GB2065710A - Production of high density sintered bodies - Google Patents
Production of high density sintered bodies Download PDFInfo
- Publication number
- GB2065710A GB2065710A GB8037759A GB8037759A GB2065710A GB 2065710 A GB2065710 A GB 2065710A GB 8037759 A GB8037759 A GB 8037759A GB 8037759 A GB8037759 A GB 8037759A GB 2065710 A GB2065710 A GB 2065710A
- Authority
- GB
- United Kingdom
- Prior art keywords
- alloy
- density
- particle size
- microns
- median particle
- 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.)
- Granted
Links
- 238000004519 manufacturing process Methods 0.000 title description 3
- 239000002245 particle Substances 0.000 claims abstract description 64
- 238000000034 method Methods 0.000 claims abstract description 40
- 239000000203 mixture Substances 0.000 claims abstract description 27
- 239000010953 base metal Substances 0.000 claims abstract description 22
- 238000005245 sintering Methods 0.000 claims abstract description 15
- 229910052742 iron Inorganic materials 0.000 claims abstract description 13
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 9
- 239000007791 liquid phase Substances 0.000 claims abstract description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 24
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 14
- 239000010936 titanium Substances 0.000 claims description 13
- 239000000956 alloy Substances 0.000 claims description 10
- 239000011651 chromium Substances 0.000 claims description 10
- 229910045601 alloy Inorganic materials 0.000 claims description 9
- 229910052804 chromium Inorganic materials 0.000 claims description 9
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 8
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 8
- 229910052710 silicon Inorganic materials 0.000 claims description 8
- 239000010703 silicon Substances 0.000 claims description 8
- 229910000756 V alloy Inorganic materials 0.000 claims description 7
- 229910052750 molybdenum Inorganic materials 0.000 claims description 7
- 229910052759 nickel Inorganic materials 0.000 claims description 7
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 4
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 4
- 229910052726 zirconium Inorganic materials 0.000 claims description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 3
- 239000004411 aluminium Substances 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 239000011733 molybdenum Substances 0.000 claims description 3
- 229910052720 vanadium Inorganic materials 0.000 claims description 3
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 claims description 3
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 2
- 229910052721 tungsten Inorganic materials 0.000 claims description 2
- 239000010937 tungsten Substances 0.000 claims description 2
- 229910000838 Al alloy Inorganic materials 0.000 claims 1
- 229910000640 Fe alloy Inorganic materials 0.000 claims 1
- 229910000676 Si alloy Inorganic materials 0.000 claims 1
- 229910001111 Fine metal Inorganic materials 0.000 abstract 1
- 239000002923 metal particle Substances 0.000 abstract 1
- 239000000843 powder Substances 0.000 description 13
- 230000000704 physical effect Effects 0.000 description 6
- 229910052782 aluminium Inorganic materials 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 229910001128 Sn alloy Inorganic materials 0.000 description 2
- -1 aluminium-vanadium-tin Chemical compound 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- YIWGJFPJRAEKMK-UHFFFAOYSA-N 1-(2H-benzotriazol-5-yl)-3-methyl-8-[2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carbonyl]-1,3,8-triazaspiro[4.5]decane-2,4-dione Chemical compound CN1C(=O)N(c2ccc3n[nH]nc3c2)C2(CCN(CC2)C(=O)c2cnc(NCc3cccc(OC(F)(F)F)c3)nc2)C1=O YIWGJFPJRAEKMK-UHFFFAOYSA-N 0.000 description 1
- 229910000519 Ferrosilicon Inorganic materials 0.000 description 1
- 229910017116 Fe—Mo Inorganic materials 0.000 description 1
- NPXOKRUENSOPAO-UHFFFAOYSA-N Raney nickel Chemical compound [Al].[Ni] NPXOKRUENSOPAO-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910001093 Zr alloy Inorganic materials 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000010420 art technique Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 239000012255 powdered metal Substances 0.000 description 1
- 239000011369 resultant mixture Substances 0.000 description 1
- 239000011863 silicon-based powder Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 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
-
- 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
- B22F1/09—Mixtures of metallic powders
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Powder Metallurgy (AREA)
Abstract
Sintered bodies having density approaching the theoretical value are produced in a method which enables the amount of fine metal particles used to be minimised. The method comprises compacting a mixture of base metal particles (e.g. of Fe or Ti) having a median particle size greater than 40 microns and a minor amount of alloy-forming particles having a median particle size not exceeding 20 microns, so as to form a sinterable body of the desired configuration, and sintering the body at a temperature below that at which any liquid phase forms in the body.
