Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Surface integrity and fatigue of non-conventional machined Alloy 718
Tecnalia R&I, Advanced Manufacturing Department, San Sebastián, 20.009, Spain.
Tecnalia R&I, Advanced Manufacturing Department, San Sebastián, 20.009, Spain.
University of the Basque Country, Department of Mechanical Engineering, Spain.
Tecnalia R&I, Advanced Manufacturing Department, San Sebastián, 20.009, Spain.
Show others and affiliations
2019 (English)In: Journal of manufacturing processes, ISSN 1526-6125, Vol. 48, p. 44-50Article in journal (Refereed) Published
Abstract [en]

Alloy 718 is a high-strength, corrosion-resistant nickel chromium-based superalloy frequently used for applications, such as aerospace, marine, nuclear reactor and chemical industries, due to its outstanding inherent properties such as high strength and corrosion resistance at high temperatures together with good creep behaviour. Although, the use of conventional manufacturing processes is prevalent for their use on Alloy 718, alternative manufacturing technologies are gaining importance. This work compares the effects of alternative manufacturing processes, such as Abrasive water jet (AWJ), Wire Electrical Discharge Machining (WEDM) and ultrasound vibration assisted milling (UVAM) with conventional milling during the manufacture of Alloy 718 parts. Surface integrity, hardness, residual stress and fatigue strength obtained from these machining processes have been examined for cutting alloy 718. Results show that both residual stresses and surface roughness are correlated with fatigue strength. UVAM results shown an improvement on the surface integrity of the final workpiece. AWJ and WEDM show poorer results, further work on post-process technologies or process condition selection must be carry out to establish them as an alternative in Alloy 718 cutting operations.

Place, publisher, year, edition, pages
Elsevier, 2019. Vol. 48, p. 44-50
Keywords [en]
WEDM; AWJ; UVAM; Alloy 718; Fatigue; Surface integrity
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology; ENGINEERING, Manufacturing and materials engineering
Identifiers
URN: urn:nbn:se:hv:diva-12190DOI: 10.1016/j.jmapro.2019.09.041ISI: 000504919200004Scopus ID: 2-s2.0-85074301762OAI: oai:DiVA.org:hv-12190DiVA, id: diva2:1187098
Note

Funding: CLEAN-SKY program as financer of HIMMOVAL project 620134

Available from: 2018-03-02 Created: 2018-03-02 Last updated: 2020-11-10Bibliographically approved
In thesis
1. Surface integrity on post processed alloy 718 after nonconventional machining
Open this publication in new window or tab >>Surface integrity on post processed alloy 718 after nonconventional machining
2018 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

There is a strong industrial driving force to find alternative production technologies in order to make the production of aero engine components of superalloys even more efficient than it is today. Introducing new and nonconventional machining technologies allows taking a giant leap to increase the material removal rate and thereby drastically increase the productivity. However, the end result is to meet the requirements set for today's machined surfaces.The present work has been dedicated to improving the knowledge of how the non-conventional machining methods Abrasive Water Jet Machining, AWJM, Laser Beam Machining, LBM, and Electrical Discharge Machining, EDM, affect the surface integrity. The aim has been to understand how the surface integrity could be altered to an acceptable level. The results of this work have shown that both EDM and AWJM are two possible candidates but EDM is the better alternative; mainly due to the method's ability to machine complex geometries. It has further been shown that both methods require post processing in order to clean the surface and to improve the topography and for the case of EDM ageneration of compressive residual stresses are also needed.Three cold working post processes have been evaluated in order to attain this: shot peening, grit blasting and high pressure water jet cleaning, HPWJC. There sults showed that a combination of two post processes is required in order to reach the specified level of surface integrity in terms of cleaning and generating compressive residual stresses and low surface roughness. The method of high pressure water jet cleaning was the most effective method for removing the EDM wire residuals, and shot peening generated the highest compressive residual stresses as well as improved the surface topography.To summarise: the most promising production flow alternative using nonconventional machining would be EDM followed by post processing using HPWJC and shot peening.

Place, publisher, year, edition, pages
Trollhättan: University West, 2018. p. 92
Series
Licentiate Thesis: University West ; 20
Keywords
Alloy 718, Non-conventional machining, post processing, surface integrity, Microstructure, Residual stress, Electron back scattering diffraction, Material removal rate
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology; ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-12191 (URN)978-91-87531-72-9 (ISBN)978-91-87531-71-2 (ISBN)
Presentation
2018-03-07, C120, Högskolan Väst, Trollhättan, 10:15 (English)
Opponent
Supervisors
Available from: 2018-03-07 Created: 2018-03-02
2. High volumetric machining strategies for superalloy gasturbine components: Comparing conventional and nonconventional machining methods for efficient manufacturing
Open this publication in new window or tab >>High volumetric machining strategies for superalloy gasturbine components: Comparing conventional and nonconventional machining methods for efficient manufacturing
2020 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

There is a strong industrial driving force to find alternative manufacturing technologies in order to make the production of aero engine components of superalloys even more efficient than it is today. Introducing new and nonconventional machining technologies, as well as enhanced utilisation of today's high volumetric manufacturing, allows taking a leap to increase the material removal rate and the productivity. However, the final goal is to meet there quirements set for today's machined surfaces.The objective with the present work has been performed to show how the conventional, Milling, and the non-conventional machining methods, Abrasive Water Jet Machining, AWJM, Laser Beam Machining, LBM, and Electrical Discharge Machining, EDM, affect the surface integrity. This knowledge can beused to define and optimise different manufacturing alternatives for existing orfuture production.The results show that it is possible to use the rough milling to a greater extent if the impact on residuals stresses and deformation is used when determine the machining allowance. This could have a great impact on the productivity.

However, further improvement of the productivity requires an alternative method. For this reason, EDM and AWJM was evaluated and shown to be suitable alternatives to today's manufacturing methods, but both methods require post processing. The results showed that a combination of two post processes is required for addressing issues with residue, topography and residual stresses.The most promising and effective manufacturing strategy would be EDM or AWJM for rough machining followed by post processing either by finish millingor post processing by means of High-Pressure Water Jet Cleaning and shot peening. If EDM and AWJM are to be considered as finish machining operations, further development of the two methods are required.

Place, publisher, year, edition, pages
Trollhättan: University West, 2020. p. 121
Series
PhD Thesis: University West ; 40
Keywords
Alloy 718, High volumetric machining, Conventional and Nonconventional machining, Material removal rate, Post processing, surface integrity, Residual stress, Microstructure, Deformation
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology
Identifiers
urn:nbn:se:hv:diva-16010 (URN)978-91-88847-75-1 (ISBN)978-91-88847-74-4 (ISBN)
Public defence
2020-11-04, Albertssalen, 10:00 (English)
Opponent
Supervisors
Available from: 2020-11-11 Created: 2020-11-10 Last updated: 2020-11-10Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textScopus

Authority records

Holmberg, Jonas

Search in DiVA

By author/editor
Holmberg, Jonas
By organisation
Division of Subtractive and Additive Manufacturing
Manufacturing, Surface and Joining Technology

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 293 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf