GB1565983A - Phosphorus steel powder and a method of manufacturing the same - Google Patents
Phosphorus steel powder and a method of manufacturing the same Download PDFInfo
- Publication number
- GB1565983A GB1565983A GB43996/76A GB4399676A GB1565983A GB 1565983 A GB1565983 A GB 1565983A GB 43996/76 A GB43996/76 A GB 43996/76A GB 4399676 A GB4399676 A GB 4399676A GB 1565983 A GB1565983 A GB 1565983A
- Authority
- GB
- United Kingdom
- Prior art keywords
- powder
- phosphorus
- content
- iron
- mixture
- 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 48
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 title claims description 39
- 229910052698 phosphorus Inorganic materials 0.000 title claims description 39
- 239000011574 phosphorus Substances 0.000 title claims description 39
- 229910000831 Steel Inorganic materials 0.000 title description 9
- 239000010959 steel Substances 0.000 title description 9
- 238000004519 manufacturing process Methods 0.000 title description 3
- 239000002245 particle Substances 0.000 claims description 25
- 239000000203 mixture Substances 0.000 claims description 22
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 18
- 239000012535 impurity Substances 0.000 claims description 15
- 238000005275 alloying Methods 0.000 claims description 10
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 8
- 239000004411 aluminium Substances 0.000 claims description 8
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 8
- 229910052782 aluminium Inorganic materials 0.000 claims description 8
- DPTATFGPDCLUTF-UHFFFAOYSA-N phosphanylidyneiron Chemical compound [Fe]#P DPTATFGPDCLUTF-UHFFFAOYSA-N 0.000 claims description 8
- 229910052710 silicon Inorganic materials 0.000 claims description 8
- 239000010703 silicon Substances 0.000 claims description 8
- 238000005204 segregation Methods 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 4
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims description 4
- 229910052748 manganese Inorganic materials 0.000 claims description 4
- 239000011572 manganese Substances 0.000 claims description 4
- 238000002156 mixing Methods 0.000 claims description 4
- 238000009826 distribution Methods 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 2
- 239000000956 alloy Substances 0.000 claims description 2
- 229910045601 alloy Inorganic materials 0.000 claims description 2
- 229910021529 ammonia Inorganic materials 0.000 claims description 2
- 239000012141 concentrate Substances 0.000 claims description 2
- 239000012467 final product Substances 0.000 claims description 2
- 238000000227 grinding Methods 0.000 claims description 2
- 229940059904 light mineral oil Drugs 0.000 claims description 2
- 239000000155 melt Substances 0.000 claims description 2
- 239000003921 oil Substances 0.000 claims description 2
- 239000010936 titanium Substances 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
- 238000005245 sintering Methods 0.000 description 5
- 239000007791 liquid phase Substances 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 238000004663 powder metallurgy Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
Classifications
-
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/17—Metallic particles coated with metal
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Powder Metallurgy (AREA)
Description
(54) A PHOSPHORUS STEEL POWDER AND A METHOD OF
MANUFACTURING THE SAME
(71) We, HOGANAS AB, a Company organised under the laws of Sweden, of
Fack, 263 01 Höganäs, Sweden, 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 present invention relates to phosphorus steel powder mixtures to be used in powder metallurgy. In addition to iron and phosphorus these powder mixtures can contain other alloying elements common in this technique, such as copper, nickel, molybdenum, chromium and carbon.
The use of phosphorus as an alloying element in powder metallurgy has been known since the nineteen forties. Sintered steel alloyed with phosphorus has substantially improved strength characteristics in relation to non-alloyed sintered steel.
Already at an early date there were for this object used mixtures of pure iron powder and ferrophosphorus powder. However, the ferrophosphorus first used had a composition which made it extremely hard and caused a considerable wearing of the tools. This drawback has been reduced to an acceptable degree by using a ferrophosphorus powder having a lower content of phosphorus and thereby reduced hardness see for example Swedish Patent No.
372,293.
However, sintered details manufactured by pressing and sintering such steel powder mixtures sometimes have an unacceptable brittleness. This is revealed for example by the fact that a population of sintered test bars made from these mixtures can comprise individuals having extremely reduced mechanical characteristics especially with regard to impact strength and permanent strain after rupture (break elongation). As the advantage of phosphorus alloyed sintered steels is high strength in combination with very good strain characteristics the above brittleness risks are very serious.