Description
SPECIFICATION
Production of high density sintered bodies
The present invention is concerned with powder metallurgy and, more particularly, with the production of high density sintered bodies.
Powder metallurgists have been trying for many years to obtain sintered metal alloy bodies of high density (that is, of low porosity). For example, secondary processing techniques such as hot or cold working and/or hot isostatic pressing have been proposed, but this secondary processing adds significantly to the cost of the resulting body.
It is also known to obtain sintered bodies by sintering at a temperature at which a liquid phase is produced transiently. This method causes problems with reliability, by tending to result in brittle bodies, and it is very important to control the exact sintering temperature, which is difficult to achieve in practice.
A further known method of producing high density sintered bodies, as described in U.S.
Patent 3744993, involves forming the sintered bodies entirely of very fine grain powder. This method has the disadvantage that further processing steps are needed to produce the fine powder and to ensure that all the powder is of the proper size; furthermore, the smaller the particle size of the powder, the greater is its tendency to be pyrophoric.
We have now developed an improved method of producing a high density sintered body, which comprises compacting a mixture of base metal particles having a median particle size greater than 40 microns and a minor amount of alloyforming particles having a median particle size not exceeding 20 microns, so as to form a sinterable body of the desired configuration, and sintering the body at a temperature below that at which any liquid phase forms in the body.
The method according to the invention involves handling only a minor amount of potentially pyrophoric fine powder.
The resulting body has a high density; this density approaches the theoretical density for the material involved. Thus the density of the resulting body is generally at least about 90% of the theoretical density; for an iron-based body the density is preferably at least 93% of the theoretical density while for a titanium-based body the density is preferably at least 97% of the theoretical density.
The resulting body also has physical properties similar to those of a corresponding wrought body.
Typical physical properties of bodies produced according to the present invention using titanium as the base metal are: 135 ksi U.T.S., 125 ksi Y.S., 1 5% elongation, and 27% R.A., as illustrated in
Example 2. (The minimum properties specified for a forged, wrought article, as set forth in
ASTM B348, having a similar chemical composition are as follows: 130 ksi U.T.S., 120 ksi Y.S., 10% elongation, and 25% R.A.).
The alloy-forming particles should be of a metal or alloy which is alloyable with the base metal particles. In addition, it is believed to be desirable that the relative diffusion rates of the alloyforming particles and the base metal particles be of comparable magnitude. For example (particularly when the base metal is titanium), the alloy-forming particles may be of an aluminiumvanadium alloy, an aluminium-vanadium-tin alloy or an aluminium-tin-molybdenum-zirconium alloy, or (particularly when the base metal is iron), the alloy-forming particles may be of silicon, molybdenum, tungsten, chromium, nickel, vanadium or a mixture thereof.
The base metal used in the method according to the invention is preferably chemically pure, that is, it is in the form of the elemental metal or it contains only a minor or trace amount of any alloying element; the base metal is generally commercially pure, of at least 99% purity. The base metal may be titanium or iron, as mentioned above; other suitable base metals include, for example, nickel and zirconium.
Titanium-based bodies produced according to the invention can contain relatively large amounts of oxygen (up to 0.30 to 0.35% by weight) and still have excellent ductility (an elongation of about 12-1 3 percent). This is in contradistinction to cast or wrought articles of a similar chemical composition (having an oxygen content of from about 0.30 to 0.35%) which exhibit limited ductility (an elongation of about 56%). That is, titanium-based bodies produced according to the present invention are strengthened by the presence of relatively high amounts of oxygen, but this does not seriously impair their ductility. Such bodies are superior to those produced by prior art techniques.
