Iron-based sintered body, for light metal alloy, comprises carbon, copper, and iron, and has structure containing pores and free copper phases dispersed in matrix

摘要

An iron-based sintered body comprises a composition comprising (mass%) carbon (0.5-2.5), copper (5-40), and a balance of iron, and a structure containing pores and free copper phases dispersed in a matrix. An average thermal expansion coefficient from room temperature to 200[deg]C is =13.5X10-6 per [deg]C and a surface roughness (Rz) of 10-100, and has excellent enveloped casting property in a light metal alloy. An independent claim is also included for a method for producing the above iron-based sintered body used for being enveloped in a light metal alloy by casting, by preparing a mixed powder by blending an iron-based powder, copper powder, graphite powder and lubricant powder; filling the mixed powder into a mold; forming a green compact by press-molding; and forming a sintered body by sintering the green compact, where a pure iron is used as the iron-based powder, and sintering condition of the sintering is controlled, so that the average thermal expansion coefficient of the sintered body is =13.5X10-6 per [deg]C from room temperature to 200[deg]C; and the Rz is adjusted to 10-100 Microm.