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Research paper−290−Synthesiology - English edition Vol.3 No.4 pp.290-298 (Mar. 2011) cutting, and its use in molds will facilitate forming processes in middle to high temperature ranges. It is anticipated that such applications will reduce energy consumption during the forming process, contributing to the goal of achieving a low carbon society. It is essential to provide heat resistance to the binder phase of the cemented carbide for these applications. In this paper, we describe the development at AIST of a new cemented carbide using an iron aluminide intermetallic compound[1] as the binder phase. We present an evaluation of its mechanical characteristics and a property evaluation required for its industrial use and applicability to peripheral technologies. This research was carried out by a group consisting of several researchers with different specialties. 2 Objectives and goals of the researchThe effective use of intermetallic compounds to improve the heat resistance of hard composites is well documented, with reports of comprehensive studies by universities, private companies, and national institutes in the project of the Ministry of Economics, Trade and Industry since 1990. As a consequence, intermetallic iron-based materials were considered. Intermetallic compounds comprise an ordered phase of different metal elements, and are known to exhibit properties somewhere between those of ceramics and metals. Particularly, the aluminum-based intermetallic compound called “aluminide” shows reverse temperature dependency of the material strength, and offered promise as a metal-based material for use in the middle-high temperature range. Through collaboration with private companies, AIST has previously studied the synthesis of aluminide 1 Background of research Cemented carbide, which is widely used in molds and cutting tools, is a composite material with high strength and hardness. It is fabricated by sintering hard tungsten carbide with cobalt. It is an essential material for precision machining technologies, which are used by many Japanese advanced industries, for example, automobile industry and information appliance industry. Cemented carbides have a long history. Japanese exports of carbide tools are increasing annually, with an increase of over 350 billion yen reported in 2007 (statistics according to the Japan Cemented Carbide Tool Manufacturers’ Association). However, with increasing global industrialization, concern over the long-term stable supply of tungsten and cobalt is growing. Particularly, the rare metal cobalt has been subject to radical price fluctuation. Furthermore, the development of a new metallic binder phase is highly desirable from the environmental perspective. For these reasons, AIST started directing efforts toward the development of a new composite material of a metal and ceramic with high strength and hardness. An ideal metal for use in these composites is iron, which is an abundant resource with a stable price. However, the use of iron presents significant challenges owing to its high reactivity with carbides (e.g., tungsten carbide) and its propensity to rust. Therefore, cemented carbides with iron as the binder phase have not been previously used practically. However, there is a demand for cemented carbide for use in high-temperature applications in the machining industry. For example, the use of cemented carbide in cutting tools will facilitate both high-speed cutting and unlubricated - A high-performance hard material which used intermetallic compound for binder phase-Keizo Kobayashi*, Kimihiro Ozaki, Akihiro Matsumoto and Hiroyuki NakayamaMaterials Research Institute for Sustainable Development, AIST 2266-98 Anagahora, Shimo-Shidami, Moriyama-ku, Nagoya 463-8560, Japan *E-mail : Original manuscript received July 30, 2010, Revisions received August 25, 2010, Accepted August 30, 2010 Hard materials made of ceramics combined with metals are used for dies and cutting tools that support high precision processing technology in Japan. Hard materials, however, need a large amount of rare metals that are scarce as resources as component and hence developing new materials with less dependence on rare metals has been expected. We developed a new hard material with Fe-Al intermetallic compound as a binder. This material was synthesized by a process combining casting and powder metallurgy and exhibited high hardness and high strength simultaneously. This paper introduces an approach to “Type2 Basic Research” in order to apply the developed material to industrial use, and a method of efficient research and development through the collaboration of researchers of different specialized fields. New material development by the integration of cast technology and powder metallurgy technologyKeywords : Cemented carbide, FeAl, mechanical alloying, pulsed current sintering, die, cutting tool[Translation from Synthesiology, Vol.3, No.4, p.301-308 (2010)]

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