Abstract: An iron-based powder composition is provided that is greatly flowable and compactible and less dependent on temperature with respect to flowability and compactibility at room temperature or during warming. The iron-based powder composition includes an iron-based powder, a lubricant melted and fixed to the iron-based powder, an alloying powder bonded to the iron-based powder with the aid of the lubricant, and a free lubricant. One or more constituent members are coated with an organosiloxane layer in a coating ratio of greater than about 80%. The organosiloxane has phenyl groups as a functional group. The lubricant melted and fixed to the iron-based powder is a composite melt composed of a calcium soap and a lithium soap, or a composite melt composed of a calcium soap and an amide lubricant. The free lubricant is a mixed powder composed of an amide lubricant and a methyl polymethacrylate powder, or a lithium soap powder. A process for producing the iron-based powder composition is also provided.

Abstract: An iron-based mixed powder for use in powder metallurgy has an apparent density of at least about 3.1 Mg/m3, is excellent in die filling property and compressibility and without segregation, and includes an iron-based powder to which alloying powder is adhered at the surface by binder and free lubricant. The iron-based powder includes an atomized iron powder, or a mixed powder of an atomized iron powder and a reduced iron powder.

Abstract: An sintered iron-based powder metal body with outstandingly lower re-compacting load and having a high density and a method of manufacturing an iron-based sintered component with fewer pores of a sharp shape and having high strength and high density, the method comprising mixing,

Abstract: A Mo source powder is added to and mixed with an iron-based powder containing 1.0% by mass or less of prealloyed Mn to yield a powder mixture containing 0.2 to 10.0% by mass of Mo, the resulting powder mixture is subjected to heat treatment in a reducing atmosphere to thereby yield an alloyed steel powder containing Mo as a powder partially diffused and bonded to a surface of the iron-based powder particles. The prepared alloyed steel powder for powder metallurgy has satisfactory compactability. The use of this alloyed steel powder can produce a sintered powder metal body (an intermediate material after compaction and preliminary sintering in re-compaction of sintered powder materials process) for highly strong sintered member.

Abstract: An iron-based mixed powder for use in powder metallurgy and excellent in die filling property and compressibility and without segregation, includes an iron-based powder in which alloying powder(s) is adhered to the surface by a binder and, further, a free lubricant. The iron-based powder includes a mixed iron powder of atomized iron powder and reduced iron powder.

Abstract: A process for producing a high-density iron-based green compact is provided that can form a green compact with a high density. Also provided is a process for producing a sintered compact from the green compact. A specified combination lubricant is applied to the surface of a die for compacting by electrical charging, wherein the combination lubricant includes a first lubricant having a melting point that is higher than a preset compacting temperature, and a second lubricant having a melting point that is lower than a compacting temperature. A heated iron-based powder mixture is filled into the die, followed by compacting, whereby a green compact is formed. The green compact can be sintered to provide a sintered compact.

Abstract: A manufacturing method for high-density iron-based powder compacts is disclosed. The temperature of the die is adjusted at ordinary temperature or at a predetermined temperature by preheating. A lubricant for die lubrication prepared by mixing at least two different lubricants having melting points higher than a predetermined temperature of the compaction pressure is sprayed at the upper part of the die and is introduced into the die and adhered by electrification to the surface of the die. The resulting die is filled with an iron-based mixed powder including a lubricant and molding is performed at ordinary temperature or at a temperature raised by heating.

Abstract: The present invention intends to provide an iron-based powder composition for powder metallurgy having excellent flowability at room temperature and a warm compaction temperature, having improved compactibility enabling lowering ejection force in compaction, to provide a process for producing the iron-based powder composition, and to provide a process for producing a compact of a high density from the iron-based powder composition. The iron-based powder composition comprises an iron-based powder, a lubricant, and an alloying powder, and at least one of the iron-based powder, the lubricant, and the alloying powder is coated with at least one surface treatment agent selected from the group of surface treatment agents of organoalkoxysilanes, organosilazanes, titanate coupling agents, fluorine-containing silicon silane coupling agents.

Abstract: The object of the present invention is to provide an iron based blended powder for powder metallurgy that can provide a reformable sintered article that has a good sliding property with less variation in the property and a good impact resistance. More specifically, the iron based blended powder for powder metallurgy is formed by blending an atomized alloy iron powder with 0.01% to 1.0% of one or more types of compound powder containing B in terms of B, 1 to 10% of Ni powder, 1 to 6% of Cu powder, 1.3 to 3.0% of graphite powder by weight %, as well as 0.5 to 2.0 parts by weight of a lubricant with respect to 100 parts by weight of the total weight of said powder. The iron based blended powder for powder metallurgy wherein the atomized alloy iron powder comprises, by weight %, 0.03 to 1.00% of Mn, 0.5 to 4.0% of Cr, 0.03 to 0.

Abstract: The present invention intends to provide an iron-based powder composition for powder metallurgy having excellent flowability at room temperature and a warm compaction temperature, having improved compactibility enabling lowering ejection force in compaction, to provide a process for producing the iron-based powder composition, and to provide a process for producing a compact of a high density from the iron-based powder composition. The iron-based powder composition comprises an iron-based powder, a lubricant, and an alloying powder, and at least one of the iron-based powder, the lubricant, and the alloying powder is coated with at least one surface treatment agent selected from the group of surface treatment agents of organoalkoxysilanes, organosilazanes, titanate coupling agents, fluorine-containing silicon silane coupling agents.

