Effects of doping elements in β-FeSi2 prepared utilizing cast iron scrap chips

• Main Authors: Nor Hairin, Assayidatul Laila, Nanko, Makoto, Takeda, Masatoshi
• Format: Article
• Language: English; English; English
• Published: Japan Institute of Metals (JIM) 2016
• Subjects: TA401 Materials of engineering and construction
• Online Access: http://irep.iium.edu.my/56418/1/56418_Effects%20of%20doping%20elements%20in%20%CE%B2-FeSi2%20prepared%20utilizing%20cast%20iron%20scrap%20chips.pdf; http://irep.iium.edu.my/56418/8/56418_Effects%20of%20doping%20elements_SCOPUS.pdf; http://irep.iium.edu.my/56418/14/56418_Effects%20of%20doping%20elements%20in%20%CE%B2-FeSi2_WoS.pdf; http://irep.iium.edu.my/56418/; https://www.jim.or.jp/journal/e/57/03/445.html

In this work, the thermoelectric properties of p- and n-type β-FeSi2, prepared utilizing cast iron scrap chips, have been characterized by measuring the Seebeck coefficient, electrical conductivity and thermal conductivity at temperatures ranging from room temperatures to 800°C. In a previous study, the upgrade recycling of cast iron scrap chips into β-FeSi2 thermoelectric materials was proposed as an eco-friendly and costeffective production process. By doping with different substitution concentrations of Co, Mn and Al, the conduction type and properties of β-FeSi2 can be modified and improved using cast iron scrap chips as a starting material. The effects of the doping elements are discussed for preparing β-FeSi2 utilizing cast iron scrap chips. Cast iron scrap chips could be preferable as a starting material to replace pure Fe for n- and ptype β-FeSi2 thermoelectric materials. An optimum composition for n-type β-FeSi2 0.94C.I.-0.06Co-1.86Si shows that the largest ZT value of 0.22 occurs at 700°C, whereas for p-type β-FeSi2 0.92C.I.-0.08Mn-1.86Si, the largest ZT value of 0.17 occurs at 800°C.