Said brittleness risk has shown up to be present when the ferrophosphorus is of such composition that there is established a liquid phase at the sintering temperature.
At the usually used sintering temperatures, 1040"C and above that, this fact provides that phosphorus contents of more than 2.8 % in the ferrophosphorus give a sintered material having an increased brittleness risk. The fact that ferrophosphorus having a high phosphorus content is used in spite of this drawback is dependent on the favourable sintering process which is provided by the liquid phase and the favourable distribution of the phosphorus in turn providing for a rapid indiffusion thereof which is obtained because of the fact that the ferrophosphorus provides for a liquid phase.
Thus, the object of the present invention is to solve said problems with regard to the brittleness of sintered steel manufactured from a mixture of iron powder and a ferrophophorus powder having a phosphorus content exceeding 2.8 wt. %. The solution of the problem has proved to reside in the use of a ferrophosphorus powder having a low content of impurities, especially impurities sensititve to oxidation.
A further improvement can be obtained if the ferrophosphorus powder also has a small maximum particle size.
A phosphorus steel powder according to the invention for manufacturing sintered details having an extremely small tendency to brittleness ruptures consists of iron or steel powder substantially free from phosphorus, mixed with a ferrophosphorus powder in total containing in all less than 4%, preferably less than 3% impurities which are at the sintering temperature more easily oxidized than the main components iron and phosphorus. Further more, the particles of the ferrophosphorus powder shall have a maximum size of 20 pm, preferably a maximum size of 10 um. The phosphorus content of the ferrophosphorus powder shall exceed 2.8% and in order to reduce the wearing of the tools the phosphorus content shall preferably be less than 17%. If the ferrophosphorus powder is manufactured by grinding a workpiece the phosphorus content should exceed 12% and should preferably be between 14 and 16%. The phosphorus content of the mixture is between 0.2 and 1.5%.
It is often the case that there is a great difference between the particle sizes of the powder components in the mixture leading to an especialy great risk of segregation and thereby of a discontinuous distribution of the powder components. In order to reduce the tendency of the mixture to segregate after the mixing operation 50-200 g of a light mineral oil per metric ton powder can be added during the mixing operation. Thereby the fine alloying particles can adhere to the coarser iron powder particles.
In order to improve the protection against segregation the iron-ferrophosphorus mixture is heated with or without the addition of oil in a reducing atmosphere to a temperature of between 650 and 900"C for a period of 15 min. to 2 hours. Thereby, the powder is loosely sintered together so that a following cautious disintegration has to be carried out in order to restore the original particle size.
The powder provided in this way has iron particles with particles of the fine grained ferrophosphorus powder sintered thereto.
The methods described above in order to avoid segregation can be performed to a mixture having more phosphorus powder.
The concentrate so obtained can be mixed with the iron powder to provide for the desired phosphorus content in the final product.
The critical contents of the impurities appear from the following examples.
Example I
Three melts of iron-phosphorus including 15.5-16.5% phosphorus and controlled contents of silicon of 0.02, 0.17, 0.75 and 4.81% and additional impurity contents of '0.01% were manufactured and were allowed to solidify. Thereupon, they were ground to a powder from which two size classes were taken out, 0-10 pm and 10-40 stem. These phosphorus powders were mixed with extremely pure iron powder so that the mixture had a phosphorus content of 0.6% whereupon the mixture was compressed to impact strength test bars without indications of fracture having a size of 55 x 10 z 10 mm. The bars were sintered in cracked ammonia at 1120"C for 1 hour. The impact strength was tested at room temperature by means of a Charpy pendulum hammer. The result is shown in
Fig. 1 wherein the impact strength (I) relates to the mean value including the standard deviation for seven bars.
The curves clearly show the advantage of the phosphorus powder having partly a small particle size and partly a low silicon content. The silicon content shall be less than 0.5%, preferably less than 0.2%, for giving the impact strength a stable high value. However, the silicon content shall not be too low but exceed 0.05%, preferably exceed 0.1%.
Example 2
Iron-phosphorus alloying powder having aluminium as the only impurity element was manufactured in the same way as according to the preceding example. Three different contents of aluminium were used: 0.015, 0.03, 0.8 and 4.8%. Also powders having two different particle sizes, namely 0-10 ,(a.m and 1040 ,um, were manufactured.
The further treatment and the return of the results are the same as according to example 1, see Fig. 2.
