1992 Fiscal Year Final Research Report Summary
Analysis of the Liquid State Fabrication Process of High Alloy Cast Iron-Ceramic Fiber Composites
| Project/Area Number |
03650557
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
金属加工(含鋳造)
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| Research Institution | Kyushu University |
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Principal Investigator |
OGI Keisaku Kyushu University,Faculty of Engineering,Dpt.of Materials Science and Engineering,Professor, 工学部, 教授 (40038005)
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| Co-Investigator(Kenkyū-buntansha) |
ONO Yukinori Kyushu University,Faculty of Engineering,Dpt.of Materials Science and Engineerin, 工学部, 助手 (10204257)
MORI Nobuyuki Kyushu University,Faculty of Engineering,Dpt.of Materials Science and Engineerin, 工学部, 助手 (20108666)
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| Project Period (FY) |
1991 – 1992
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| Keywords | Composites / Casting / High Alloy Cast Iron / Ceramics / Infiltration Process / Wettability / Interface Reaction / Abrasion |
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| Research Abstract |
The wetting angles of molten cast irons containing 0-25%Cr,15%Cr-5%V or 15%Cr-0.5%Ti were measured on smooth transparent Al_2O_3 substrates by the sessile drop method. The wetting angles of these molten alloys were among 105ﾟand 125ﾟat the melting points,and they decreased with the increase in Ti or V content. The higher surface roughness and porosity of substrates decreased the wettability.The apparent contact angles(theta)of these substrates were evaluated by Cassie's equation. Further,the wettability and the interface reaction of the above cast iron melts on sintered ZrO_2,SIA LON,Si_3N_4,SiC and WC were also clarified.
The infiltration process of molten metal into fibrous perform,heated to the same temperature as the molten metal,was simulated by using Al-5.5%Cu alloy melt.The average permeability(Ka)and the average fiber radius(Rfa)were obtained experimentally from the pressure profile. The perform was assumed to be composed of 20 different permeability(K)and hydraulic mean radius(Rh)regions,and the simulation of fluid flow in the perform revealed that the pressure gradually increased as the infiltration proceeded to smaller Rh regions.
The squeeze casting of various molten alloy cast irons into pre-heated Al_2O_3 short fiber perform was conducted.In this case,the solidification of molten metal made the Rh smaller,and caused many small pores especially in 15%Cr-5%V cast iron.The solidification processes of these alloys were as follows. After the crystallization of primary austenite(gamma) on Al_2O_3 short fibers,gamma-VC,gamma-(CrFe)_7C_3, or gamma-(FeCr)_3C eutectic solidified according to the composition of cast iron.The abrasion wear registance of Fe-2.7%C-1.5%Cr-1%Mo-0.4%Si-0.8%Mn cast iron with about 8vol.%Al_2O_3 short fibers was investigated by Suga-type wear testing machine.The wear rate of the cast iron with Al_2O_3 fibers decreased under 1/2 of that of the fiber-free cast iron of the same chemical composition.
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