GB1599081A - Powder for the powder metallurgical manufacture of soft magnetic components - Google Patents
Powder for the powder metallurgical manufacture of soft magnetic components Download PDFInfo
- Publication number
- GB1599081A GB1599081A GB7556/78A GB755678A GB1599081A GB 1599081 A GB1599081 A GB 1599081A GB 7556/78 A GB7556/78 A GB 7556/78A GB 755678 A GB755678 A GB 755678A GB 1599081 A GB1599081 A GB 1599081A
- Authority
- GB
- United Kingdom
- Prior art keywords
- powder
- phosphorus
- soft magnetic
- tensile strength
- particle size
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000000843 powder Substances 0.000 title claims description 58
- 238000004519 manufacturing process Methods 0.000 title claims description 15
- 229910052698 phosphorus Inorganic materials 0.000 claims description 51
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 48
- 239000000463 material Substances 0.000 claims description 27
- 239000002245 particle Substances 0.000 claims description 27
- 239000011574 phosphorus Substances 0.000 claims description 27
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 26
- 239000000203 mixture Substances 0.000 claims description 7
- 230000001419 dependent effect Effects 0.000 claims description 4
- 239000000654 additive Substances 0.000 claims description 3
- 230000000996 additive effect Effects 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical compound [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 description 12
- 238000000034 method Methods 0.000 description 6
- 238000005245 sintering Methods 0.000 description 4
- 238000005275 alloying Methods 0.000 description 3
- 230000000875 corresponding effect Effects 0.000 description 3
- 238000004663 powder metallurgy Methods 0.000 description 3
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 230000002542 deteriorative effect Effects 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 238000005029 sieve analysis Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000011343 solid material Substances 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
- H01F1/20—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/02—Making ferrous alloys by powder metallurgy
- C22C33/0207—Using a mixture of prealloyed powders or a master alloy
- C22C33/0214—Using a mixture of prealloyed powders or a master alloy comprising P or a phosphorus compound
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Dispersion Chemistry (AREA)
- Power Engineering (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Powder Metallurgy (AREA)
- Soft Magnetic Materials (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
Description
(54) POWDER FOR THE POWDER METALLURGICAL MANUFACTURE
OF SOFT MAGNETIC COMPONENTS
(71) We, HÖGANÄS AB, of Fack S-263 01 Höganäs, Sweden, a Swedish Joint Stock
Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
The invention relates to a powder for the powder metallurgical manufacture of soft magnetic components, and particularly concerns highly pure iron powders having large particle size with the addition of a phosphorus containing powder, especially intended for the powder metallurgical manufacturing of components satisfying great demands for soft magnetic properties.
Powder metallurgical manufacturing techniques are generally characterised by long series production of components having good dimensional accuracy. The manufacturing sequence is generally started by mixing a metallic powder, for example iron powder, if desired containing alloying elements in powder form, with a lubricant in order to simplify a subsequent compression operation. Thereby the powder mixture is compressed to a green compact, the shape of which approximately or exactly corresponds to the shape of the final component. Thereupon the green compact is heated and is retained at a temperature at which the green compact obtains, by means of sintering, its final characteristics with regard to strength, ductility etc. Basically, materials manufactured in this way differ from materials manufactured by the usual metallurgical way of casting by their porosity. Components satisfying the demands for good soft magnetic properties are usually manfactured from materials having iron as its main component. The most common manufacturing method is that wherein the components are manufactured from a piece of highly pure solid material, for example Armco-iron. However, the powder metallurgical technique is also used for the manufacture of such components because of the advantages that this method offers with regard to the saving of material, dimensional accuracy and the simplified shaping of the components. However, it has hitherto not been possible to obtain the same good soft magnetic properties of materials manufactured by means of powder metallurgy including iron as the main component, as for solid material having a corresponding composition.
Substantially, this difference is dependent on the porosity of the material manufactured having the powder metallurgical techniques.
According to the invention there is provided a powder for the powder metallurgical manufacture of soft magnetic components, comprising a highly pure iron powder in which the main portion of the powder has a particle size between 35 and 100 Tyler mesh (417 and 147 um), less than 5% of the powder has a particle size exceeding 35 Tyler mesh (417 Fm) and less than 20% of the powder has a particle size less than 100 Tyler mesh (147 lem), and in which the powder contains as an alloy additive up to 1.5% phosphorus.
