GB2165553A - Steel powder compositions and sintered products - Google Patents
Steel powder compositions and sintered products Download PDFInfo
- Publication number
- GB2165553A GB2165553A GB08425566A GB8425566A GB2165553A GB 2165553 A GB2165553 A GB 2165553A GB 08425566 A GB08425566 A GB 08425566A GB 8425566 A GB8425566 A GB 8425566A GB 2165553 A GB2165553 A GB 2165553A
- Authority
- GB
- United Kingdom
- Prior art keywords
- powder
- titanium
- hafnium
- steel
- article
- 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.)
- Withdrawn
Links
- 239000000843 powder Substances 0.000 title claims abstract description 34
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 23
- 239000010959 steel Substances 0.000 title claims abstract description 23
- 239000000203 mixture Substances 0.000 title abstract description 6
- 239000002245 particle Substances 0.000 claims abstract description 18
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052735 hafnium Inorganic materials 0.000 claims abstract description 15
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000010936 titanium Substances 0.000 claims abstract description 15
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 15
- 239000000654 additive Substances 0.000 claims abstract description 12
- 238000005245 sintering Methods 0.000 claims abstract description 11
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 10
- 150000001247 metal acetylides Chemical class 0.000 claims abstract description 8
- 229910001315 Tool steel Inorganic materials 0.000 claims abstract description 7
- 238000004519 manufacturing process Methods 0.000 claims abstract description 7
- 239000011159 matrix material Substances 0.000 claims abstract description 6
- 229910000851 Alloy steel Inorganic materials 0.000 claims abstract description 5
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 5
- 239000010955 niobium Substances 0.000 claims abstract description 5
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 5
- 150000004767 nitrides Chemical class 0.000 claims abstract description 5
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 5
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 5
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000000034 method Methods 0.000 claims description 5
- 238000000889 atomisation Methods 0.000 claims description 3
- 230000000996 additive effect Effects 0.000 claims description 2
- 239000000463 material Substances 0.000 claims 4
- 229910052751 metal Inorganic materials 0.000 abstract description 5
- 239000002184 metal Substances 0.000 abstract description 5
- 238000005056 compaction Methods 0.000 abstract description 3
- 238000007792 addition Methods 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- 238000010791 quenching Methods 0.000 description 2
- 230000000171 quenching effect Effects 0.000 description 2
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000005864 Sulphur Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- CJZGTCYPCWQAJB-UHFFFAOYSA-L calcium stearate Chemical class [Ca+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O CJZGTCYPCWQAJB-UHFFFAOYSA-L 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000004320 controlled atmosphere Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000002939 deleterious effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 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
- C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
- C22C33/0278—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
- C22C33/0292—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5% with more than 5% preformed carbides, nitrides or borides
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Powder Metallurgy (AREA)
Abstract
Steel powder compositions, particularly of tool or alloy steel, for production of metal articles by compaction and sintering contain as additives refractory particles which do not dissolve in a steel matrix and thus serve to maintain a fine grain size. The additives are selected from carbides of niobium, tantalum, titanium and hafnium, the diborides of titanium, zirconium and hafnium and the nitrides of vanadium, titanium, zirconium and hafnium in a quantity of 0.1 to 2.0% by weight.
Description
SPECIFICATION
Powder compositions and production of metal articles therefrom
This invention relates to powder compositions and to the production of metal articles and is particularly concerned with making articles to tool steel and alloy steel from steel in powder or particulate form.
It is well known that metal powders can be compacted in mechanically or isostatically operated presses to form a "green" compact in which the powder particles are locked together and in which the relative density of the compact is low; the "relative density" is the ratio of the actual density of the compact to the density of the solid material from which it is made,expressed as a percentage.
The compact thus contained voids which typically amount to between 20 and 40% of its volume.
After forming the compact it can then be sintered under a controlled atmosphere or a vacuum to produce articles with a relative density of between 90 and 100%.
We have found that, during the sintering step, the sintered articles undergo excessive grain growth and that this has a deleterious effect on the mechanical properties of the sintered articles. This grain growth is caused by the dissolution of the second phase particles in the steel into the steel matrix. For example, in the case of tool steels the carbides normally present in the steel are dissolved in the matrix at the sintering temperature.
These particles normally have the effect of preventing grain growth by stopping the movement of the grain boundaries. A grain boundary which is moving is stopped when it collides with a second phase particle and is then "pinned" by the particle.
We have found that the addition of certain agents will inhibit this grain growth and will thus maintain a fine grain size during the sintering step and will produce superior mechanical properties in the sintered article.
In one aspect the invention provides a steel powder for use in making articles by first compacting the powder to form a relatively loose compact and then sintering the compact to produce an article of at least 90% relative density, which powder contains as additives particles which do not dissolve in the steel matrix and which serve to maintain a fine grain size.
