Gülşah AKTAŞ ÇELİK, Şeyda POLAT, Şaban Hakan ATAPEK, Sinan FİDAN

SiMo sünek dökme demirin katı partikül erozyonu

SiMo sünek dökme demir yüksek sıcaklıklarda ekzoz manifold malzemesi olarak geliştirilmiştir. Kimyasal kompozisyonunda bulunan Si ve Mo elementleri yüksek sıcaklık oksidasyon direnci ve yüksek sıcaklık mukavemeti sağlamaktadır. Çalışma koşullarında yüksek sıcalıktaki korozif ekzoz gazı ekzoz manifoldundan geçer ve manifold yüzeyinde erozyona neden olabilir. Bu çalışmada, SiMo dökme demirin katı partikül erozyon davranışının aluminyum oksit partikülleri ile 30°, 45°, 60° ve 90° çarpma açıları kullanılarak incelenmesi hedeflenmiştir. Yüzeyde meydana gelen bozunmalar tarama elektron mikroskopu kullanılarak incelenmiştir. Erozyon oranı 45° çarpma açısına kadar artış gösterirken, malzeme kaybı mekanizmasındaki değişiklik nedeniyle daha bu oran yüksek açılarda azalmıştır. Düşük açılarda pulluklama etkin mekanizma iken yüksek açılarda yüzeyde deformasyon sertleşmesi meydana gelmektedir.

Anahtar Kelimeler:

SiMo sünek dökme demir, katı partikül erozyonu

Solid particle erosion behavior of SiMo ductile cast iron

SiMo ductile cast iron has been developed to be used at high temperatures as exhaust manifold material. Si and Mo contents in its chemical composition provide high temperature oxidation resistance and high temperature strength. During service, hot corrosive exhaust gas flows through the exhaust manifold and may cause erosion of the manifold surfaces. Thus, in this study, it was aimed to evaluate the performance of SiMo cast iron under severe solid particle erosion conditions, against aluminum oxide particles at 30°, 45°, 60° and 90° impingement angles. Surface degradation of tested alloys were characterized using scanning electron microscope. It was observed that erosion rate increased with increasing impingement angle up to 45°, then decreased as the angle increased, since the mechanism of material removal changed. While ploughing occurred at lower angles, work hardening took place on the worn surface at higher angles.

Keywords:

SiMo ductile cast iron solid particle erosion, characterization,

PDF

___

[1] P. Matteis, G. Scavino, A. Castello, D. Firrao, “High-cycle fatigue resistance of Si-Mo ductile cast iron as affected by Temperature and strain rate”, Metall and Materi Trans A, vol.46A, p. 4086-4094, 2015.
[2] L. M. Åberg, C. Hartung, “Solidification of SiMo nodular cast iron for high temperature applications”, Trans Indian Inst Met vol. 65, no.6, p.633–636, 2012.
[3] M. Ekström, S.Jonsson,” High-temperature mechanical-and fatigue properties of cast alloys Intended for use in exhaust manifolds”, Mater. Sci. Eng., A, vol 616, p.78–87, 2014.
[4] P. Matteis, G. Scavino, A. Castello, D. Firrao, High temperature fatigue properties of a Si-Mo ductile cast iron, Procedia Mater. Sci., vol. 3, p. 2154-2159, 2014
[5] D. Li, Discussion of “Microstructure and hot oxidation resistance of SiMo ductile cast irons containing Si-Mo-Al”, Metall and Materi Trans B, vol. 49B, p. 858-859, 2018.
[6] M. Ekström, P. Szakalos, S. Jonsson, Influence of Cr and Ni on high-temperature corrosion behavior of ferritic ductile cast iron in air and exhaust gases, Oxid. Met. vol. 80, p. 455–466, 2013.[7] A. A. Partoaa, M. Abdolzadeh, M. Rezaeizadeh, “Effect of fin attachment on thermal stress reduction of exhaust manifold of an off road diesel engine”, J. Cent. South Univ. vol. 24 p. 546−559, 2017.
[8] L. C. Chang, I. C. Hsui, L. H. Chen, T. S. Lui, “A study on particle erosion behavior of ductile irons”, Scripta Materialia, vol. 52, p. 609-613, 2005.
[9] M. A. Islam, Z.N. Farhat, “Effect of impact angle and velocity on erosion of API X42 pipeline steel under high abrasive feed rate”, Wear, vol. 311, p. 180-190, 2014. [10] M. Divakar, V. K. Agarwal, S. N. Singh, “Effect of the material surface hardness on the erosion of AISI316”, Wear, vol. 259, p. 110-117, 2005.
[11] K. Yıldızlı, M. B. Karamış, F. Nair, “Erosion mechanisms of nodular and gray cast irons at different impact angles”, Wear, vol. 261, p. 622-633, 2006.
[12] L. C. Chang, I. C. Hsui, L. H. Chen, S. T. Lui, “Influence of graphite nodules on the particle erosion of spheroidal graphite cast irons”, Wear, vol 257, p. 1125-1132, 2004.
[13] J. R. Laguna-Camacho, A. Marquina-Cháves, J. V. Méndez-Méndez, M. Vite-Torres, E. A. Gallardo-Hernández, “Solid particle erosion of AISI 304, 316 and 320 stainless steels”, Wear, vol. 301, p. 398-405, 2013.
[14] G. Sundararajan, M. Roy, “Solid particle erosion behavior of metallic materials at room and elevated temperatures”, Tribol. Int. vol. 3, no. 5, p. 339-359, 1997.
[15] Ş. H. Atapek, S. Fidan, “Solid particle erosion of cast alloys used in the mining industry”, Int. J. Miner., Metall. Mater, vol. 22, no. 12, p. 1283-1292, 2015.