The same conclusion concerning the particle size can be drawn from this example as from example 1. Also according to this example the toughness is better when the impurity contents are low. A suitable maximum content of aluminium in the iron-phosphorus-alloying powder is 3%, preferably 2%, and a suitable minimum aluminium content is 0.02%.
Example 3
The same tests as according to the above examples were conducted with ironphosphorus-alloys, this time having manganese as the only impurity element with a content of 0.01, 0.07, 0.68 and 5.0%.
The phosphorus content varied between 17.2 and 17.5%. The result appears from
Fig. 3.
Once more the example shows the importance of a small particle size of the iron-phosphorus alloying powder. Furthermore, the manganese content should be less than 0.25%, preferably less than 0.15%, and higher than 0.03%, preferably higher than 0.05%.
Example 4
The same tests as according to the above examples were conducted. The phosphorus content of the iron-phosphorus powders was 16.7-17.6% while the only impurity element this time was titanium in the amounts of 0.01, 0.02, 1.0 and 4.4%. The result appears from Fig. 4.
Also this example shows, even if not as striking as the previous examples, that the particle size of the iron-phosphoruspowder shall be low. Also the content of
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (4)
- **WARNING** start of CLMS field may overlap end of DESC **.more, the particles of the ferrophosphorus powder shall have a maximum size of 20 pm, preferably a maximum size of 10 um. The phosphorus content of the ferrophosphorus powder shall exceed
- 2.8% and in order to reduce the wearing of the tools the phosphorus content shall preferably be less than 17%. If the ferrophosphorus powder is manufactured by grinding a workpiece the phosphorus content should exceed 12% and should preferably be between 14 and 16%. The phosphorus content of the mixture is between 0.2 and 1.5%.It is often the case that there is a great difference between the particle sizes of the powder components in the mixture leading to an especialy great risk of segregation and thereby of a discontinuous distribution of the powder components. In order to reduce the tendency of the mixture to segregate after the mixing operation 50-200 g of a light mineral oil per metric ton powder can be added during the mixing operation. Thereby the fine alloying particles can adhere to the coarser iron powder particles.In order to improve the protection against segregation the iron-ferrophosphorus mixture is heated with or without the addition of oil in a reducing atmosphere to a temperature of between 650 and 900"C for a period of 15 min. to 2 hours. Thereby, the powder is loosely sintered together so that a following cautious disintegration has to be carried out in order to restore the original particle size.The powder provided in this way has iron particles with particles of the fine grained ferrophosphorus powder sintered thereto.The methods described above in order to avoid segregation can be performed to a mixture having more phosphorus powder.The concentrate so obtained can be mixed with the iron powder to provide for the desired phosphorus content in the final product.The critical contents of the impurities appear from the following examples.Example I Three melts of iron-phosphorus including 15.5-16.5% phosphorus and controlled contents of silicon of 0.02, 0.17, 0.75 and 4.81% and additional impurity contents of '0.01% were manufactured and were allowed to solidify. Thereupon, they were ground to a powder from which two size classes were taken out, 0-10 pm and 10-40 stem. These phosphorus powders were mixed with extremely pure iron powder so that the mixture had a phosphorus content of 0.6% whereupon the mixture was compressed to impact strength test bars without indications of fracture having a size of 55 x 10 z 10 mm. The bars were sintered in cracked ammonia at 1120"C for 1 hour. The impact strength was tested at room temperature by means of a Charpy pendulum hammer. The result is shown in Fig. 1 wherein the impact strength (I) relates to the mean value including the standard deviation for seven bars.The curves clearly show the advantage of the phosphorus powder having partly a small particle size and partly a low silicon content. The silicon content shall be less than 0.5%, preferably less than 0.2%, for giving the impact strength a stable high value. However, the silicon content shall not be too low but exceed 0.05%, preferably exceed 0.1%.Example 2 Iron-phosphorus alloying powder having aluminium as the only impurity element was manufactured in the same way as according to the preceding example. Three different contents of aluminium were used: 0.015, 0.03, 0.8 and 4.8%. Also powders having two different particle sizes, namely 0-10 ,(a.m and 1040 ,um, were manufactured.The further treatment and the return of the results are the same as according to example 1, see Fig. 2.The same conclusion concerning the particle size can be drawn from this example as from example 1. Also according to this example the toughness is better when the impurity contents are low. A suitable maximum content of aluminium in the iron-phosphorus-alloying powder is 3%, preferably 2%, and a suitable minimum aluminium content is 0.02%.Example 3 The same tests as according to the above examples were conducted with ironphosphorus-alloys, this time having manganese as the only impurity element with a content of 0.01, 0.07, 0.68 and 5.0%.The phosphorus content varied between 17.2 and 17.5%. The result appears from Fig.