The additives consist of refractory particles and we have found that the additives which can be used in this way are carbides of niobium, tantalum, titanium and hafnium, the diborides of titanium, zirconium and hafnium and the nitrides of vanadium, titanium, zirconium and hafnium in a quantity of 0.1 to 2.0 % by weight
In another aspect the invention provides a method of making an article which comprises making a compact to substantially the required article shape from a steel powder including 0.1 to 2% by weight of one or more of the carbides of niobium, tantalum, titanium and hafnium or the diborides of titanium, zirconium and hafnium or the nitrides of vandaium, titanium, zirconium and hafnium and sintering the compact to make an article of at least 90% relative density.
The invention extends to an article made by the above method or from the above powder; particularly tool or alloy steel. The invention will be more readily understood by the following description of one method of making a tool steel article in accordance therewith, given by way of example only.
The metallic powder was made by taking a melt of tool steel having the following composition besides iron and insignificant impurities:
Carbon 1%
Tungsten 6%
Molybdenum 5%
Chromium 4.5%
Vanadium 2%
Titanium carbide 1%
Manganese less than 0.2%
Sulphur less than 0.03%
Phosphorus less than 0.03%
All percentages being given by weight.
The melt was atomised by jets of water directed at a falling stream of the steel at between 20 and 30 and with a pressure of 1,000 to 4,000 p.s.i. The atomised droplets of water were quenched by contacting with a quenching bath immediately below the point of impact so that the quenching was fast enough to give irregular shaped particles. The quenched droplets fell in the form of powder into the water bath from whic it was removed.
The powder was annealed in a vacuum or hydrogen/nitrogen atmosphere at about 870"C and then subjected to controlled cooling. The annealed powder was blended with graphite and other volatile lubricants such as stearates and/or metallic or other powders in a rotary drum to supply respectively excess carbon for the subsequent deoxidation stage, powder lubrication of pressing, or powders for correction of or addition to the powder composition.
A "green" compact was formed by mechanical or isostatic compaction preferably to 60 to 70% relative density. The compact was then deoxidised and sintered in a vacuum furnace. Preferably the temperature is raised slowly and maintained below the sintering temperature until the oxygen level has been reduced sufficiently and finally the temperature was raised to sintering temperature to produce a compact of at least 90% and preferably greater than 98% relative density.
The addition of the refractory particles (titanium carbide) which did not dissolve in the steel matrix during sintering enabled the maintenance of a fine grain size by pinning the grain boundaries.
The addition may be made in alternative ways:
The elements required may be added to the molten.steel prior to atomisation. For example in the case of carbides they may be added in the form of carbides or simply as metals which due to the stability of the additives discussed above will combine to form the required compounds during the atomisation and will provide a good distribution of fine, stable particles.
Alternatively, the additions may be made in the form of powder by blending the powder additives with the steel powder prior to compaction. The additive particles will then be situated at the boundaries of the steel particles and will also enter the steel particles by diffusion processes to provide a distribution of fine, stable particles throughout the article.
Claims (1)
1. A steel powder for use in making articles by first compacting the powder to form a relatively loose compact and then sintering the compact to produce an article of at least 90% relative density, which powder contains as additives particles which do not dissolve in the steel matrix and which serve to maintain a fine grain size when sintered, in which the additive particles are selected from refractory particles comprising carbides of niobium, tantalum, titanium and hafnium, the diborides of titanium, zirconium and hafnium or the nitrides of vanadium, titanium, zirconium and hafnium in a quantity of 0.1 to 2.0% by weight.
2. A powder according to Claim 1 which is a tool or alloy steel powder.
3. A powder substantially as described herein with reference to the example.
4. A method of making an article which comprises making a compact to substantially the required article shape from a steel powder including 0.1 to 2.0% by weight of material comprising one or more of the carbides of niobium, tantalum, titanium and hafnium, or the diborides of titanium, zirconium and hafnium, or the nitrides of vanadium, titanium, zirconium and hafnium and sintering the compact to make an article of at least 90% relative density.
5. A method according to Claim 4 in which the steel powder is a tool or alloy steel.
6. A method according to Claim 4 or Claim 5 in which the material or additives for forming the material are added to molten steel before atomisation thereof to form a powder.
7. A method according to Claim 4 or Claim 5 in which the material is added as powdered additives and blended with the steel powder.
