Alloys or metallic compositions – Nickel base – Copper containing
Reexamination Certificate
1999-12-20
2001-03-27
Jenkins, Daniel J. (Department: 1742)
Alloys or metallic compositions
Nickel base
Copper containing
C420S458000, C148S429000
Reexamination Certificate
active
06207105
ABSTRACT:
BACKGROUND OF THE INVENTION
Animal and vegetable rendering presses and the like include a variety of working parts such as screw flights, breaker bars and pins and metallic screens that are subjected to excessive shear conditions during the kneading and working of the abrasive animal or vegetable medium in the press. In animal rendering operations, the work medium is acidic, and accordingly, the working parts must be capable of enduring in this corrosive environment in addition to fulfilling the requirement of good wear resistance.
In many cases, carbon steel, Ni, Cr and B alloys have been used to make such press parts but, in the long run, these parts exhibit an undesirable brittleness or excessive corrosion that may lead to fracture.
Ni\Cu Monel alloys with minor amounts of Si addition thereto are known as being corrosion resistant in many acidic mediums. However, brittle suicides may be present in these alloys and this leads not only to difficulty in machining of the desired parts but also to the possible fracture failure of the part during prolonged use.
There is accordingly a need in the art for the provision of fracture tough, ductile metallic parts that exhibit high impact strengths so that such parts can be used as working parts in the expression, kneading or shearing of abrasive materials. There is an even more specific need for the provision of such parts that are corrosion resistant in acidic media.
SUMMARY OF THE INVENTION
The present invention is directed to a specialty alloy specifically formulated to produce an as-cast structure comprising a ductile phase and a hard particle phase distributed throughout the ductile phase. The ductile phase is a matrix of gamma phase consisting primarily of nickel and copper. A fine distribution of hard gamma prime phase particles, consisting mainly of titanium aluminum intermetallic, is prevalent throughout the bulk of the material. The alloy is unique, in that it forms the hard particle distribution throughout the bulk of the material and it does this during the slow cooling phase of the casting process. This alloy must cool slowly to adequately form the hard particles. That is why the alloy is so well suited to the casting process, which is a naturally slow cooling process. This combination of structures results in an alloy that has excellent wear resistance, due to the hard particles, and good strength, toughness and ductility due to the ductile matrix. Also, the combination of elements, primarily nickel and copper, gives this alloy superior corrosion resistance.
The invention will be further described in conjunction with the appended drawings and following detailed description.
REFERENCES:
patent: 3282689 (1966-11-01), Santner
patent: 3915760 (1975-10-01), Wenderott
patent: 2345882 (1973-09-01), None
patent: 46-033383 (1971-09-01), None
patent: 52041120 (1975-09-01), None
patent: 53-125219 (1978-11-01), None
patent: 357251 (1972-10-01), None
patent: 483216 (1975-09-01), None
patent: 954476 (1982-08-01), None
ASM Handbook c 1990, vol. 2; pp. 435-436.*
Dean, A.V.; Age hardening in nickel 30% copper alloys containg titanium and aluminum, Jun. 1972 pp. 181-184.
Biebel & French
Coy Nicole
Global Manufacturing Solutions, Inc.
Jenkins Daniel J.
LandOfFree
Wear resistant nickel alloys and methods of making same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Wear resistant nickel alloys and methods of making same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wear resistant nickel alloys and methods of making same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2455820