0.05mm/rev and depth of cut of 0.2mm. Two different tool end-of-life criteria were used: a maximum flank wear scar size of 0.3mm (flank wear failure criterion) or loss of cutting edge due to rapid crater wear to a point where the cutting tool cannot machine with an acceptable surface finish (surface finish criterion). At high cutting speeds, the cutting tools failed prior to reaching the flank wear failure criterion due to rapid crater wear on the rake face of the cutting tools. Chip analysis, using SEM, revealed shear localized chips, with adiabatic shear bands produced in the primary and secondary shear zones.

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Experimental Analysis of Process Parameters to Manufacture Micro-Cavities by Micro-Milling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.498.91 ◽

2012 ◽

Vol 498 ◽

pp. 91-96 ◽

Cited By ~ 1

Author(s):

J. Gomar ◽

A. Amaro ◽

E. Vázquez ◽

J. Ciurana ◽

C. Rodríguez

Keyword(s):

Automotive Industry ◽

Micro Milling ◽

Geometric Features ◽

Milling Machine ◽

Machining Processes ◽

New Approach ◽

Biomedical Field ◽

Dimensional Errors ◽

Conventional Machining ◽

Potential Opportunity

The use of conventional machining processes has been subject to important decline probably due to the increment in the use of emerging technologies. Therefore, the main applications of these traditional processes, such as automotive industry, are in crisis. In order to have a chance to compete successfully in the new trends, the machining industry must meet the needs of alternative sectors such as biomedical field. The aim of this study is to prove the capacity of micro-milling, by machining complex micro-cavities on aluminum workpiece using a conventional milling machine. Results are obtained by evaluating accuracy and geometric features. This study finds that the feed per tooth is a significant factor in order to obtain better results. The use of coolant increases the tool wear and therefore dimensional errors. This scope is a potential opportunity to reutilize the conventional machines from a new approach.

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Application of New Abrasives and their Quality Parameters

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.261.181 ◽

2017 ◽

Vol 261 ◽

pp. 181-188 ◽

Cited By ~ 1

Author(s):

Frantisek Holešovsky ◽

Martin Bartos ◽

Milan Dian ◽

Jan Řehoř

Keyword(s):

Quality Parameters ◽

Abrasive Grains ◽

Individual Grains ◽

Conventional Machining

Recent years have highly been productive in terms of development of both conventional machining technology, but in workpiece surfaces finishing, as well. The overall trend is heading towards increasing accuracy and quality of the manufactured components for machinery and equipment. In a range of finishing abrasive technologies there has been known the introduction of microcrystalline corundum, modification of tools with these abrasive grains, including sintered tools. This development continues and the latest trend is the development of pyramidal grain the Cubitron II. How individual grains behave during operation and how we can use their properties in comparison to classic white corundum still remains complicated matter. The behaviour of selected abrasives has been described in the submitted article.

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Wear Behavior of Carbide Inserts in Face Milling TA19 Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.426.339 ◽

2012 ◽

Vol 426 ◽

pp. 339-343 ◽

Cited By ~ 3

Author(s):

Qiu Lin Niu ◽

X.J. Cai ◽

Zhi Qiang Liu ◽

Ming Chen ◽

Qing Long An

Keyword(s):

Titanium Alloy ◽

Wear Behavior ◽

Cutting Speed ◽

Aircraft Engine ◽

Face Milling ◽

Depth Of Cut ◽

Cnc Milling ◽

Crater Wear ◽

Stable Conditions ◽

Carbide Inserts

As a typical high strength material, titanium alloy Ti-6Al-2Sn-4Zr- 2Mo-0.1Si (TA19) is used to manufacturing the compressor power-brake of aircraft engine and the aircraft skin. All the machining experiments were carried out on a CNC-milling center under the stable conditions of cutting speed, feed rate, and depth of cut. The performance and wear mechanisms of coated- and uncoated carbide tools have been investigated in this paper to evaluate the machinability of TA19 in face milling. The three tools used were PVD-TiN+TiAlN, CVD-TiN+Al2O3+TiCN and uncoated carbide inserts. The results indicated that PVD coating had the best performance than other tool materials in milling titanium alloy TA19, and the cutting force and the wear value were the smallest than that for CVD-coated and uncoated tools. The failure types of PVD-, CVD- and uncoated inserts were the crater wear and micro tipping; the crater wear and tipping; tipping. Abrasive wear and adherent wear were the predominant mechanism of PVD-TiN+TiAlN carbide insert in face milling TA19 alloy. For CVD- and uncoated carbide, adherent wear was predominant.

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Study on the effective discharge energy mechanism of vertical ultrasonic vibration assisted EDM processing

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/09544054211028527 ◽

2021 ◽

pp. 095440542110285

Author(s):

Yinghuai Dong ◽

Guangyan Li ◽

Yan Wang ◽

Jianbao Song ◽

Shuo Yang ◽

...

Keyword(s):

Ultrasonic Vibration ◽

Theoretical Research ◽

Discharge Energy ◽

Movement Path ◽

Energy Mechanism ◽

Effective Discharge ◽

Parameter Matching ◽

Discharge Gap ◽

Conventional Machining

Compared to traditional EDM processing, UEDM (Ultrasonic Vibration Assisted EDM) have a great improvement in optimizing discharge environment. In this study, ultrasonic vibration is attached to the electrode. According to the relative positional relationship between the movement path of the electrode tip and the discharge gap, four working states of UEDM are defined. The four working states are the path within the discharge gap, the path in contact with the edge of the discharge gap, part of the electrode end path outside the discharge gap, and the path in contact with the workpiece, respectively. States are analyzed from the effective discharge energy and discharge frequency. A mathematical model for effective discharge energy and surface roughness is established for two conventional working states. The correctness of the theoretical research is verified by experiments. As the experiment results shown, the influence of ultrasonic amplitude on the energy of UEDM is primary, while frequency is secondary. A working state with better discharge stability and higher discharge energy when the electrode end path is in contact with the edge of the discharge gap. In the first three conventional machining states, the surface quality of the workpiece increases with the increase of ultrasonic amplitude and frequency. The study can provide scientific guidance for parameter matching of UEDM.

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