9. A method of making an article substantially as described herein.
10. An article made from the powder or method of any of the preceding claims.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08425566A GB2165553A (en) | 1984-10-10 | 1984-10-10 | Steel powder compositions and sintered products |
| JP60224982A JPS6196004A (en) | 1984-10-10 | 1985-10-11 | Powder composition and production of metal product therefrom |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08425566A GB2165553A (en) | 1984-10-10 | 1984-10-10 | Steel powder compositions and sintered products |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8425566D0 GB8425566D0 (en) | 1984-11-14 |
| GB2165553A true GB2165553A (en) | 1986-04-16 |
Family
ID=10567967
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08425566A Withdrawn GB2165553A (en) | 1984-10-10 | 1984-10-10 | Steel powder compositions and sintered products |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JPS6196004A (en) |
| GB (1) | GB2165553A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4880461A (en) * | 1985-08-18 | 1989-11-14 | Hitachi Metals, Ltd. | Super hard high-speed tool steel |
| ES2172366A1 (en) * | 1999-07-14 | 2002-09-16 | Tratamientos Termicos Ttt S A | Powder metallurgy based production of high speed steel parts consists of compaction of pre-alloyed powders, for nitriding, and sintering with tempering |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4999050A (en) * | 1988-08-30 | 1991-03-12 | Sutek Corporation | Dispersion strengthened materials |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1114265A (en) * | 1964-06-01 | 1968-05-22 | Du Pont | Refractory dispersions and their production |
| GB1210856A (en) * | 1967-07-31 | 1970-11-04 | Aerojet General Co | Powder metallurgy process |
| GB1414413A (en) * | 1973-05-18 | 1975-11-19 | Contour Saws | Bimetal saw blade stock and method of making the same |
| GB1443900A (en) * | 1973-03-30 | 1976-07-28 | Crucible Inc | Powder metallurgy tool steel article |
| GB1524502A (en) * | 1976-02-05 | 1978-09-13 | Inco Europ Ltd | Dispersion-strengthend ferritic alloy |
| GB2022619A (en) * | 1978-03-21 | 1979-12-19 | Allen Tools Ltd Edgar | High Speed Steels |
-
1984
- 1984-10-10 GB GB08425566A patent/GB2165553A/en not_active Withdrawn
-
1985
- 1985-10-11 JP JP60224982A patent/JPS6196004A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1114265A (en) * | 1964-06-01 | 1968-05-22 | Du Pont | Refractory dispersions and their production |
| GB1210856A (en) * | 1967-07-31 | 1970-11-04 | Aerojet General Co | Powder metallurgy process |
| GB1443900A (en) * | 1973-03-30 | 1976-07-28 | Crucible Inc | Powder metallurgy tool steel article |
| GB1414413A (en) * | 1973-05-18 | 1975-11-19 | Contour Saws | Bimetal saw blade stock and method of making the same |
| GB1524502A (en) * | 1976-02-05 | 1978-09-13 | Inco Europ Ltd | Dispersion-strengthend ferritic alloy |
| GB2022619A (en) * | 1978-03-21 | 1979-12-19 | Allen Tools Ltd Edgar | High Speed Steels |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4880461A (en) * | 1985-08-18 | 1989-11-14 | Hitachi Metals, Ltd. | Super hard high-speed tool steel |
| ES2172366A1 (en) * | 1999-07-14 | 2002-09-16 | Tratamientos Termicos Ttt S A | Powder metallurgy based production of high speed steel parts consists of compaction of pre-alloyed powders, for nitriding, and sintering with tempering |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8425566D0 (en) | 1984-11-14 |
| JPS6196004A (en) | 1986-05-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5108493A (en) | Steel powder admixture having distinct prealloyed powder of iron alloys | |
| US3838981A (en) | Wear-resistant power metallurgy nickel-base alloy | |
| WO1998058093A1 (en) | Stainless steel powder | |
| US6468468B1 (en) | Method for preparation of sintered parts from an aluminum sinter mixture | |
| US5403371A (en) | Iron-based powder, component made thereof, and method of making the component | |
| EP1252274B1 (en) | Lubricant combination and process for the preparation thereof | |
| US5217683A (en) | Steel powder composition | |
| JP6164387B1 (en) | Method for producing alloy steel powder for sintered member raw material | |
| EP1214143B1 (en) | Lubricant composite and process for the preparation thereof | |
| CA2865325C (en) | Improved lubricant system for use in powder metallurgy | |
| JP6409953B2 (en) | Method for producing alloy steel powder for sintered member raw material | |
| EP1513638B1 (en) | Metal powder composition including a bonding lubricant and a bonding lubricant comprising glyceryl stearate. | |
| GB2165553A (en) | Steel powder compositions and sintered products | |
| US4263046A (en) | Sinterable mass for producing workpieces of alloy steel | |
| JP4169369B2 (en) | Agglomerated iron-based powder | |
| EP2571649B1 (en) | Compositions for improved dimensional control in ferrous poweder metallurgy applications | |
| US4286987A (en) | Composition for iron powder compact infiltrant | |
| GB1590953A (en) | Making articles from metallic powder | |
| US3203781A (en) | Method of producing dispersion-hardened metal alloys | |
| US6120575A (en) | Agglomerated iron-based powders | |
| JPH05247608A (en) | Powdery high speed steel | |
| RU2815374C1 (en) | Composite alloy and method of its manufacture | |
| JPS591761B2 (en) | stainless steel powder for powder metallurgy | |
| EP1066128B1 (en) | Metal powders obtained from residue of material removal processes on iron parts produced by chill casting | |
| CN101517110B (en) | Metallurgical powder composition and method of production |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |