TU Darmstadt / ULB / TUbiblio

Local fracture toughness and residual stress measurements on NiAl bond coats by micro cantilever and fib-based bar milling tests

Webler, R. and Krottenthaler, M. and Neumeier, S. and Durst, Karsten and Göken, M. (2013):
Local fracture toughness and residual stress measurements on NiAl bond coats by micro cantilever and fib-based bar milling tests.
In: Proceedings of the International Symposium on Superalloys, Hobroken, pp. 93-102, DOI: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84885926632&partnerID=40&md5=cfda36f793747faa202f38e4f0e327f9,
[Book Section]

Abstract

The mechanical behavior of bond coats depends on their chemical composition. Important for the mechanical behavior is the Al content of β-NiAl based coatings. Additionally, internal stresses are present and change during thermal cycling. Therefore bond coats with different Ni and Al content in the as-coated and thermally cycled state are investigated. For the first time, new small scaled methods are used to obtain fracture toughness and internal stresses of real bond coat systems. Micro cantilever bending and stress relaxation tests were performed on a local scale by employing focused ion beam milling. Additionally, the influence of NiAl composition on Young's modulus and hardness is studied by nanoindentation. Results show an increase of Young's modulus with Al content. In off-stoichiometric NiAl a higher hardness and fracture toughness than in binary NiAl is found. The internal stresses change from tensile in as-coated to compressive stresses in thermally cycled bond coats, respectively.

Item Type: Book Section
Erschienen: 2013
Creators: Webler, R. and Krottenthaler, M. and Neumeier, S. and Durst, Karsten and Göken, M.
Title: Local fracture toughness and residual stress measurements on NiAl bond coats by micro cantilever and fib-based bar milling tests
Language: English
Abstract:

The mechanical behavior of bond coats depends on their chemical composition. Important for the mechanical behavior is the Al content of β-NiAl based coatings. Additionally, internal stresses are present and change during thermal cycling. Therefore bond coats with different Ni and Al content in the as-coated and thermally cycled state are investigated. For the first time, new small scaled methods are used to obtain fracture toughness and internal stresses of real bond coat systems. Micro cantilever bending and stress relaxation tests were performed on a local scale by employing focused ion beam milling. Additionally, the influence of NiAl composition on Young's modulus and hardness is studied by nanoindentation. Results show an increase of Young's modulus with Al content. In off-stoichiometric NiAl a higher hardness and fracture toughness than in binary NiAl is found. The internal stresses change from tensile in as-coated to compressive stresses in thermally cycled bond coats, respectively.

Title of Book: Proceedings of the International Symposium on Superalloys
Place of Publication: Hobroken
Divisions: 11 Department of Materials and Earth Sciences
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences > Material Science > Physical Metallurgy
Event Title: 12th International Symposium on Superalloys, Superalloys 2012
Event Location: Seven Springs, PA
Event Dates: 9.-13. September 2012
Date Deposited: 19 Jul 2018 12:14
DOI: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84885926632&partnerID=40&md5=cfda36f793747faa202f38e4f0e327f9
Export:

Optionen (nur für Redakteure)

View Item View Item