CN104325133A - Nano iron powder sintering body containing nano ferroferric oxide and preparation method of nano iron powder sintering body - Google Patents
Nano iron powder sintering body containing nano ferroferric oxide and preparation method of nano iron powder sintering body Download PDFInfo
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- CN104325133A CN104325133A CN201410646653.7A CN201410646653A CN104325133A CN 104325133 A CN104325133 A CN 104325133A CN 201410646653 A CN201410646653 A CN 201410646653A CN 104325133 A CN104325133 A CN 104325133A
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Abstract
The invention discloses a nano iron powder sintering body containing a nano ferroferric oxide and a preparation method of the nano iron powder sintering body. The nano iron powder sintering body is prepared from the following raw materials by mass percentage: 80%-100% of nano ferroferric oxide powder and 0-20% of additive powder, wherein the additive powder is the powder containing one of C, Al, Si, Mn, Sn, Ni, Co, Cr, Mo, Cu and Nb and compound powder containing two or more of C, Al, Si, Mn, Sn, Ni, Co, Cr, Mo, Cu and Nb. The preparation method comprises the following steps: fully mixing the raw materials; then carrying out mold pressing, isostatic pressing or vibration molding; finally sintering in high-purity hydrogen or a mixed atmosphere of the high-purity hydrogen and nitrogen at 850-1,200 DEG C; carrying out heat preservation for 30-300 minutes. The preparation method is simple in process, rapid sintering of iron compound powder is achieved at relatively low temperature, wear-resistant alloy, high-temperature alloy, silicon steel, high-strength spare parts for automobiles and other special steel products can be manufactured, and the production cost is low.
Description
Technical field
The present invention relates to nanometer iron powder sintered body, refer to a kind of nanometer iron powder sintered body containing nano ferriferrous oxide and preparation method thereof particularly.
Background technology
In field of powder metallurgy, metal powder is pressurizeed in metal pattern, shaping after, carry out sintering and the sintered body made, precision can manufacture the mechanical part of complicated shape well.Therefore, in the manufacture requiring the automobile component of high dimensional accuracy, antifriction alloy, high temperature alloy and other specific use parts, sintered body can be applied widely.
Publication number is that the Chinese invention patent of CN101772389A discloses " powder used in metallurgy iron system's mixed-powder and iron powder sintering body ", be with containing iron-based powder, graphite powder, copper powder and composite oxides for raw material, realize below 1000 DEG C sintering.Publication number is that the Chinese invention patent of CN101733400A discloses " high-strength composition iron powder and its sintered component of use ", with iron powder primary raw material, add a certain amount of Mn, Fe-Mn (particle diameter less than 45 microns), Cu and powdered graphite, more than the fusing point of Cu, in less than 1300 DEG C temperature ranges, realize sintering.Publication number is that the Chinese utility model patent of CN201141401Y discloses " a kind of bimetallic bearing of copper-clad iron powder sintering ", sintering has the wearing layer of copper-clad iron powder on a surface of a steel sheet, form stacked composite, and make axle sleeve or flat board with this composite, sintering has the surface of copper-clad iron powder to be the rubbing surface of bearing.
In sum, the research of iron system composite powder sintered body, mainly concentrates on the relatively low copper powder of employing fusing point as sintering aid aspect, cannot meet the use needs of high strength parts and other steel for special purposes products.
Summary of the invention
Object of the present invention is exactly to overcome the deficiency existing for prior art, nanometer iron powder sintered body providing a kind of nanometer to contain nano ferriferrous oxide and preparation method thereof.
The fusing point of general material is, under a certain pressure, pure material solid-state and liquid in balance time temperature, that is, under this pressure and melting temperature, pure material be that solid-state chemical potential is equal with the chemical potential be in a liquid state.Concerning the pure object of bulk, its chemical potential is the function of temperature and pressure.
And nano particle due to particle diameter little, specific surface free energy is high, therefore its chemical potential is higher than the blocks of solid under the same terms a lot, and result causes its fusing point and sintering temperature to be significantly less than the blocks of solid of same material, and the particle diameter of particle is less, its fusing point and sintering temperature lower.Such as, the fusing point of bulk Pb is 600K, and the fusing point of 20 nanometer spherical Pb particles reduces 288K, and nano-Ag particles is starting fusing lower than 373K, and the fusing point of conventional Ag is up to 1273K.
