#author("2020-12-20T10:26:19+09:00","","") *Copntents [#hce80daf] #author("2020-12-20T10:28:31+09:00","","") *Contents [#hce80daf] -[[Formation of beta-FeSi2 intermetallic compounds>#db643c07]] -[[Solidification microstructures of Fe-Si based silicides>#df375e8a]] ~ ~ ------------------ *Formation of beta-FeSi2 intermetallic compounds [#db643c07] #ref(https://t-nagase.sakura.ne.jp/pict/20151005/08-01-TTT-Cu.jpg,left,nowrap,photo) ''Figure 1''~ ''TTT Diagram of the eutectoid reaction of a-Fe2Si5 (a-Fe2Si5 -> b-FeSi2 + Si) [2].''~ #ref(https://t-nagase.sakura.ne.jp/pict/20151005/08-02-TTT-MnCu.jpg,left,nowrap,photo) ''Figure 2'' ''TTT Diagram of the eutectoid reaction of a-Fe2Si5 with 1.0 at.% Mn (a-Fe2Si5 -> b-FeSi2 + Si) [2]''~ #ref(https://t-nagase.sakura.ne.jp/pict/20151005/08-02-Periodic.jpg,left,nowrap,photo) ''Figure 3''~ ''Elements for the accelerating the eutectoid reaction of a-Fe2Si5 (a-Fe2Si5 -> b-FeSi2 + Si) [3]''~ ~ Beta-FeSi2 with high thermoelectric properties cannot be directly obtained from the thermal melt. The extremely long annealing is necesary for obtaining b-FeSi2 phase. The b-FeSi2 phase formation can be accelerated by small amount of Cu addition, especially for the eutectoid reaction of a-Fe2Si5 (a-Fe2Si5 -> b-FeSi2+ Si) [1]. We firstly constructed TTT diagram of the eutectoid reaction (a-Fe2Si5 -> b-FeSi2+ Si) for the development of Fe-Si based thermoelectric materials [2]. The eutectoid reaction of a-Fe2Si5 (a-Fe2Si5 -> b-FeSi2+ Si) can be accelerated by the small amount of Cu, Pd and Au addition, while the phase transformation rate is not affected by Ag and Pt addition [3].~ ~ REFERENCES~ [1] I. Yamauchi, A. Suganuma, T. Okamoto, I. Ohnaka: J. Mater. Sci. 32, (1997) 4603., http://dx.doi.org/10.1023/A:1004323930521~ [2] I. Yamauchi, T. Nagase, I. Ohnaka: J. of alloys and compounds, 292, 181-190 (1999)., http://dx.doi.org/10.1016/S0925-8388(99)00155-3~ [3] I. Yamauchi, T. Nagase, I. Ohnaka: J. of Mater. Sci. 37, 1429-1435 (2002)., http://dx.doi.org/10.1023/A:1014545302508~ ~ ~ ~ ---- *Solidification microstructures of Fe-Si based silicides [#df375e8a] REFERENCES~ [1] T. Nagase, I. Yamauchi, I. Ohnaka, J. of alloys and compounds, 312, 295-301 (2000)., "Effect of rapid solidification on microstructure of various Fe29.5-xSi70.5+x(0≦x≦3.7) alloys", http://dx.doi.org/10.1016/S0925-8388(00)01142-7~ [2] T. Nagase, I. Yamauchi and I. Ohnaka, J. of alloys and compounds, 316, 212-219 (2001)., "Eutectoid decomposition in rapidly solidified a-Fe2Si5-based thermoelectric alloys", http://dx.doi.org/10.1016/S0925-8388(00)01453-5~