As mentioned above, the median particle size of the alloy-forming particles should be 20 microns or less. Such a particle size can be accomplished by a number of well known techniques; for example, such particles can be readily obtained by attriting alloy-forming particles in a commercially available apparatus, such as a Szegvari 1-S attritor, manufactured by Union Process Inc.,
Akron, Ohio. It is preferred to use alloy-forming particles having a median particle size in the range 0.5 to 20 microns, more preferably 2 to 10 microns.
The base metal particles used in the method according to the present invention can be produced by many well known techniques. The median particle size by weight of the base metal particles is greater than 40 microns, preferably not more than 1 77 microns. It is particularly preferred that the median particle size is in the range of from 44 to 105 microns.
The alloy-forming particles and the base metal particles can be mixed together in any conventional manner, for example, by simple mechanical blending, with the alloy-forming particles being present in an amount sufficient to cause satisfactory densification upon sintering.
However, it is essential that the major component of the mixture be base metal particles. If the base metal is titanium, it is preferred that it be present in the mixture in an amount of from 70 to 95% by weight, more preferably 75 to 92% by weight, while if the base metal is iron, it is preferably present in an amount of 70 to 98% by weight, more preferably 85 to 98% by weight.
In mixing the alloy-forming particles and base metal particles, the weight ratio of particles is selected in such a manner that the resultant powder is capable of being formed and then sintered to near theoretical density without the formation of any liquid phase. That is, depending on the specific composition of the alloy-forming particles, various ratios of alloy-forming particles to base metal particles can be utilized. This can be determined empirically having regard to the criteria that (a) the alloy-forming particles have a median particle size by weight of 20 microns or less and (b) that the resulting body be compactible to a degree sufficient to yield upon sintering an article having a density which is near theoretical.
In the compacting stage, both conventional and isostatic moulding techniques have been employed successfully. The green body is preferably compacted to a density of about 65 to 90% of theoretical, more preferably to a density which is 80 to 90% of the theoretical.
In the sintering stage, the exact sintering temperature employed will vary somewhat depending on the composition and amounts of the various components, with the only requirement being that no liquid phase be formed during the sintering procedure.
In order that the present invention may be more fully understood, the following Examples are given by way of illustration only.
In the Examples, the particle sizes given were determined by use of a Coulter counter (Coulter is a Trade Mark); the particle size given is the median particle size by weight determined by the use of this apparatus.
EXAMPLE 1 (Comparative)
Consistent with prior art practice, a 3.7 by 0.58" by 0.60" sintered 90 titanium-6 aluminium-4 vanadium alloy body was produced as follows:
Approximately 10% by weight of a nominal 60 Al/40 V alloy powder, -80 mesh, was blended with 90% by weight -100 mesh Ti. This blend was then compacted at 50 tsi in a rigid mould to a green density of about 8890% of theoretical, and the so-formed body was then vacuum sintered 4 hours at 23000F + 25 to a final density of about 94.596.5% of theoretical. This body had the following physical properties: 11 5 ksi U.T.S., 108 ksi Y.S., 6% elongation, and 9% R.A.
EXAMPLE 2
Two pounds of 60 Al/40 V were put into a
Szegvari S-1 attritor along with about 40 pounds of s111 steel balls and about > gallon of Freon (Freon is a Trade Mark). This A1/V alloy was attrited for 30 minutes, removed from the attritor and dried.
The resultant median particle size was about 3.0 microns. This powder was added to -100 mesh Ti, and processed and sintered as in
Example 1. The resultant sintered density was 99.399.8% of theoretical.
EXAMPLE 3
The procedure of Example 2 was repeated, except that the attrition time was 7 minutes, the resulting median particle size being approximately 10 microns. The resultant sintered density was 99.0% of theoretical.
