التفاصيل البيبلوغرافية
| العنوان: |
Modeling of Precipitation by Structural Phase-Field Crystal Method |
| Alternate Title: |
Modellering av utfällningar genom structural fasfältskristall method |
| المؤلفون: |
Holmberg-Kasa, Jacob |
| بيانات النشر: |
Malmö universitet, Institutionen för materialvetenskap och tillämpad matematik (MTM), 2021. |
| سنة النشر: |
2021 |
| المجموعة: |
DiVA Archive at Upsalla University |
| مصطلحات موضوعية: |
strain-age cracking, SAC, structural phase-field crystal, XPFC, nickel-based alloys, precipitation, Manufacturing, Surface and Joining Technology, Bearbetnings-, yt- och fogningsteknik, Metallurgy and Metallic Materials, Metallurgi och metalliska material, Condensed Matter Physics, Den kondenserade materiens fysik |
| الوصف: |
Nickel-based alloys are used in components such gas turbines within the aerospace industry and electric power generation due to its high tensile, rapture and creep strength. Increasing the efficiency of gas turbines are crucial to reduce emissions within the aerospace industry and increasing power gain for electric power generation. Innovation to increase the efficiency relies in part on the development of new nickel-based alloys with beneficial material properties. But also on stable and predictable material behavior during processing and post-processing of the components in the gas turbine. In two prominent material processing fields of precipitation hardened nickel-based alloys, additive manufacturing and welding, strain-age cracking (SAC) is a common phenomenon. SAC is a solid state phenomenon that generally occurs in alloys strengthened with 𝛾′, L12(Pm3m), or 𝛾′′, D022(I4/mmm), phase precipitates during post weld heat treatment or reheating where it manifests as intergranular cracking. Even though the existence of SAC has been known for several decades, its dominant mechanisms are still under considerable debate and the undertaken modeling efforts to gain insight on the phenomenon are virtually non-existent. This study aims to clarify the dominant mechanisms behind strain-age cracking. Breaching this gap would allow for new development for nickel-based alloys within both additive manufacturing and welding. To that extent the goal of this study is to provide tools to aid in clarifying the dominant mechanisms behind strain-age cracking. This is done by implementing the recently developed structural phase-field crystal (XPFC) model and examining the capabilities to model a precipitation event during reheating for a reference binary alloy in two dimensions. To evaluate the strain because of precipitation, a simple method based on the principles of neutron and synchrotron strain scanning is outlined and tested on the limited precipitation event achieved within the study. The XPFC model is capable of modeling precipitation with some restrictions that need further development with extended computational recourses. Lastly, the possibilities to extend the implemented XPFC model to cover nickel-based alloys is discussed. |
| Original Identifier: |
oai:DiVA.org:mau-47187 |
| نوع الوثيقة: |
Text |
| وصف الملف: |
application/pdf |
| اللغة: |
English |
| الاتاحة: |
http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-47187 |
| Rights: |
info:eu-repo/semantics/openAccess |
| رقم الانضمام: |
edsndl.UPSALLA1.oai.DiVA.org.mau.47187 |
| قاعدة البيانات: |
Networked Digital Library of Theses & Dissertations |