- 3.Once more the example shows the importance of a small particle size of the iron-phosphorus alloying powder. Furthermore, the manganese content should be less than 0.25%, preferably less than 0.15%, and higher than 0.03%, preferably higher than 0.05%.Example 4 The same tests as according to the above examples were conducted. The phosphorus content of the iron-phosphorus powders was 16.7-17.6% while the only impurity element this time was titanium in the amounts of 0.01, 0.02, 1.0 and
- 4.4%. The result appears from Fig. 4.Also this example shows, even if not as striking as the previous examples, that the particle size of the iron-phosphoruspowder shall be low. Also the content of
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7511915A SE410983B (en) | 1975-10-24 | 1975-10-24 | PHOSPHORUS STABLE POWDER AND WAY TO MANUFACTURE THIS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1565983A true GB1565983A (en) | 1980-04-30 |
Family
ID=20325892
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB43996/76A Expired GB1565983A (en) | 1975-10-24 | 1976-10-22 | Phosphorus steel powder and a method of manufacturing the same |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS5284106A (en) |
| AU (1) | AU513171B2 (en) |
| BE (1) | BE847545A (en) |
| CA (1) | CA1071438A (en) |
| DE (1) | DE2648261A1 (en) |
| ES (1) | ES452674A1 (en) |
| FR (1) | FR2328778A1 (en) |
| GB (1) | GB1565983A (en) |
| IT (1) | IT1069591B (en) |
| SE (1) | SE410983B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119265407A (en) * | 2024-10-08 | 2025-01-07 | 江苏沙钢钢铁有限公司 | A method for treating magnetic separation powder by sintering |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4115158A (en) * | 1977-10-03 | 1978-09-19 | Allegheny Ludlum Industries, Inc. | Process for producing soft magnetic material |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2923622A (en) * | 1956-06-26 | 1960-02-02 | Nat U S Radiator Corp | Powder metallurgy |
| GB1204548A (en) * | 1967-11-03 | 1970-09-09 | Kennecott Copper Corp | Ferrous metal product useful as a precipitant and process of manufacturing it |
| JPS5213162B2 (en) * | 1972-04-22 | 1977-04-12 | ||
| SE372293B (en) * | 1972-05-02 | 1974-12-16 | Hoeganaes Ab |
-
1975
- 1975-10-24 SE SE7511915A patent/SE410983B/en not_active IP Right Cessation
-
1976
- 1976-10-22 BE BE171712A patent/BE847545A/en not_active IP Right Cessation
- 1976-10-22 GB GB43996/76A patent/GB1565983A/en not_active Expired
- 1976-10-22 CA CA263,945A patent/CA1071438A/en not_active Expired
- 1976-10-23 ES ES452674A patent/ES452674A1/en not_active Expired
- 1976-10-25 JP JP12738976A patent/JPS5284106A/en active Pending
- 1976-10-25 IT IT51873/76A patent/IT1069591B/en active
- 1976-10-25 FR FR7632114A patent/FR2328778A1/en active Granted
- 1976-10-25 AU AU18986/76A patent/AU513171B2/en not_active Expired
- 1976-10-25 DE DE19762648261 patent/DE2648261A1/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119265407A (en) * | 2024-10-08 | 2025-01-07 | 江苏沙钢钢铁有限公司 | A method for treating magnetic separation powder by sintering |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2648261A1 (en) | 1977-04-28 |
| CA1071438A (en) | 1980-02-12 |
| ES452674A1 (en) | 1978-06-01 |
| FR2328778B1 (en) | 1981-08-21 |
| JPS5284106A (en) | 1977-07-13 |
| AU513171B2 (en) | 1980-11-20 |
| BE847545A (en) | 1977-02-14 |
| IT1069591B (en) | 1985-03-25 |
| SE7511915L (en) | 1977-04-25 |
| FR2328778A1 (en) | 1977-05-20 |
| SE410983B (en) | 1979-11-19 |
| DE2648261C2 (en) | 1989-11-09 |
| AU1898676A (en) | 1978-05-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| 49R | Reference inserted (sect. 9/1949) | ||
| SP | Amendment (slips) printed | ||
| PCNP | Patent ceased through non-payment of renewal fee |