Thus the invention makes it possible to obtain with a material manufactured using powder metallurgical techniques, soft magnetic properties which are about the same as the corresponding properties of highly pure solid iron, i.e. by using as the starting material an iron powder having a sieve analysis which is unusual for powder metallurgy in that the particles tend to be coarse. In addition to the fact that the iron powder must be coarse, a very low impurity content is required.
This highly pure iron powder, which is preferably manufactured by atomisation, should have an iron content in excess of 99.8%. Here, as well as in the following, "%" means "weight %". The contents of impurities, which are known to deteriorate the magnetic properties of iron, should in this iron powder by as low as possible and should preferably be: C < 0.01 %, O-total < 0.1 %, N < 0.005 C/o. The content of particles greater than 35
Tyler mesh (417 llm) does not exceed 5%, and the content of particles less than 100 Tyler mesh (147 llm) is less than 20%, preferably 10%.
Because of the very low content of particles less than 147 Rm, the mechanical properties of components manufactured from this coarse, highly pure iron powder are very low. If a higher strength is desired, it is not possible to increase the content of particles having a size less than 147 iim without simultaneously deteriorating the soft magnetic properties. This problem can be overcome by adding a powdered alloying component to the highly pure coarse iron powder, the alloying component producing, on the sintering, an increased strength without deteriorating the soft magnetic properties of the material thus produced.
It is known that ferrophosphorus in powder form which is mixed with the iron powder types normally used in powder metallurgy and having a particle size which is less than 147 clam, brings about, on sintering, an increased strength. See for example the specification of
United Kingdom Patent No. 1427070. However in contradistinction to the prior art and as appears from the following Examples, the addition of ferrophosphorus in powder form to the above highly pure coarse iron powder can make the strength of the sintered material five times higher, thereby not only retaining but even further enhancing the soft magnetic porperties. The total phosphorus content of the mixture should not exceed 1.5%. The maximum increase of the strength is obtained at a content of 0.3 % phosphorus. Preferably, the phosphorus is added as ferro-phosphorus powder.
After compression and sintering at conditions normal in connection with powder metallurgical manufacturing, such a powder mixture produces components having good mechanical properties and soft magnetic properties which are better than those of the corresponding material without phosphorus and dependent on the phosphorus content can be even better than the soft magnetic properties of solid highly pure iron.
The invention is hereinafter described with reference to the following specific Examples.
Example 1
Two iron powders having different particle size distributions were manufactured by atomising a highly pure iron melt, drying, after-reduction and sieving. Chemical analysis of these two iron powders gave the following composition: 0.047% 0, 0.004 % N, 0.003 % S, < 0.1 % C and balance Fe. The particles size distributions of these iron powders A and B were as follows:
Iron powder Sieve analysis Tyler mesh, %: > 35 35-100 < 100
A 1.3 97.4 1.3
B 0.0 3.6 96.4
These iron powders were mixed with ferrophosphorus containing 15% phosphorus and having a particle size less than 45 Rm, to a phosphorus content of 0.45 %. In the following powder A with an additionof 0.45 %. phosphorus is designated C and powder B with an addition of 0.45 % phosphorus is designated D.
The powders A to D, mixed with 0.8 % zinc stearate, were compressed at a pressure of 589 MPa to bars having the dimensions 55x10x10 mm and to tensile test bars. After burning-off the lubricant for 30 minutes at 400"C in air, the bars were sintered in a belt furnace for 60 minutes at 1120"C in hydrogen atmosphere. As the coercive force is a relevant measure as to the soft magnetic properties of a material, this was measured by means of a so-called coercimeter. The four materials showed the following coercive forces:
Material A 1.02 Oe
B 1.56 Oe
C 0.89 Oe
D 1.34 Oe
The above results show the great advantages which are obtained when using a coarse iron powder mixed with phosphrous. The low coercive force value of material C is about the same as the coercive force of Armco-iron which is about 0.9 Oe.
It has also been found that at the same time as the coercive force decreases the resistivity of the material increased when phosphorus is added, which results in decreasing eddy current losses, which means that the total magnetic losses are reduced.
The density, the tensile strength and the elongation at rupture appear from the following table:
Material Density Tensile strength Elongation at rupture
g/cm3 N/mm2
A 7.28 50 5 B 7.29 184 15.4
C 7.24 254 2.6
D 7.25 400 14.0
The strength properties given in this example show very low values for material A manufactured from iron powder having a low content of particles with a size less than 147 um. From the results it can also be seen that an addition of phosphorus to this powder improves the tensile strength about five times.
The results are shown graphically in Figures 1, 2 and 3 which respectively show coercive force, tensile strength and elongation at rupture as a function of the weight of particles having a size less than 100 Tyler mesh.
Example 2
An iron powder A according to Example 1 was mixed with ferrophosphorus containing 15% phosphorus and having a particle size less than 451rm to phosphorus contents of from 0.3 to 1.5 P. 0.8 % Zn-stearate was added to these mixtures. Test bars were compressed, burned-off and sintered in the same way as described in Example 1. The following results were obtained:
Material Density Tensile strength Elongation at rupture glum3 N/mm2
A + 0.30 % P 7.23 265 8.6
A + 0.45 % P 7.24 254 2.6
A + 0.60 % P 7.23 240 0.9
A + 1.00 % P 7.18 234 0.7
A + 1.50 % P 7.15 150 0.5
A + 0 % P acc.
to Example 1 7.28 50 5 These results show that the tensile strength of sintered bars having iron powder A as the basic material is substantially increased because of the addition of phosporus. The fact that this substantial increase of the tensile strength, which is dependent on the addition of phosphorus has been obtained together with an improvement of the sdft magnetic properties appears from the following table and Figures 4 and 5, which illustrate the tensile strength and the coercive force, respectively, as a function of the phosphorus content.
Material Coercive force
Oe
A + 0.30 % P 0.95
A + 0.45 % P 0.89
A + 0.60 % P 0.82
A + 1.00 % P 0.73
A + 1.50 % P 0.85
A + 0 % P acc. to
Example 1 1.02
All these coercive force values are very low and show that this material is extremely well suited for components wherein good soft magnetic properties are desired.
WHAT WE CLAIM IS:
1. A powder for the powder metallurgical manufacture of soft magnetic components, comprising a highly pure iron powder in which the main portion of the powder has a particle size between 35 and 100 Tyler mesh (417 and 147 Fm), less than 5% of the powder has a particle size exceeding 35 Tyler mesh (417 llm) and less than 20% of the powder has a particle size less than 100 Tyler mesh (147 um), and in which the powder contains as an
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (8)
1. A powder for the powder metallurgical manufacture of soft magnetic components, comprising a highly pure iron powder in which the main portion of the powder has a particle size between 35 and 100 Tyler mesh (417 and 147 Fm), less than 5% of the powder has a particle size exceeding 35 Tyler mesh (417 llm) and less than 20% of the powder has a particle size less than 100 Tyler mesh (147 um), and in which the powder contains as an
alloy additive up to 1.5 % phosphorus.
2. A powder according to Claim 1, in which less than 10% of the iron powder has a particle size less than 100 Tyler mesh (14711m).
3. A powder according to Claim 1 or Claim 2, in which the powder contains as an alloy additive between 0.15 and 1.0% phosphorus.
4. A powder according to any preceding claim, in which the phosphorus is added in the form of ferrophosphorus in powder form.
5. A powder according to Claim 4. said ferrophosphorus having a phosphorus content of about 15% and a particle size less than 45,us.
6. A powder for the powder metallurgical manufacture of soft magnetic components, according to claim 1 substantially as hereinbefore described with reference to and as shown in the Examples.
7. A powder for the powder metallurgical manufacture of soft magnetic components, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
8. A soft magnetic component whenever made from a powder according to any preceding claim.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7702084A SE407641B (en) | 1977-02-25 | 1977-02-25 | POWDER INTENDED FOR POWDER METALLURGIC MANUFACTURE OF SOFT MAGNETIC PRODUCTS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1599081A true GB1599081A (en) | 1981-09-30 |
Family
ID=20330554
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7556/78A Expired GB1599081A (en) | 1977-02-25 | 1978-02-24 | Powder for the powder metallurgical manufacture of soft magnetic components |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS53127310A (en) |
| CA (1) | CA1100788A (en) |
| DE (1) | DE2807602C2 (en) |
| ES (1) | ES467302A1 (en) |
| FR (1) | FR2381584A1 (en) |
| GB (1) | GB1599081A (en) |
| IT (1) | IT1101808B (en) |
| SE (1) | SE407641B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4236945A (en) * | 1978-11-27 | 1980-12-02 | Allegheny Ludlum Steel Corporation | Phosphorus-iron powder and method of producing soft magnetic material therefrom |
| DE10020083A1 (en) * | 2000-04-22 | 2001-10-31 | Bosch Gmbh Robert | Sintered soft magnetic material and process for its production |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB679413A (en) * | 1950-03-04 | 1952-09-17 | Metro Cutanit Ltd | Improvements relating to magnetic material with good electrical conductivity |
| DE2118053A1 (en) * | 1971-04-14 | 1972-10-26 | Brown, Boveri & Cie AG, 6800 Mann heim | Earth core for choke made from a mixture of ferromagnetic powder and insulating material binder |
| JPS4845472A (en) * | 1971-10-13 | 1973-06-29 | ||
| SE372293B (en) * | 1972-05-02 | 1974-12-16 | Hoeganaes Ab | |
| JPS518368A (en) * | 1974-07-09 | 1976-01-23 | Noryuki Ikeda | Burashiruino seizoho |
| DE2535377A1 (en) * | 1975-08-08 | 1977-02-24 | Huettermann | Sintered iron element absorbing vibration and noise - esp. for mounting brake shoes in motor vehicle disc brakes |
| JPS5442644A (en) * | 1977-09-09 | 1979-04-04 | Nippon Electric Co | Method of positioning electrodes of laminated condenser |
-
1977
- 1977-02-25 SE SE7702084A patent/SE407641B/en not_active IP Right Cessation
-
1978
- 1978-02-22 DE DE2807602A patent/DE2807602C2/en not_active Expired
- 1978-02-24 IT IT48186/78A patent/IT1101808B/en active
- 1978-02-24 CA CA297,696A patent/CA1100788A/en not_active Expired
- 1978-02-24 GB GB7556/78A patent/GB1599081A/en not_active Expired
- 1978-02-24 FR FR7805419A patent/FR2381584A1/en active Granted
- 1978-02-24 ES ES467302A patent/ES467302A1/en not_active Expired
- 1978-02-24 JP JP1996978A patent/JPS53127310A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| IT1101808B (en) | 1985-10-07 |
| JPS6323241B2 (en) | 1988-05-16 |
| SE7702084L (en) | 1978-08-26 |
| JPS53127310A (en) | 1978-11-07 |
| IT7848186A0 (en) | 1978-02-24 |
| ES467302A1 (en) | 1979-11-01 |
| DE2807602C2 (en) | 1986-10-16 |
| FR2381584A1 (en) | 1978-09-22 |
| DE2807602A1 (en) | 1978-10-19 |
| FR2381584B1 (en) | 1983-01-14 |
| SE407641B (en) | 1979-04-02 |
| CA1100788A (en) | 1981-05-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3864809A (en) | Process of producing by powder metallurgy techniques a ferritic hot forging of low flow stress | |
| JPH04231404A (en) | Method for powder metallurgy by means of optimized two-times press-two-times sintering | |
| US4190441A (en) | Powder intended for powder metallurgical manufacturing of soft magnetic components | |
| US3899319A (en) | Powder mixture for the production of alloy steel with a low content of oxide inclusions | |
| US4128420A (en) | High-strength iron-molybdenum-nickel-phosphorus containing sintered alloy | |
| US4090875A (en) | Ductile tungsten-nickel-alloy and method for manufacturing same | |
| GB1595346A (en) | Process for manufacturing iron based powder | |
| EP0200691B1 (en) | Iron-based powder mixture for a sintered alloy | |
| US5505760A (en) | Powder-metallurgical composition having good soft magnetic properties | |
| US4236945A (en) | Phosphorus-iron powder and method of producing soft magnetic material therefrom | |
| US4049429A (en) | Ferritic alloys of low flow stress for P/M forgings | |
| US4126452A (en) | Phosphorus containing steel powder and a method of manufacturing the same | |
| US4921665A (en) | Process for preparing powder metal parts with dynamic properties | |
| GB1599081A (en) | Powder for the powder metallurgical manufacture of soft magnetic components | |
| JPH08921B2 (en) | Pure iron powder for powder metallurgy with excellent compressibility and magnetic properties | |
| US3497347A (en) | Phosphorus containing iron powder | |
| US4585480A (en) | Material for the powder metallurgical manufacture of soft magnetic components | |
| US5918293A (en) | Iron based powder containing Mo, P and C | |
| CA1049296A (en) | Powder-metallurgy of cobalt containing brass alloys | |
| US4603028A (en) | Method of manufacturing sintered components | |
| JP3347773B2 (en) | Pure iron powder mixture for powder metallurgy | |
| JPH01172548A (en) | Iron-cobalt-type soft magnetic material | |
| JP3443911B2 (en) | Atomized iron powder for powder metallurgy | |
| KR101858795B1 (en) | Light sintered body having high strength and toughness and manufacturing method thereof | |
| JPH075921B2 (en) | Method for producing composite alloy steel powder with excellent compressibility |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19930224 |