Wyniki wyszukiwania - BazTech

1

The influence of bond-coat thickness on the temperature distribution and stress level in thermal barrier coatings system

Jasik Anna

Ochrona przed Korozją

|

2019

|

nr 2

41--45

EN

The paper presents the results of numerical calculation of the temperature distribution and thermal stresses in model of two layered thermal barriers coatings of DCL type deposited on the superalloy coupons with NiCrAlY bond-coat. The variable parameter was the thickness of bond-coat layers. In all cases it was assumed that the bond-coat would be the NiCrAlY type coat obtained by plasma spraying, just as the outer insulating layer. The thickness of the bond-coat layer is 100 μm to 300 μm. As the substrate material, the In 625 nickel superalloy was adopted. The insulation layer of TBC systems was built from outer sublayer based on La2Zr2O7 (LZO) ceramic and internal layer was built from conventional 8YSZ. A total thickness of insulation layer was assumed as 300 μm. Presented analysis showed that the overall thickness of bond-coat has important influence on the temperature distribution as well as the thermal stresses. The maximum temperature differences between extreme thickness value was calculated on the level of 50°C.

PL

W opracowaniu przedstawiono wyniki obliczeń numerycznych rozkładu temperatury i naprężeń termicznych w powłokowych barierach cieplnych typu DCL naniesionych na elemencie nadstopu z warstwą wiążącą typu NiCrAlY. Zmiennym parametrem była grubość warstw wiążących. We wszystkich przypadkach założono, że powłoka wiążąca była powłoką typu NiCrAlY otrzymaną przez natryskiwanie plazmowe, podobnie jak zewnętrzna warstwa izolacyjna. Grubość warstwy powłoki wiążącej wynosi od 100 μm do 300 μm. Jako materiał podłoża przyjęto super -stop niklu In 625. Warstwa izolacyjna systemów TBC została zbudowana z zewnętrznej warstwy nośnej na bazie ceramicznej La2Zr2O7 (LZO), natomiast wewnętrzna warstwa została zbudowana z konwencjonalnego proszku 8YSZ. Całkowitą grubość warstwy izolacyjnej przyjęto jako 300 μm. Przedstawiona analiza wykazała, że całkowita grubość warstwy wiążącej ma istotny wpływ na rozkład temperatury, jak również na naprężenia termiczne. Maksymalne różnice temperatur pomiędzy ekstremalną wartością grubości obliczono na poziomie 50 ° C.

2

Thermal barrier coatings : characteristics of microstructure and properties, generation and directions of development of bond

Moskal G.

Journal of Achievements in Materials and Manufacturing Engineering

|

2009

|

Vol. 37, nr 2

323-331

EN

Purpose: The goal of the paper is to present the review of characterisation of microstructure, properties as well as technology of receiving the heat resistance layers used as bond coats in thermal barrier coatings. Design/methodology/approach: General structure characterisation of the final influence of individual TBC`s sublayers was described. Especially the detailed characterisation of bond coats such as MeCrAlY and aluminides diffusion coatings was showed (used for EB-PVD obtained TBC`s). Findings: The influence of modification of chemical composition was described on microstructure and property of bond coats as well. It defines reactive elements such as Hf and the noble metals - Pt influence on increasing of heat resistance of bond coats, and, as a consequence, the growth of durability of coating thermal barriers. Different methods of modification of basic layers, for example the additional aluminizing process of MCrAlY coating was described as well. Practical implications: Additionally, the other types of bond coats were characterised, typically used for energy conversion systems and in case of Diesel engines and especially bond coats for titanium and titanium aluminides alloys. Originality/value: In the last part of the paper, new concepts such as „smart coatings” and diffusion barriers were shown.

3

Thermal barrier coatings: Part 1 – characteristics of microstructure and properties, generation and directions of development of bond

Moskal G.

Archives of Materials Science

|

2007

|

Vol. 28, nr 1-4

100-112

EN

In this article the review characterization of microstructure, property as well as technology of receiving the heat resistance layers used as bond coats in thermal barrier coatings was presented. General structure characterization end influence of individual TBC`s sublayers was described. Especially the detailed characterization of bond coats such as MeCrAlY and aluminides diffusion coatings was showed (used for EB-PVD obtained TBC`s). The influence of modification of chemical composition was described on microstructure and property of bond coats as well. It define of reactive elements such as Hf and the metals noble - Pt influence on increasing of heat resistance of bond coats, and in consequence the growth of durability of coating thermal barriers. Different methods of modification of basic layers, for example the additional aluminizing process of MCrAlY coating was described as well. Additionally others types of bond coats was characterized typically used in energy conversion systems and in the case of Diesel engines and especially bond coats for titanium and titanium aluminides alloys. In the last part of article new conceptions such as "smart coatings" and diffusion barriers was shown.