Cracking processes during creep test of ŻS6U superalloy with aluminium coatings

• Autorzy: Cieśla, M. , Swadźba, L.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The paper presents the evaluation of the influence of aluminium layers used as protective coatings of aircraft turbine engine blades upon durability of ŻS6U nickel base superalloy under the conditions of short time creep. The conditions of cracks formation and growth in specimens with aluminium coatings have been analysed while taking into account the microstructure properties of coatings as well as the microstructure of specimen core material. Design/methodology/approach: The creep tests have been performed on MTS apparatus in the conditions corresponding to the extreme operating conditions of aircraft engine blades. The specimens were heated in a resistance furnace up to the temperature of 950ºC and then constant axial force was applied which induced stress σo=300 MPa in their cross-section. Findings: The obtained results have proved a significant influence of the type, protective coating thickness and the specimen core structure upon the secondary creep rate. Research limitations/implications: To ensure the most effective use of aluminium protective coatings it is important to understand the creep mechanisms in temperature lower than DBTT (ductile brittle transition temperature). Therefore, it is necessary to perform some creep tests in temperatures much lower than 900ºC. Practical implications: The obtained results could constitute the base for suggesting the guidelines on selecting proper aluminium coatings for specific designs of aircraft engine blades. Originality/value: It has been found that the reduction of creep durability of specimens made of ŻS6U alloy with diffusive aluminium coatings is caused by the reduction of the lateral surface of specimens core, which effectively transfers loads in creep tests.

Słowa kluczowe

PL

odporność na pełzanie; korozja; powłoki aluminiowe; powłoki ochronne; nadstop

EN

creep-resistance; corrosion; aluminium protective coatings; superalloy

• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 17, nr 1-2
• Strony: 177--180
• Opis fizyczny: Bibliogr. 15 poz., rys., tab., wykr.

Twórcy

autor

Cieśla, M.

• Department of Material Engineering and Metallurgy, Silesian University of Technology, 40 019 Katowice, ul. Krasińskiego 8, Poland,

autor

Swadźba, L.

• Department of Material Engineering and Metallurgy, Silesian University of Technology, 40 019 Katowice, ul. Krasińskiego 8, Poland

Bibliografia

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