Wear and failure mechanisms of SiAlON ceramic tools during high-speed turning of nickel-based superalloys

This paper explores the wear mechanisms of a Sialon ceramic tool in ultra high speed turning of Nickel-based alloy Inconel 718. Microstructures of the chips are also investigated. Stereo optical microscope and scanning electron microscope (SEM) are employed to observe worn surfaces of the tool produced by various wear mechanisms and morphological features of chips. In addition, the elemental compositions of wear products are evaluated by energy-dispersive X-ray spectroscopy (EDS). As a result of the study, wear mechanisms identified in the machining tests involve adhesive wear and abrasive wear. At the initial stage of cutting process, crater wear and flank wear are the main wear patterns. At the rapid wear stage, the SEM and EDS results showed that the adhered elements of Inconel 718 alloy on the tool rake face such as Ni, Fe and Cr accelerated the tool wear rate. Meanwhile, it was found that the chip morphology was serrated type under ultra high speed cutting condition, furthermore, the tendency of serration of the chip increased with the increase in cutting speed and feed rate.

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Study on the Machinability Characteristics of Superalloy K424 during High Speed Turning

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.188.636 ◽

2011 ◽

Vol 188 ◽

pp. 636-641 ◽

Cited By ~ 1

Author(s):

M.H. Xiao ◽

N. He ◽

L. Li ◽

B.G. Qiu ◽

Y. Su

Keyword(s):

High Speed ◽

Cutting Speed ◽

Depth Of Cut ◽

Machining Parameters ◽

Nitrogen Gas ◽

Ceramic Tools ◽

High Speed Turning ◽

Eds Analysis ◽

Nickel Based Alloy ◽

Notch Wear

The present paper is an attempt of an experimental investigation on the machinability of superalloy, K424 during high speed turning using different ceramic inserts under different cutting speed and cooling/lubricating condition. The effect of machining parameters on the tool wear was examined through SEM micrographs.The experimental results show that, round Al2O3＋SiCW KY4300R ceramic insert shows the best cutting performance in cutting the superalloy K424 , and it should be used in rather higher speed. Cold nitrogen gas is not recommended when machining nickel-based alloy with ceramic tools. SEM and EDS analysis shows that the ceramic tool was severely controlled by tool nose and depth-of-cut notch wear, followed by flaking and chipping.

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ANALYSIS OF SPECIFIC CUTTING ENERGY IN HIGH SPEED TURNING OF INCONEL 718 BY USING CERAMIC TOOLS

International Journal of Advance Engineering and Research Development ◽

10.21090/ijaerd.020159 ◽

2015 ◽

Vol 2 (01) ◽

Keyword(s):

Inconel 718 ◽

High Speed ◽

Specific Cutting Energy ◽

Ceramic Tools ◽

High Speed Turning ◽

Cutting Energy

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Technical Performance of High Pressure and High Temperature Processed TiC Ceramic Tools

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1048 ◽

2012 ◽

Vol 727-728 ◽

pp. 1048-1052

Author(s):

Guerold Sergueevitch Bobrovinitchii ◽

Ana Lucia D. Skury ◽

Sérgio Neves Monteiro ◽

Márcia G. Azevedo

Keyword(s):

Thermal Stability ◽

High Pressure ◽

High Temperature ◽

High Speed ◽

Turning Operations ◽

Ceramic Tools ◽

Technical Performance ◽

High Speed Turning

Non-oxide covalent ceramics such as TiC and TiN display hardness and thermal stability that favor their use as cermet insert for high speed turning operations. The objective of this work was to assess the properties of the TiC combined with W-Mo as binding matrix. The cermet sintering was carried out inside a toroidal anvil type of high pressure device up to 1.0 GPa of pressure and temperatures up to 1800°C. It was found that at 1400°C the Mo reacts with TiC forming Mo2C while at 1800°C the reaction with W forms WC. Moreover, the cermets density reaches 98% of the theoretically calculated value with strength of 942 MPa and Rockwell A hardness of 94. Efficient turning parameters are reported for machining operation using these cermets as tools insert.

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