We are found by experimental study, when the particle diameter of nanometer iron powder is less than 100 nanometer, its fusing point can reduce, simultaneously, under the specific condition of high-purity hydrogen or high-purity hydrogen and nitrogen mixture atmosphere, after metal oxide back becomes simple substance particle, its activity is higher, more easily and other metals or oxide react, sinter.Utilize this principle to design, produce various metals sintered powder, to meet the use needs of high strength parts and other steel for special purposes products.
For achieving the above object, the nanometer iron powder sintered body containing nano ferriferrous oxide designed by the present invention, it is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 100%, additive powder 0 ~ 20%, described additive powder is containing a kind of powder in C, Al, Si, Mn, Sn, Ni, Co, Cr, Mo, Cu, Nb element or two kinds and two or more composite powders.
Preferably, the nanometer iron powder sintered body containing nano ferriferrous oxide is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 90 ~ 95%, graphite powder 0.05 ~ 0.5%, Al powder 1.0 ~ 5.0%, Si powder 1.0 ~ 5.0%, Mn powder 1.0 ~ 4.5%.
Preferably, the nanometer iron powder sintered body containing nano ferriferrous oxide is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 95%, Ni powder 5 ~ 20%, Co powder 0 ~ 10%.
Preferably, the nanometer iron powder sintered body containing nano ferriferrous oxide is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 90%, Ni powder 5 ~ 15%, Cr powder 5 ~ 15%, Mn powder 0 ~ 5%.
Preferably, the nanometer iron powder sintered body containing nano ferriferrous oxide is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 90 ~ 95%, Al powder 1.0 ~ 1.5%, Si powder 2.0 ~ 5.0%, Mn powder 1.0 ~ 3.5%, Sn powder 0.1 ~ 1.0%, Cu powder 0.2 ~ 0.8%.
Preferably, the nanometer iron powder sintered body containing nano ferriferrous oxide is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 90%, graphite powder 0.1 ~ 0.5%, Mn powder 1.0 ~ 3.5%, Cr powder 5 ~ 15%, Mo powder 2 ~ 8%.
In the present invention, the average grain diameter of described nano ferriferrous oxide powder is less than 80 nanometers, purity more than 98%.The average grain diameter of described additive powder is less than 10 microns, purity more than 99%.
The preparation method of the above-mentioned nanometer iron powder sintered body containing nano ferriferrous oxide: first raw material is fully mixed, then mold pressing, isostatic pressed or vibration moulding is carried out, finally in the mixed atmosphere of high-purity hydrogen or high-purity hydrogen and nitrogen, sinter at sintering temperature 850 ~ 1200 DEG C, be incubated 30 ~ 300 minutes.
In mixed atmosphere of the present invention, hydrogen volume percent concentration is 20 ~ 99%, and nitrogen concentration of volume percent is 1 ~ 80%.
Found by experimental study, when the particle diameter of nano ferriferrous oxide powder is less than 80 nanometer, its fusing point can reduce, simultaneously, under the specific condition of the mixed atmosphere of high-purity hydrogen or high-purity hydrogen and nitrogen, after nano ferriferrous oxide powder reduction becomes fe, its activity is higher, even occurs liquid phase, more easily and other metals or oxide react, sinter, utilize this principle to design, produce various metals sintered powder.
Beneficial effect of the present invention is: adopt technique scheme, present invention process is simple, under low temperature, realize the sintering of quick iron system composite powder, antifriction alloy, high temperature alloy, silicon steel, automobile high-strength parts and other steel for special purposes products can be manufactured, low production cost.
Detailed description of the invention
In order to explain the present invention better, below in conjunction with specific embodiment, the present invention is described in further detail, but they do not form restriction to the present invention.
Embodiment 1
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 89.5%, additive powder 10.5%; Wherein, additive powder is graphite powder 0.5%, Al powder 1.5%, Si powder 5.0%, Mn powder 3.5%.
Preparation method: first fully mixed with additive powder by nano ferriferrous oxide powder, then carries out compression molding, finally in high-purity hydrogen atmosphere, sinters at sintering temperature 900 DEG C, temperature retention time 120 minutes.
Embodiment 2
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 95%, additive powder 5%; Wherein, additive powder is graphite powder 0.1%, Al powder 2.0%, Si powder 1.4%, Mn powder 1.5%.
Preparation method: first fully mixed with additive powder by nano ferriferrous oxide powder, then carries out compression molding, finally in high-purity hydrogen atmosphere, sinters at sintering temperature 950 DEG C, temperature retention time 30 minutes.
Embodiment 3
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 94%, additive powder 6%; Wherein, additive powder is graphite powder 0.3%, Al powder 1.5%, Si powder 2.2%, Mn powder 2.0%.
Preparation method: first nano ferriferrous oxide powder is fully mixed with additive powder, then compression molding is carried out, last in high-purity hydrogen and nitrogen mixture atmosphere, hydrogen volume percent concentration is 90%, nitrogen concentration of volume percent is 10%, sinter at sintering temperature 900 DEG C, temperature retention time 30 minutes.
Embodiment 4
The raw material of the nanometer iron powder sintered body containing nano ferriferrous oxide is 100% nano ferriferrous oxide powder.
Preparation method: nano ferriferrous oxide powder is carried out compression molding, in high-purity hydrogen atmosphere, sinters, temperature retention time 120 minutes at sintering temperature 850 DEG C.
Embodiment 5
The raw material of the nanometer iron powder sintered body containing nano ferriferrous oxide is 100% nano ferriferrous oxide powder.
Preparation method: nano ferriferrous oxide powder is carried out compression molding, in high-purity hydrogen and nitrogen mixture atmosphere, hydrogen volume percent concentration is 70%, and nitrogen concentration of volume percent is 30%, sinter at sintering temperature 900 DEG C, temperature retention time 120 minutes.
Embodiment 6
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 85%, additive powder 15%; Wherein, additive powder is Ni powder 5%, Co powder 10%.
Preparation method: first fully mixed with additive powder by nano ferriferrous oxide powder, then carries out vibration moulding, finally in high-purity hydrogen, sinters at sintering temperature 1000 DEG C, temperature retention time 300 minutes.
Embodiment 7
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 80%, additive powder 20%; Wherein, additive powder is Ni powder 20%.
Preparation method: first fully mixed with additive powder by nano ferriferrous oxide powder, then carries out isostatic compaction, finally in high-purity hydrogen, sinters at sintering temperature 1050 DEG C, temperature retention time 120 minutes.
Embodiment 8
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 80%, additive powder 20%; Wherein, additive powder is Ni powder 10%, Co powder 10%.
Preparation method: first nano ferriferrous oxide powder is fully mixed with additive powder, then compression molding is carried out, last in high-purity hydrogen and nitrogen mixture atmosphere, hydrogen volume percent concentration is 50%, nitrogen concentration of volume percent is 50%, sinter at sintering temperature 1100 DEG C, temperature retention time 60 minutes.
Embodiment 9
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 80%, additive powder 20%; Wherein, additive powder is Ni powder 15%, Cr powder 5%, Mn powder 5%.
Preparation method: first fully mixed with additive powder by nano ferriferrous oxide powder, then carries out compression molding, finally in high-purity hydrogen atmosphere, sinters at sintering temperature 1050 DEG C, temperature retention time 120 minutes.
Embodiment 10
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 80%, additive powder 20%; Wherein, additive powder is Ni powder 5%, Cr powder 15%.
Preparation method: first nano ferriferrous oxide powder is fully mixed with additive powder, then vibration moulding is carried out, in high-purity hydrogen and nitrogen mixture atmosphere, hydrogen volume percent concentration is 40%, nitrogen concentration of volume percent is 60%, sinter at sintering temperature 1100 DEG C, be incubated 60 minutes.
Embodiment 11
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 95%, additive powder 5%; Wherein, additive powder is Al powder 1.0%, Si powder 2.0%, Mn powder 1.0%, Sn powder 0.6%, Cu powder 0.4%.
Preparation method: first fully mixed with additive powder by nano ferriferrous oxide powder, then carries out compression molding, finally in high-purity hydrogen atmosphere, sinters at sintering temperature 1150 DEG C, temperature retention time 60 minutes.
Embodiment 12
The composition of raw materials of the nanometer iron powder sintered body containing nano ferriferrous oxide, is by mass percentage: nano ferriferrous oxide powder 80%, additive powder 20%; Wherein, additive powder is graphite powder 0.5%, Mn powder 2.5%, Cr powder 15%, Mo powder 2%.
