Abstract: An iron-based sintered alloy of the present invention is an iron-based sintered alloy, which is completed by sintering a powder compact made by press forming a raw material powder composed of Fe mainly, and is such that: when the entirety is taken as 100% by mass, carbon is 0.1-1.0% by mass; Mn is 0.01-1.5% by mass; the sum of the Mn and Si is 0.02-3.5% by mass; and the major balance is Fe. It was found out that, by means of an adequate amount of Mn and Si, iron-based sintered alloys are strengthened and additionally a good dimensional stability is demonstrated. As a result, it is possible to suppress or obsolete the employment of Cu or Ni, which has been believed to be essential virtually, the recyclability of iron-based sintered alloys can be enhanced, and further their cost reduction can be intended.

Abstract: A process for producing ferrous sintered alloy according to the present invention is characterized in that it is equipped with: a compaction step of pressure compacting a raw-material powder in which an Fe-system powder is mixed with a reinforcement powder, thereby turning the raw-material powder into a powder compact; and a sintering step of heating this powder compact in an oxidation preventive atmosphere, thereby sintering the powder compact; and said reinforcement powder is an Fe—Mn—Si—C powder comprising an Fe alloy or an Fe compound that includes: Mn in an amount of from 58 to 70%; Si in an amount making a compositional ratio of the Mn with respect to the Si (i.e., Mn/Si) that is from 3.3 to 4.6; and C in an amount of from 1.5 to 3%; when the entirety is taken as 100% by mass. This Fe—Mn—Si—C powder is procurable inexpensively relatively; besides, ferrous sintered alloys, which are obtained using that, are better in terms of various characteristics than are conventional ferrous sintered alloys.

Abstract: An iron-based sintered alloy of the present invention is an iron-based sintered alloy, which is completed by sintering a powder compact made by press forming a raw material powder composed of Fe mainly, and is such that: when the entirety is taken as 100% by mass, carbon is 0.1-1.0% by mass; Mn is 0.01-1.5% by mass; the sum of the Mn and Si is 0.02-3.5% by mass; and the major balance is Fe. It was found out that, by means of an adequate amount of Mn and Si, iron-based sintered alloys are strengthened and additionally a good dimensional stability is demonstrated. As a result, it is possible to suppress or obsolete the employment of Cu or Ni, which has been believed to be essential virtually, the recyclability of iron-based sintered alloys can be enhanced, and further their cost reduction can be intended.

Abstract: A pressurizing forming process includes the steps of applying a higher fatty acid-based lubricant on a surface of a metallic workpiece and/or a forming surface of a forming tool, and forming, wherein a lubricating film including metallic soap is formed on a pressurized-and-contacted interface, at which the surface of the metallic workpiece and the surface of the forming tool are pressed against and are brought into contact with each other, in forming the metallic workpiece by pressurizing with the forming tool. The metallic workpiece and/or the forming tool can be heated prior to or in the forming step.

Abstract: An iron-based sintered alloy of the present invention is an iron-based sintered alloy, which is completed by sintering a powder compact made by press forming a raw material powder composed of Fe mainly, and is such that: when the entirety is taken as 100% by mass, carbon is 0.1-1.0% by mass; Mn is 0.01-1.5% by mass; the sum of the Mn and Si is 0.02-3.5% by mass; and the major balance is Fe. It was found out that, by means of an adequate amount of Mn and Si, iron-based sintered alloys are strengthened and additionally a good dimensional stability is demonstrated. As a result, it is possible to suppress or obsolete the employment of Cu or Ni, which has been believed to be essential virtually, the recyclability of iron-based sintered alloys can be enhanced, and further their cost reduction can be intended.

Abstract: This invention provides a method of forming a powder compact which can produce a high density compact under a high pressure and at the same time can reduce pressure for ejecting the compact from a die. This method comprises the application step of applying a higher fatty acid lubricant to an inner surface of a heated die, and the compaction step of filling metal powder into the die and compacting the metal powder under such a pressure as to force the higher fatty acid lubricant to be chemically bonded with the metal powder and form a metallic soap coating. Since the metallic soap coating is formed between the die and a compact, friction force between the die and the compact is decreased and ejecting pressure can be remarkably decreased despite of compaction with high pressure. Besides, a high density compact can be obtained owing to the compaction with high pressure.

Abstract: A pressurizing forming process includes the steps of applying a higher fatty acid-based lubricant on a surface of a metallic workpiece and/or a forming surface of a forming tool, and forming, wherein a lubricating film including metallic soap is formed on a pressurized-and-contacted interface, at which the surface of the metallic workpiece and the surface of the forming tool are pressed against and are brought into contact with each other, in forming the metallic workpiece by pressurizing with the forming tool. The metallic workpiece and/or the forming tool can be heated prior to or in the forming step.

Abstract: This invention provides a method of forming a powder compact which can produce a high density compact under a high pressure and at the same time can reduce pressure for ejecting the compact from a die.

Abstract: A method and apparatus for filling a cavity with powder wherein a pipe having holes for discharging gas is disposed in a powder box and gas is discharged into the powder in the powder box as the powder enters the cavity so that particles of the powder are movable relative to each other. Due to the gas discharge, the powder can enter the cavity smoothly without whirling up in the cavity and settling unevenly, so that a filling time period is shortened and a particle size distribution in the cavity is uniform.