ORIGINAL ARTICLE Development of the 90WC-8Ni-2Cr 3 C 2 cemented carbide for engineering applications Nádia Alves Nery Balbino 1 & Edmilson Otoni Correa 1 & Lívio de Carvalho Valeriano 1 Received: 30 April 2018 /Accepted: 24 July 2018 # Springer-Verlag London Ltd., part of Springer Nature 2018 Abstract In this paper, the microstructure and mechanical properties of 90WC-8Ni 2Cr 3 C 2 cemented carbide, developed by powder metallurgy, were investigated using optical and scanning electron microscopy, XRD, and hardness tester. The results showed that the addition of 2 wt% Cr 3 C 2 in the WC-Ni alloy system, using conventional adding method, was not favorable to densifi- cation. The porosity was characterized by the presence relatively large elongated pores distributed in the microstructure. As a result, there were not significant improvement of the hardness and flexural strength of the WC-8Ni-2 Cr 3 C 2 cemented carbide in comparison with WC-10Ni cemented carbides without Cr 3 C 2 addition, obtained from the literature. Fracture toughness results showed that the cemented carbide WC-8Ni-2Cr 3 C 2 presented higher fracture toughness than that of WC-Co, WC-Co-2Cr 3 C 2 , and WC-Ni alloys from literature, which may be mainly attributed to the effectiveness of Cr 3 C 2 to inhibit the excessive grain growth of the WC particles, producing a more refined and tough microstructure. Thus, despite the porosity, the mechanical properties values obtained of the developed 90WC-8Ni-2Cr 3 C 2 cemented carbide are adequate for several engineering applica- tions, where is required a good balance between hardness, wear resistance, and toughness. Keywords Powder metallurgy . WC-Ni cemented carbide . Cr 3 C 2 addition . Microstructure . Mechanical properties 1 Introduction The most used cemented carbides consist of a large amount of tungsten monocarbide particles (hard phase) agglomerated with a low-melting cobalt binder [1, 2]. However, for several appli- cations, which require a much better oxidation, corrosion, and wear resistance as well as a good balance between hardness toughness, such as petroleum pools drilling, construction, min- ing, geothermal industries, cold work dies, abrasion resistant parts, etc., WC-Ni cemented carbides has been used as an ade- quate substitute of WC-Co cemented carbides [3–8]. In the search for a better performance of tungsten cemented carbides, several studies have shown that additions of other carbides to the starting powder mixture plays an important role on the WC grain growth and binder phase strengthening during sintering and, consequently, on the mechanical properties and wear resistance improvement of these materials [9–14]. According to several works [15–20], additions of Cr 3 C 2 are often used in the WC-Co cemented carbides production to inhibit grain growth of WC particles as well as to improve corrosion resistance and mechanical properties. However, studies have showed that the interaction of cobalt metal and metallic carbides results in lung toxicity. On the other hand, the development of tungsten cemented carbides with the addition of Ni binder and Cr 3 C 2 has attracted great interest to the several industry applications. Besides their lower cost and toxicity, the combination of the Ni tough with approximately 2 wt% of Cr 3 C 2 grain inhibitor reduces the po- rosity and produces good hardness, superior corrosion resistance, and fracture toughness in comparison with WC-Co-Cr 3 C 2 [1, 12]. However, studies about the effect of Cr 3 C 2 addition on the microstructure and mechanical properties of WC-Ni cemented carbides are still very sparse. Apparently, only Kai-hua et al. [1] studied the effect of Cr 3 C 2 addition on the density and mechan- ical properties of WC-Ni cemented carbides. The authors showed that the density and mechanical properties of the WC- * Nádia Alves Nery Balbino nadiaanery@gmail.com Edmilson Otoni Correa ecotoni@unifei.edu.br Lívio de Carvalho Valeriano liviovaleriano@yahoo.com.br 1 Universidade Federal de Itajubá, Av. BPS, 1303, Pinheirinho, PO Box 50, Itajubá, Minas Gerais 37500-903, Brazil The International Journal of Advanced Manufacturing Technology https://doi.org/10.1007/s00170-018-2511-y