Preparation method: first fully mixed with additive powder by nano ferriferrous oxide powder, then carries out compression molding, finally in high-purity hydrogen atmosphere, sinters at sintering temperature 1050 DEG C, temperature retention time 120 minutes.
Claims (10)
1. the nanometer iron powder sintered body containing nano ferriferrous oxide, it is characterized in that, it is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 100%, additive powder 0 ~ 20%, described additive powder is containing a kind of powder in C, Al, Si, Mn, Sn, Ni, Co, Cr, Mo, Cu, Nb element or two kinds and two or more composite powders.
2. the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1, it is characterized in that, it is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 90 ~ 95%, graphite powder 0.05 ~ 0.5%, Al powder 1.0 ~ 5.0%, Si powder 1.0 ~ 5.0%, Mn powder 1.0 ~ 4.5%.
3. the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1, it is characterized in that, it is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 95%, Ni powder 5 ~ 20%, Co powder 0 ~ 10%.
4. the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1, it is characterized in that, it is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 90%, Ni powder 5 ~ 15%, Cr powder 5 ~ 15%, Mn powder 0 ~ 5%.
5. the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1, it is characterized in that, it is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 90 ~ 95%, Al powder 1.0 ~ 1.5%, Si powder 2.0 ~ 5.0%, Mn powder 1.0 ~ 3.5%, Sn powder 0.1 ~ 1.0%, Cu powder 0.2 ~ 0.8%.
6. the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1, it is characterized in that, it is formulated by following raw material by mass percentage: nano ferriferrous oxide powder 80 ~ 90%, graphite powder 0.1 ~ 0.5%, Mn powder 1.0 ~ 3.5%, Cr powder 5 ~ 15%, Mo powder 2 ~ 8%.
7. the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1, is characterized in that: the average grain diameter of described nano ferriferrous oxide powder is less than 80 nanometers, purity more than 98%.
8. the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1 and 2, is characterized in that: the average grain diameter of described additive powder is less than 10 microns, purity more than 99%.
9. the preparation method of the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 1, it is characterized in that: first raw material is fully mixed, then mold pressing, isostatic pressed or vibration moulding is carried out, finally in the mixed atmosphere of high-purity hydrogen or high-purity hydrogen and nitrogen, sinter at sintering temperature 850 ~ 1200 DEG C, be incubated 30 ~ 300 minutes.
10. the preparation method of the nanometer iron powder sintered body containing nano ferriferrous oxide according to claim 4, it is characterized in that: in described mixed atmosphere, hydrogen volume percent concentration is 20 ~ 99%, and nitrogen concentration of volume percent is 1 ~ 80%.
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CN113976875A (en) * | 2021-10-12 | 2022-01-28 | 河北敬业立德增材制造有限责任公司 | High-temperature liquid phase sintering combined gold powder for powder metallurgy iron-based parts and manufacturing method thereof |
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CN101772389A (en) * | 2007-08-03 | 2010-07-07 | 株式会社神户制钢所 | Powder used in metallurgy iron is mixed-powder and iron powder sintered body |
CN102603198A (en) * | 2012-03-07 | 2012-07-25 | 南京工业大学 | Inorganic electromagnetic wave absorbing material and preparation method thereof |
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Patent Citations (5)
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CN1057800A (en) * | 1991-07-08 | 1992-01-15 | 孔凯旋 | Spongy iron heat diffusion body and manufacture method thereof |
CN1532965A (en) * | 2003-03-25 | 2004-09-29 | 勇 张 | Activated iron electrode |
CN101246773A (en) * | 2007-02-12 | 2008-08-20 | 北京有色金属研究总院 | High-efficiency soft magnetic material and method for producing the same |
CN101772389A (en) * | 2007-08-03 | 2010-07-07 | 株式会社神户制钢所 | Powder used in metallurgy iron is mixed-powder and iron powder sintered body |
CN102603198A (en) * | 2012-03-07 | 2012-07-25 | 南京工业大学 | Inorganic electromagnetic wave absorbing material and preparation method thereof |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN113976875A (en) * | 2021-10-12 | 2022-01-28 | 河北敬业立德增材制造有限责任公司 | High-temperature liquid phase sintering combined gold powder for powder metallurgy iron-based parts and manufacturing method thereof |
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