Abstract: An iron-based powder composition is produces in accordance with a method comprising the steps of: adding to iron-based and alloying powders, for a primary mixing, a surface treatment agent, and in addition, for a secondary mixing, a fatty acid amide and at least one lubricant, wherein the lubricant has a melting point higher than that of the fatty acid amide and can be, a thermoplastic resin, a thermoplastic elastomer, and inorganic or organic compounds having a layered crystal structure; heating and stirring up a mixture after the secondary mixing at a temperature above a melting point of the fatty acid amide to melt the fatty acid amide; cooling, while mixing, the mixture subjected to the heating and stirring process so that the alloying powder and a lubricant having a melting point higher than the fatty acid amide adhere to a surface of the iron base powder subjected to the surface treatment by an adhesive force of the melt; and adding at the time of the cooling, for a tertiary mixing, a metallic soap and

Abstract: An iron-based powder composition for powder metallurgy excellent in flowability and compactibility is produced in accordance with a method comprising the steps of: adding to iron-based and alloying powders, for a primary mixing, a surface treatment agent, and in addition, for a secondary mixing, a fatty acid amide and at least one lubricant, wherein the lubricant has a melting point higher than that of the fatty acid amide and can be a thermoplastic resin, a thermoplastic elastomer, and inorganic or organic compounds having a layered crystal structure; heating and stirring up a mixture after the secondary mixing at a temperature above a melting point of the fatty acid amide to melt the fatty acid amide; cooling, while mixing, the mixture subjected to the heating and stirring process so that the alloying powder and a lubricant having a melting point higher than the fatty acid amide adhere to a surface of the iron base powder subjected to the surface treatment by an adhesive force of the melt; and adding at the

Abstract: An iron-based powder mixture for powder metallurgy, comprising: an iron-based powder, and from 0.05 to 0.50% by weight of a thermoplastic resin powder which comprises 50% or more by weight of units of at least one monomer selected from the group consisting of acrylic esters, methacrylic esters, and aromatic vinyl compounds, and whose average primary particle size is from 0.03 to 5 .mu.m, whose average agglomeration particle size is from 5 to 50 .mu.m, and whose average molecular weight measured by the specific viscosity of a solution is from 30000 to 5000000.

Abstract: An iron based powder mixture for powder metallurgy is provided which can produce a sintered material having by far higher machinability and sliding properties than conventional sintered materials, and also a sintered material containing alloy elements but having adaptability to sizing even after sintering; it comprises an atomized iron powder comprising S in a content of 0.03 to 0.30 wt %, Mn in a content of 0.05 to 0.40 wt % and the balance Fe and incidental impurities, to which is added one or more than one B-containing compound powder selected from boron nitride (BN), boric acid (H.sub.3 BO.sub.3), boron oxide (B.sub.2 O.sub.3) and the like in an amount of 0.001 to 0.3 wt % expressed as B, and incorporated with an MnS powder in an amount of 0.05 to 1.0 wt %, optionally alloyed partially with or prealloyed with Ni, Mo and Cu.

Abstract: An iron-base mixture and method for powder metallurgy containing iron-base powder, an alloy powder including at least copper, copper oxide or both, and an organic substance for bonding the alloy powder to the iron-base powder, wherein said copper powder or copper oxide powder has a particle size of agglomeration, when evaluated by the micro-track method, of about 5 .mu.m to 28 .mu.m, and wherein the particles of copper or copper oxide have a primary particle size which, when evaluated by the BET method, is about 0.2 .mu.m to 1.5 .mu.m.

Abstract: Alloy steel powders capable of obtaining high strength in a sintered state and having excellent compacting compressibility and methods of manufacturing a sintered body. The alloy steel powder comprises, by wt %, about 0.5-2% of Cr, not greater than about 0.08% of Mn, about 0.1-0.6% of Mo, about 0.05-0.5% of V, not greater than about 0.015 of S, not greater than about 0.2% of O, and the balance being Fe and incidental impurities. The alloy steel powder is compacted and sintered at a temperature of about 1100.degree.-1300.degree. C. and then cooled at a cooling rate no higher than about 1.degree. C./s in a temperature range of from about 800.degree. C. to 400.degree. C. The alloy steel powder can contain Nb and/or Ti and one or more of Co, W and B. Additionally, Ni powder and/or Cu powder may be adhered and dispersed onto the surface of the alloy steel powder.

Abstract: A mixed iron powder for powder metallurgy containing less than about 0.1 wt % of Mn, about 0.08 to 0.15 wt % of S, a total of about 0.05 to 0.70 wt % of one or more compounds selected from MoO.sub.3 and WO.sub.3, about 0.50 to 1.50 wt % of graphite powder, and the balance Fe and incidental impurities. The mixed iron powder can be manufactured by an atomizing process using water, and be used to manufacture a sintered steel having excellent machinability, strength and toughness without forming soot, even if sintered in a hydrogen-containing atmosphere.

Abstract: Atomized steel powder having excellent machinability, containing about S 0.005 wt % to 0.3 wt %, Cr 0.03 wt % to 0.3 wt %, Mn 0.03 wt % to 0.5 wt %, O 0.30 wt % or less, and the balance Fe and incidental impurities, and sintered steel that can be manufactured therefrom. In particular, each of specific components is limited to a preferred range so that atomized steel powder exhibiting excellent machinability, dimensional accuracy and wear resistance and sintered steel that can be manufactured therefrom are provided.