A new concept for stainless steels ranking upon the resistance to cavitation erosion

International Conference on Applied Sciences 2016

Bordeasu, I.^1 ; Popoviciu, M.O.^2 ; Salcianu, L.C.^1 ; Ghera, C.^1 ; Micu, L.M.^3 ; Badarau, R.^1 ; Iosif, A.^4 ; Pirvulescu, L.D.^5 ; Podoleanu, C.E.^4

Politehnica University of Timisoara, Faculty of Mechanical Engineering, Mihai Viteazul Street, Nr. 1, Timisoara

300222, Romania^1

Academy of Romanian Scientists, Mihai Viteazul Street, Nr. 1, Timisoara

300222, Romania^2

Universitatea de Stiinte Agric. Si Med. Veterinara A Banatului Regele Mihai i Romaniei Din Timisoara, Calea Aradului nr.119, Timioara

300645, Romania^3

Politehnica University of Timisoara, Faculty of Civil Engineering, Traian Lalescu Street, Nr. 2, Timisoara

300223, Romania^4

Casa Auto Timisoara Merceds-benz, Romania^5

关键词: Cavitation erosion resistance;    Cavitation resistance;    Characteristic curve;    Exponential equations;    Field measurement;    Laboratory test;    Scale and shape parameters;    Scale parameter;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/163/1/012002/pdf
DOI  :  10.1088/1757-899X/163/1/012002

来源: IOP

【 摘 要 】

In present, the ranking of materials as their resistance to cavitation erosion is obtained by using laboratory tests finalized with the characteristic curves mean depth erosion against time MDE(t) and mean depth erosion rate against time MDER(t). In some previous papers, Bordeasu and co-workers give procedures to establish exponential equation representing the curves, with minimum scatter of the experimental obtained results. For a given material, both exponential equations MDE(t) and MDER(t) have the same values for the parameters of scale and for the shape one. For the ranking of materials is sometimes important to establish single figure. Till now in Timisoara Polytechnic University Cavitation Laboratory were used three such numbers: the stable value of the curve MDER(t), the resistance to cavitation erosion (Rcav≡ 1/MDERstable) and the normalized cavitation resistance Rnswhich is the rate between vs= MDERstablefor the analyzed material and vse= MDERsethe mean depth erosion rate for the steel OH12NDL (Rns = vs/vse ). OH12NDL is a material used for manufacturing the blades of numerous Kaplan turbines in Romania for which both cavitation erosion laboratory tests and field measurements of cavitation erosions are available. In the present paper we recommend a new method for ranking the materials upon cavitation erosion resistance. This method uses the scale and shape parameters of the exponential equations which represents the characteristic cavitation erosion curves. Till now the method was applied only for stainless steels. The experimental results show that the scale parameter represents an excellent method for ranking the stainless steels. In the future this kind of ranking will be tested also for other materials especially for bronzes used for manufacturing ship propellers.