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Plastic Deformation and Residual Stress in High Speed Turning of AD730™ Nickel-based Superalloy with PCBN and WC Tools

Chen, Z. LU ; Zhou, J. M. LU ; Peng, R. L. ; M'Saoubi, R. ; Gustafsson, D. ; Palmert, F. and Moverare, J. (2018) 4th CIRP Conference on Surface Integrity, CIRP CSI 2018 In Procedia CIRP 71. p.440-445
Abstract

A higher gas turbine efficiency can be achieved by increasing the operating temperature in hot sections. AD730™ is a recently-developed wrought/cast nickel-based superalloy which can maintain excellent mechanical properties above 700. However, machining of AD730™ could be a difficult task like other nickel-based superalloys. Therefore, studies are needed with respect to the machinability of this new alloy. In this paper, high-speed turning was performed on AD730™ using polycrystalline cubic boron nitride (PCBN) tools and coated tungsten carbide (WC) tools at varied cutting speeds. The surface integrity was assessed in two important aspects, i.e., surface and sub-surface plastic deformation and residual stresses. The PCBN tools generally... (More)

A higher gas turbine efficiency can be achieved by increasing the operating temperature in hot sections. AD730™ is a recently-developed wrought/cast nickel-based superalloy which can maintain excellent mechanical properties above 700. However, machining of AD730™ could be a difficult task like other nickel-based superalloys. Therefore, studies are needed with respect to the machinability of this new alloy. In this paper, high-speed turning was performed on AD730™ using polycrystalline cubic boron nitride (PCBN) tools and coated tungsten carbide (WC) tools at varied cutting speeds. The surface integrity was assessed in two important aspects, i.e., surface and sub-surface plastic deformation and residual stresses. The PCBN tools generally showed better performance compared with the WC tools since it led to reduced machining time without largely compromising the surface integrity achieved. The optimal cutting speed was identified in the range of 200-250 m/min when using the PCBN tools, which gives rise to a good combination of machining efficiency and surface integrity. The further increase of the cutting speed to 300 m/min resulted in severe and deep plastic deformation. Meanwhile, a continuous white layer was formed at the machined surface. When turning with the WC tools, the increased cutting speed from 80 m/min to 100 m/min showed very little effect with respect to the plastic deformation on the machined surface. It was found that tensile residual stresses were developed on all machined surfaces no matter when the PCBN or WC tools were used, and the surface tension was generally increased with increasing cutting speed. The tensile layer might need to be modified by e.g., post-machining surface treatments such as shot peening, if taking good fatigue performance into consideration.

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Please use this url to cite or link to this publication:
author
; ; ; ; ; and
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
AD730™, High-speed turning, Nickel-based superalloy, Plastic deformation, Residual stress
host publication
Procedia CIRP
series title
Procedia CIRP
volume
71
pages
6 pages
conference name
4th CIRP Conference on Surface Integrity, CIRP CSI 2018
conference location
Tianjin, China
conference dates
2018-07-11 - 2018-07-13
external identifiers
  • scopus:85051255253
ISSN
2212-8271
DOI
10.1016/j.procir.2018.05.051
language
English
LU publication?
yes
id
a3d28dfa-d36b-49aa-ab70-8e3df6a8295d
date added to LUP
2018-09-13 10:35:49
date last changed
2022-04-25 17:05:59
@inproceedings{a3d28dfa-d36b-49aa-ab70-8e3df6a8295d,
  abstract     = {{<p>A higher gas turbine efficiency can be achieved by increasing the operating temperature in hot sections. AD730™ is a recently-developed wrought/cast nickel-based superalloy which can maintain excellent mechanical properties above 700. However, machining of AD730™ could be a difficult task like other nickel-based superalloys. Therefore, studies are needed with respect to the machinability of this new alloy. In this paper, high-speed turning was performed on AD730™ using polycrystalline cubic boron nitride (PCBN) tools and coated tungsten carbide (WC) tools at varied cutting speeds. The surface integrity was assessed in two important aspects, i.e., surface and sub-surface plastic deformation and residual stresses. The PCBN tools generally showed better performance compared with the WC tools since it led to reduced machining time without largely compromising the surface integrity achieved. The optimal cutting speed was identified in the range of 200-250 m/min when using the PCBN tools, which gives rise to a good combination of machining efficiency and surface integrity. The further increase of the cutting speed to 300 m/min resulted in severe and deep plastic deformation. Meanwhile, a continuous white layer was formed at the machined surface. When turning with the WC tools, the increased cutting speed from 80 m/min to 100 m/min showed very little effect with respect to the plastic deformation on the machined surface. It was found that tensile residual stresses were developed on all machined surfaces no matter when the PCBN or WC tools were used, and the surface tension was generally increased with increasing cutting speed. The tensile layer might need to be modified by e.g., post-machining surface treatments such as shot peening, if taking good fatigue performance into consideration.</p>}},
  author       = {{Chen, Z. and Zhou, J. M. and Peng, R. L. and M'Saoubi, R. and Gustafsson, D. and Palmert, F. and Moverare, J.}},
  booktitle    = {{Procedia CIRP}},
  issn         = {{2212-8271}},
  keywords     = {{AD730™; High-speed turning; Nickel-based superalloy; Plastic deformation; Residual stress}},
  language     = {{eng}},
  pages        = {{440--445}},
  series       = {{Procedia CIRP}},
  title        = {{Plastic Deformation and Residual Stress in High Speed Turning of AD730™ Nickel-based Superalloy with PCBN and WC Tools}},
  url          = {{http://dx.doi.org/10.1016/j.procir.2018.05.051}},
  doi          = {{10.1016/j.procir.2018.05.051}},
  volume       = {{71}},
  year         = {{2018}},
}