Wear 258 (2005) 189–193 High temperature abrasive wear behavior of an as-cast ductile iron Ozgur Celik, Hayrettin Ahlatci, E. Sabri Kayali, Huseyin Cimenoglu ∗ MetallurgyandMaterialsEngineeringDepartment,IstanbulTechnicalUniversity,34469Maslak,Istanbul,Turkey Received 22 December 2003 Available online 13 October 2004 Abstract In this study, high temperature abrasive wear behavior of a GGG 40 quality as-cast ductile iron was examined. Wear tests were performed under a compression stress of 5.7 N/mm 2 , by rubbing the samples (pins) on Al 2 O 3 abrasive grains at various temperatures in between 25 and 600 ◦ C. The examined ductile iron exhibited the highest resistance to abrasion at temperature range between 50 and 100 ◦ C. Tensile tests carried out at 100 ◦ C revealed occurrence of serrated flow on the stress–strain curve, which is the indication of strain aging. © 2004 Elsevier B.V. All rights reserved. Keywords: Abrasion; Ductile iron; High temperature; Strain aging; Tensile test; Wear 1. Introduction Since abrasive wear is one of the common failure mech- anisms of engineering components, it has become an impor- tant subject in tribology and materials science. Ductile irons, which have been evolving over the past few decades, are of considerable current interest because they can offer a better combination of strength and toughness. Application of duc- tile irons in components like gears, pinions, crankshafts and similar parts requiring improved wear resistance, induces in- terests in their wear behavior. As is well known, the wear performance of a material can be influenced by many factors. Among these factors, the microstructure and the nature of the material are extremely important. The matrix structure of ductile iron can be fer- ritic, pearlitic, bainitic or martensitic depending on the com- position, cooling rate and heat treatment conditions [1–4]. The ferritic ductile irons exhibit best ductility. They can be used usually at elevated temperatures because ferrite retains its stability up to 600 ◦ C [5]. However, there is no literature related with high temperature wear performance of ferritic ductile irons. The aim of the present study was to examine ∗ Corresponding author. Tel.: +90 212 285 6834; fax: +90 212 285 3427. E-mailaddress: cimenogluh@itu.edu.tr (H. Cimenoglu). the abrasive wear features of a ferritic ductile iron at elevated temperatures [6,7]. 2. Experimental procedure A commercial GGG 40 quality (3.7 C–2.9 Si–0.16 Mn–0.04 Mg–0.18 Cu–0.01 N) as-cast ductile iron was used in this study. Metallographic samples were prepared in the se- quence of grinding, polishing and etching (with 3% Nital) for microscopic examinations by a Nikon Epiphot 200 type light optical microscope. The volume fractions of the microstruc- tural constituents were quantified by using a Leica DMLM optical microscope in conjunction with a computer having Q Win software program. Hardness measurements were per- formed on the metallographic samples by a Wolpert hardness tester under indention load of 20 kg with a diamond pyramid indenter. The tensile properties of the as-cast ductile iron were de- termined by utilising round-type specimens having 25 mm gauge length and 5mm gauge diameter. Tensile tests were conducted on an Instron 1185 Universal testing machine at various temperatures (25–600 ◦ C) with a constant strain rate of 3 × 10 -4 s -1 . The samples were held at the temperature for 15 min before testing. Two samples were tested at each temperature. After the tensile tests, fracture surfaces of the 0043-1648/$ – see front matter © 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.wear.2004.09.004