EXAMPLE 4
The procedure of Example 2 was repeated, except that 8 pounds of powder were attrited to a resultant median particle size of about 6.5 microns. The resultant sintered density was 99.5% of theoretical.
EXAMPLE 5
The procedure of Example 2 was repeated, except that distilled water was used instead of
Freon in the attritor. The resultant sintered density was 99.599.8% of theoretical.
EXAMPLE 6
The procedure of Example 2 was repeated, except that sintering was at 22000F * 300 F, The resultant sintered density was 99.399.4% of theoretical
EXAMPLE 7
The procedure of Example 2 was repeated, except that the compaction pressure was about 30 tsi. The green density was 8384% of theoretical. The sintered density was 99.0-99.1% of theoretical.
EXAMPLE 8
The procedure of Example 2 was repeated, except that Mullite balls were used, with the resultant median particle size being less than 10 microns. The sintered density was 99.5% of theoretical.
EXAMPLE 9
The procedure of Example 2 was repeated, except that -60 + 200 mesh Ti was used. The resultant sintered density was 99.4% of theoretical.
EXAMPLE 10
The procedure of Example 1 was repeated, except that the powder was compacted at 60,000 psi in a flexible mould in an isostatic press to form a 3" diameter billet with a green density of about 8688% of theoretical. After sintering, the billet had a density of 8892% of theoretical.
EXAMPLE 11
The procedure of Example 10 was repeated, except that Al/V powder prepared as in Example 2 was used. The resultant sintered density of the 3" billet was 99.8% of theoretical.
EXAMPLE 12
A mixture of -325 mesh 50 Al/SO V alloy, -325 mesh Sn, and -100 mesh Ti was formed to give an 86 Ti-6 Al-6 V-2 Sn alloy powder. This mixture was processed as in Example 1 with the resultant sintered density being about 96.6% of theoretical. The physical properties of the resulting body were: 131 ksi U.T.S., 113 ksi Y.S., 6% elongation, and 10% R.A.
EXAMPLE 13
An alloy of 42 Al-42 V-1 6 Sn was attrited as described in Example 2. Subsequently, this attrited mixture was mixed with -100 mesh Ti and processed as described in Example 1 to produce an alloy of composition 86 Ti-6 Al-6 V-2 Sn. The resultant sintered density was approximately 99.0% of theoretical. The physical properties of this article were: 1 52 ksi U.T.S., 138 ksi Y.S., 9% elongation and 16.7% R.A.
EXAMPLE 14 (Comparative)
Elemental silicon powder having a median particle size by weight of about 60 microns was blended with atomized iron (-80 mesh Ancosteel 1 000B) so as to obtain a resultant mixture of about 3% by weight silicon, with the remainder being iron. This mixture was formed into the desired configuration and compacted at 50 tsi.
The so-formed body had a green density of 6.6 g/cc. It was then sintered for 2 hours at 21 750F (in hydrogen). The resultant sintered density was 6.94 g/cc, which is about 90.7% of theoretical.
EXAMPLE 1 5 The procedure of Example 14 was repeated, except that the silicon was attrited to a median particle size of 4 microns. The green density of the body was 6.69 g/cc, and the sintered density was 7.4 g/cc, which is 96.7% of theoretical.
EXAMPLE 16
The procedure of Example 15 was repeated, except that sufficient silicon was added to produce a mixture containing 5% silicon. The green density of the body was 6.29 g/cc and the sintered density was 7.17 g/cc, which is 95.0% of theoretical.
EXAMPLE 17
A ferrosilicon alloy (approximately 50% Fe50% Si) was attrited about 30 minutes in Freon to a median particle size, by weight, of about 2 microns. This material was then added to iron (of the type described in Example 14) in an amount sufficient to produce a mixture containing 2% silicon, the balance being iron. The mixture was compacted to a green density of 7.06 g/cc and then sintered for 30 minutes at 20500F in hydrogen. The resultant sintered density was 7.3 g/cc, which is 94.5% of theoretical.
EXAMPLE 18
Elemental molybdenum having a median particle size of 9 microns was mixed with iron (of the type described in Example 14) to produce three Fe-Mo blends containing, respectively, 1, 5 and 10% Mo. After compacting to a green density of 7.25 g/cc, 7.32 g/cc and 7.38 g/cc, respectively, and sintering for 4 hours at 23000F in hydrogen, the Fe-1 % Mo articles exhibited a density of 7.28 g/cc, the Fe-5% Mo article a density of 7.72 g/cc, and the Fe-10% Mo article a density of 7.78 g/cc. These sintered densities are about 92.3,96.8 and 96.3% of theoretical, respectively.
EXAMPLE 19
The procedure of Example 18 was repeated, except that chromium having a median particle size of 5.6 microns was added to iron to produce articles containing Fe-5% Cr, Fe-10% Cr, and Fe 15% Cr. The Fe-5Cr article had a green density of about 7.14 g/cc and a sintered density of about 7.15 g/cc. The Fe-1 0 Cr article had a green density of 6.93 g/cc and a sintered density of 7.38 g/cc. The Fe-15% Cr article had a green density of 6.75 g/cc and a sintered density of 7.30 g/cc. These sintered densities are 91.3, 94.7 and 94.4% of theoretical, respectively.
EXAMPLE 20
The procedure of Example 1 9 was repeated, except that -100 mesh electrolytic chromium was used. The Fe-1 0Cr body had a green density of 6.98 g/cc and a sintered density of 7.1 g/cc.
The Fe-15% Cr had a green density of 6.90 g/cc and a sintered density of 6.96 g/cc. These sintered densities are 91.1 and 89.7% of theoretical, respectively.
EXAMPLE 21
Inco 287 nickel powder (5-10 micron particle size) was blended with iron powder (of the type described in Example 14) to produce a mixture containing 10% Ni. This mixture was compacted to a green density of 7.21 g/cc and then sintered at 23000F for 4 hours in vacuum. The sintered density was 7.49 g/cc, which is 94% of theoretical.
EXAMPLE 22
The procedure of Example 21 was repeated, except that -200 + 325 mesh nickel was used.
The green density was 7.21 g/cc. There was essentially no change in density after sintering.
This sintered density is 90.5% of theoretical.
EXAMPLE 23
A 60 Al/40 V alloy material was attrited for 30 minutes in Freon to a median particle size of 3 microns. This material was then blended with -100 mesh zirconium to produce a mixture containing, by weight, 90% zirconium, 6% aluminium and 4% vanadium which mixture, in turn, was formed into the desired shape and sintered at 22000F for 4 hours under vacuum conditions (better than 1 micron). The green density was 4.58 g/cc with the sintered density being 5.90 g/cc, which is 98.8% of theoretical density.
EXAMPLE 24
Nickel-aluminium (approximately 67% Ni33% Al) was attrited to a median particle size of 3.0 microns. This was added to -80 + 325 mesh nickel powder to produce a mixture containing 95.5 Ni-4.5 Al. The green article formed therefrom had a density of 6.4 g/cc. After sintering at 23000F for 4 hours under vacuum conditions, the resultant article had a density of about 7.1 g/cc.
EXAMPLE 25
The procedure of Example 24 was repeated, except that sufficient aluminium was added to produce a mixture which contained 92.5% Ni and 7.5% Al. The green density was 5.5 g/cc, and the sintered density was 6.5 g/cc.
The benefits of the present invention will be apparent from the foregoing Examples. For example, a conventionally produced powdered metal 90 Ti-6 Al-4 V alloy had a density of 94.596.5% of theoretical (Example 1) whereas an essentially identical 90 Ti-6 Al-4V alloy produced according to the present invention had a density of 99.3-99.8% of theoretical (Example 2). This difference is significant because a body having a density of 99.399.8% of theoretical has chemical and physical properties similar to a wrought alloy of the same composition whereas an article having a density of 94.5-96.5% of theoretical does not.
Claims (10)
1. A method of producing a high density sintered body, which comprises compacting a mixture of base metal particles having a median particle size greater than 40 microns and a minor amount of alloy-forming particles having a median particle size not exceeding 20 microns, so as to form a sinterable body of the desired configuration, and sintering the body at a temperature below that at which any liquid phase forms in the body.
2. A method according to claim 1, in which the base metal is titanium, iron, zirconium, nickel or an alloy thereof.
3. A method according to claim 1 or 2, in which the median particle size of the base metal particles is not more than 177 microns.
4. A method according to any of claims 1 to 3, in which the alloy-forming particles are prealloyed.
5. A method according to claim 4, in which the pre-alloyed particles comprise an alloy of iron and silicon or an alloy of vanadium and aluminium.
6. A method according to any of claims 1 to 3, in which the alloy-forming particles are of silicon, molybdenum, tungsten, chromium, nickel, vanadium or an alloy thereof.
7. A method according to any of claims 1 to 6, in which the median particle size of the alloyforming particles is at leat 0.5 microns.
8. A method according to any of claims 1 to 7, in which the sinterable body has a density of 70 to 90% of the theoretical value.
9. A method of producing a high density sintered body, substantially as described herein in any of Examples 2 to 13 and 15 to 25.
10. A high density sintered body, when produced by a method according to any of claims 1 to 9.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US9750979A | 1979-11-26 | 1979-11-26 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2065710A true GB2065710A (en) | 1981-07-01 |
| GB2065710B GB2065710B (en) | 1984-07-11 |
Family
ID=22263732
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8037759A Expired GB2065710B (en) | 1979-11-26 | 1980-11-25 | Production of high density sintered bodies |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS56123301A (en) |
| AU (1) | AU539115B2 (en) |
| BR (1) | BR8007687A (en) |
| CA (1) | CA1177287A (en) |
| DE (1) | DE3043321A1 (en) |
| FR (1) | FR2469970A1 (en) |
| GB (1) | GB2065710B (en) |
| MX (1) | MX154581A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2181745A (en) * | 1985-08-28 | 1987-04-29 | Avesta Nyby Powder Ab | Hot-deformed powder metallurgy articles |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61246333A (en) * | 1985-04-23 | 1986-11-01 | Honda Motor Co Ltd | Manufacture of high density ti sintered alloy |
| JPH02166201A (en) * | 1988-12-19 | 1990-06-26 | Kobe Steel Ltd | Manufacture of high density sintered body |
| US5167885A (en) * | 1992-01-07 | 1992-12-01 | W. R. Grace & Co.-Conn. | Method for making sintered bodies |
| US5898009A (en) * | 1996-03-19 | 1999-04-27 | Advanced Ceramics Corporation | High density agglomerated boron nitride particles |
| DE69807040T2 (en) * | 1998-02-16 | 2003-05-08 | Advanced Ceramics Corp., Cleveland | Process for forming high density boron nitride and agglomerated high density boron nitride particles |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2805624A (en) * | 1952-03-11 | 1957-09-10 | Olin Mathieson | Metallurgical process |
| US3744993A (en) * | 1970-11-30 | 1973-07-10 | Aerojet General Co | Powder metallurgy process |
| DE2333614A1 (en) * | 1973-07-02 | 1975-02-20 | Olin Corp | Powder metallurgy composite anode matrixes - as multi phase strip from coarse and fine materials |
| SE378260B (en) * | 1973-11-29 | 1975-08-25 | Hoeganaes Ab | |
| SE397780B (en) * | 1976-06-24 | 1977-11-21 | Hoeganaes Ab | KIT FOR PRODUCTION OF SINTER STEEL WITH HIGH STRENGTH AND GOOD DUCTIVITY |
| US4177069A (en) * | 1977-04-09 | 1979-12-04 | Showa Denko K.K. | Process for manufacturing sintered compacts of aluminum-base alloys |
| DE2819091C2 (en) * | 1978-04-29 | 1979-11-15 | Messer Griesheim Gmbh, 6000 Frankfurt | Use of a metal powder mixture |
-
1980
- 1980-11-17 AU AU64445/80A patent/AU539115B2/en not_active Ceased
- 1980-11-17 DE DE19803043321 patent/DE3043321A1/en active Granted
- 1980-11-21 CA CA000365197A patent/CA1177287A/en not_active Expired
- 1980-11-24 FR FR8024864A patent/FR2469970A1/en active Granted
- 1980-11-25 BR BR8007687A patent/BR8007687A/en unknown
- 1980-11-25 GB GB8037759A patent/GB2065710B/en not_active Expired
- 1980-11-26 MX MX184907A patent/MX154581A/en unknown
- 1980-11-26 JP JP16545280A patent/JPS56123301A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2181745A (en) * | 1985-08-28 | 1987-04-29 | Avesta Nyby Powder Ab | Hot-deformed powder metallurgy articles |
| GB2181745B (en) * | 1985-08-28 | 1990-03-21 | Avesta Nyby Powder Ab | A process for the production of powder-metallurgy articles |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56123301A (en) | 1981-09-28 |
| AU6444580A (en) | 1981-06-04 |
| JPH0250172B2 (en) | 1990-11-01 |
| FR2469970A1 (en) | 1981-05-29 |
| CA1177287A (en) | 1984-11-06 |
| BR8007687A (en) | 1981-06-09 |
| MX154581A (en) | 1987-10-07 |
| GB2065710B (en) | 1984-07-11 |
| DE3043321C2 (en) | 1990-10-31 |
| AU539115B2 (en) | 1984-09-13 |
| FR2469970B1 (en) | 1985-01-18 |
| DE3043321A1 (en) | 1981-05-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5482670A (en) | Cemented carbide | |
| US5778301A (en) | Cemented carbide | |
| EP0331679B1 (en) | High density sintered ferrous alloys | |
| US4379719A (en) | Aluminum powder alloy product for high temperature application | |
| KR100236151B1 (en) | Co-Cr-Mo powder metallurgy product and its manufacturing method | |
| US4464199A (en) | Aluminum powder alloy product for high temperature application | |
| US3999952A (en) | Sintered hard alloy of multiple boride containing iron | |
| US4194910A (en) | Sintered P/M products containing pre-alloyed titanium carbide additives | |
| US5098484A (en) | Method for producing very fine microstructures in titanium aluminide alloy powder compacts | |
| EP0217299B1 (en) | Tri-nickel aluminide compositions alloyed to overcome hot-short phenomena | |
| US3215510A (en) | Alloy | |
| US4432795A (en) | Sintered powdered titanium alloy and method of producing same | |
| US4343650A (en) | Metal binder in compaction of metal powders | |
| GB2065710A (en) | Production of high density sintered bodies | |
| EP0171798B1 (en) | High strength material produced by consolidation of rapidly solidified aluminum alloy particulates | |
| EP0200691B1 (en) | Iron-based powder mixture for a sintered alloy | |
| CA1332297C (en) | Nickel-base powder metallurgy alloy | |
| CA1049296A (en) | Powder-metallurgy of cobalt containing brass alloys | |
| US4155754A (en) | Method of producing high density iron-base material | |
| US3451809A (en) | Method of sintering maraging steel with boron additions | |
| WO2020032235A1 (en) | NITRIDE-DISPERSED MOLDED BODY WHICH IS FORMED OF Ni-BASED ALLOY | |
| EP0250414B1 (en) | Method in producing a molding of an iron alloy | |
| JPS62287041A (en) | Production of high-alloy steel sintered material | |
| JPH0751721B2 (en) | Low alloy iron powder for sintering | |
| JPH06271901A (en) | Ti-al intermetallic compound powder having excellent sinterability and sintered compact thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732 | Registration of transactions, instruments or events in the register (sect. 32/1977) | ||
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19951125 |