Powder metallurgy processes – Powder metallurgy processes with heating or sintering – Making composite or hollow article
Patent
1996-12-04
1998-09-29
Jenkins, Daniel J.
Powder metallurgy processes
Powder metallurgy processes with heating or sintering
Making composite or hollow article
419 6, 419 8, 419 23, 419 26, 419 28, 419 49, B22F 704
Patent
active
058157905
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention concerns a method relating to the manufacturing of a composite metal product. More particularly, the invention concerns a method for the manufacturing of a composite article consisting of at least two stainless steel materials having different chemical compositions, particularly a composite stainless article on which a decorative pattern may or has been produced by etching.
BACKGROUND OF THE INVENTION
A number of conventional techniques exist for bounding together metal alloys to achieve composite products. Among these techniques, in the first place forge welding should be mentioned, wherein two or more heated blanks are welded together through forging or hot rolling. This technique is widely used for the manufacturing of compound steel wherein e.g. an unalloyed or a low-alloyed construction steel is bounded to a stainless steel for the production of a composite product. As far as composite products consisting of two or more stainless steels having different chemical compositions are concerned, the possibility to use forge welding, however, is limited because it from technical reasons is difficult to bound stainless steels of different types together through forge welding, for example martensitic and austenitic stainless steels.
Old sword-blades and knife-blades from iron age and medieval time sometimes exhibit decorative patterns having varying chemical composition within a single piece of iron. Artifacts from oldest times exhibit patterns obtained as a result of the metallurgical processes used at that time. So called wootz forgings have patterns which are achieved through slow cooling of hypereutectic carbon steels; other types are the result of a technique in which liquid steel droplets having different chemical compositions are caused to solidify to form a forging blank. Later the smiths learned how to bound steel pieces in form of layers having different chemical compositions by forge welding so that patterns of high artistic quality could be produced through etching subsequent to plastic working and kneading. Such articles, usually referred to as damascened (Damascus) forgings dominating the weapon industry from early medieval time to Viking time, basically because these compound materials could combine a tough blade with a hard, wear resistant edge material. Still the forge welding technique is used for the production of exclusive knife-blades and sword-blades, but only such steel types can be used which have a sufficient hot workability and which can be bonded together by forge welding. This means that it has not been possible to manufacture stainless knife- or sword-blades having damascened patterns through classic or conventional technique. Instead the choice of material has been restricted to low alloyed materials, possibly with the addition of phosphorus or nickel for the achievement of a sufficient contrast after etching.
BRIEF DISCLOSURE OF THE INVENTION
It is the purpose of the invention to suggest a method for the manufacturing of a composite metal product, which has not the above mentioned restrictions. The invention is based on the concept that at least one of the stainless steel materials consists of powder and that the two stainless steel materials are bonded to form a consolidated body through hot isostatic compaction, so called HIP-ing, at a pressure exceeding 600 bar and a temperature exceeding 1000.degree. C.. Suitably a powder is used which is produced through so called atomizing, which means that a stream of molten metal is disintegrated to droplets by means of an inert gas, whereafter the droplets are caused to solidify to form a powder in the inert gas. Thereafter the powder is sieved to a particle size of max. 1 mm The HIP-ing can be performed through conventional hot isostatic pressing, wherein the different materials which shall be bonded to each other, at least one of said materials consisting of a powder, is placed in a closed capsule, from which the air is evacuated, whereafter the capsule is subjected to the hot isostatic pressing. Th
REFERENCES:
patent: 3280614 (1966-10-01), Cordray et al.
patent: 3753704 (1973-08-01), Manilla et al.
patent: 3778875 (1973-12-01), Morabito
patent: 4050143 (1977-09-01), Aslund
patent: 4065302 (1977-12-01), Turillon
patent: 4259413 (1981-03-01), Taglag et al.
patent: 4261745 (1981-04-01), Watanabe et al.
patent: 4399611 (1983-08-01), Maringer
patent: 4581202 (1986-04-01), Kudo et al.
patent: 4581300 (1986-04-01), Hoppin, III et al.
patent: 4601878 (1986-07-01), Aslund et al.
patent: 4602952 (1986-07-01), Greene et al.
patent: 4606884 (1986-08-01), Gavinet et al.
patent: 4844863 (1989-07-01), Miyasaka et al.
patent: 4881430 (1989-11-01), Hubbard
patent: 4966748 (1990-10-01), Miyasaka et al.
patent: 5069886 (1991-12-01), Ekbom
patent: 5350637 (1994-09-01), Ketcham et al.
Patent Abstracts of Japan, vol. 7, No. 1, M-183, Abstract of JP, A, 57-161004 Guroorii K.K.), Oct. 4, 1982, see also the patent doc. especially the figures.
Industrial Heating, Jan. 1981, C. Aslund et al. "Extrusion and Hot Isostatic Pressing of Parts from Stainless Steel and Nickel Base Powders".
Billgren Per
Embretsen Kaj
Bednarek Michael D.
Jenkins Daniel J.
Soderfors Powder Aktiebolag
LandOfFree
Method relating to the manufacturing of a composite metal produc does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method relating to the manufacturing of a composite metal produc, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method relating to the manufacturing of a composite metal produc will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-697207