TMMOB Metalurji ve Malzeme Mühendisleri Odas ı E ğ itim Merkezi Bildiriler Kitab ı 315 19. Uluslararas ı Metalurji ve Malzeme Kongresi | IMMC 2018 Efects of Mo and B Additions on Induction Hardening of Fe-C-Ni-Cu Metal Matrix Composites Produced by Warm Compaction Method Tarık Gün¹, Mehmet Şimşir², Bahadır Karaca¹, Fatih Özaydın¹ ¹ESTAŞ Eksantrik San. ve Tic. A.Ş. Sivas-Turkey, ²Cumhuriyet University, Engineering Faculty, Department of Metallurgy and Materials Eng.. Sivas-Turkey Abstract In this study, effects of addition of Mo (0.6, 1.2 and 1.8 wt%) and B (0.2, 0.6 and 1.0 wt%) elements into Fe base metal matrix composites (Fe- 0.8 C- 2.0 Cu- 3.0 Ni (wt%)) were investigated. The composite materials were produced by applying warm compaction and free sintering methods sequentially. Green composites were produced under pressure of 650 MPa at 160 °C. Then, the green products have been sintered at 1050 °C and 60 min sintering time in controlled Argon (Ar) gas atmosphere. After production of the composite samples, induction hardening heat treatment was applied to composite samples. The microstructures of the samples have been examined before and after induction hardening under optical microscopy. Surface hardness and density of the composite samples were measured. The results have showed that the addition of Mo and B elements increases surface hardness of the Fe based composite material. The highest surface hardness has been obtained in the case of Mo=1.8 and B=1.0 composition. 1. Introduction The application of powder metallurgy (PM) manufacturing processes is growing and often it replaces traditional metal- forming operations because of a near-net shape forming capability, a more efficient material utilization, a relatively low energy consumption and capital cost [1]. In particular, the demand for PM steel components is significantly increasing and different PM steels have found applications, mainly in the automotive industry for engine and transmission systems [1]. Therefore, some P/M structural parts with high sintered density as well as high wear resistance have been found wide applications in the automotive systems, such as cam lobes, gears and valve seats, etc., mainly required for good wear resistance [2]. The surface hardening was usually carried out for these components to obtain a harder layer on surfaces and tough core in the center, which exhibit both high wear resistance and strength. In the past few years, surface hardening processes such as gas nitriding [3] plasma nitriding, glow-discharge treatment [4], nitriding and nitrocarburizing [5], as well as surface carburizing [6] treatments have been widely used for surface hardening treatments of P/M parts. Solid carburization, as a traditional carburization method, has a lot of shortages such as poor working condition, long heating duration and low productivity. Then it has been replaced by gas carburization, vacuum carburization, ion carburization and fluid carburization. However, solid carburization can produce parts with simple equipment’s and low cost. The density of warm compaction material, Fe–4Ni–1.5Cu– 0.5Mo, could be higher than 7.25 g/cm 3 [7]. Company of Hoeganaes AB had made iron-based materials with strength of 1299 MPa through warm compaction with single sintering [8]. Effect of warm compaction on the property of Fe–Ni–Cu–Mo–C was studied in literature. PM materials of high density, strength and toughness made through warm compaction or die wall lubrication were often reported [9]. In order to improve the mechanical properties, surface compaction methods such as shot peening, deep rolling, laser shock compression as well as different heat treatment processes are used. The purpose of the mentioned procedure is to increase the strength and the wear resistance as well as to achieve a more favorable structure for improved strength carburizing [10]. The aim of this study is to produce Fe-based (Fe-0.8C- 2.0Cu-3.0Ni-XMo-YB (%)) metal matrix composite by warm compacting method for gear production. The effects of Mo (%0.6-1.2-1.8) and B (%0.2-0.6-1.0) additions were investigated on the hardness, the density and microstructure properties in induction hardening.