Apparatus for surface hardening of refractory metal workpieces

Metallurgical apparatus – Means for treating ores or for extracting metals – By means applying heat to work – e.g. – furnace

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266252, 148276, 148630, C22B 110

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active

053240090

ABSTRACT:
A process and apparatus for forming a hardened outer shell (40) on a refractory metal workpiece (36) preferably heated in a fluidized bed of metallic oxide particles (38) in an environment of an inert gas and a reactive gas with the reactive gas either oxygen or nitrogen. The workpieces (36) are heated in the fluidized bed to a temperature between 800 F. and 1600 F. for a period of over two hours to form hardened outer shell (40) in two layers (42, 44). Outer layer (42) is an oxide or nitride layer having a thickness (T1) between 10 microns and 25 microns. Inner layer (44) is a case hardened layer of the refractory metal having a thickness (T2) between 25 microns and 75 microns. In one embodiment workpieces (56) may be cold worked by peening from finely divided metal oxide particles (54) to provide a uniform surface texture for subsequent hardening.

REFERENCES:
patent: 2987352 (1961-06-01), Watson
patent: 3053704 (1962-09-01), Munday
patent: 3197328 (1965-07-01), Jung et al.
patent: 3369598 (1968-02-01), List
patent: 3401923 (1968-09-01), Bearce
patent: 3408236 (1968-10-01), Van Hartesvelot
patent: 3492740 (1970-02-01), Geipel et al.
patent: 3615885 (1971-10-01), Watson et al.
patent: 3630501 (1971-12-01), Shabaker
patent: 4141759 (1979-02-01), Pfistermeister et al.
patent: 4154574 (1979-05-01), Keirle et al.
patent: 4193758 (1980-03-01), Peterson et al.
patent: 4474553 (1984-10-01), Takahashi
patent: 4478648 (1984-10-01), Zeilinger et al.
patent: 4547228 (1984-10-01), Girrell et al.
patent: 4623400 (1986-11-01), Japka et al.
patent: 4637837 (1987-01-01), Von Matuschka et al.
patent: 4671824 (1987-06-01), Haygarth
patent: 4853024 (1989-08-01), Song
"Corrosion of Zirconium and Zircaloy-2", L. Anderson et al., Electrochemical Technology, vol. 4, No. 3-4, pp. 157-162 Dec. 1966.
Paper Entitled "Improved Wear Resistance of Zirconium By Enhanced Oxide Films" By John C. Haygarth & Lloyd J. Fenwick Presented Apr. 9-13, 1984.
Brochure of Teledyne Wah Chang-Albany, Summer Aug. 1990, Article By Willard E. Kemp Entitled "Nobelizing: Creating Tough, wear resistant surfaces on zirconium", pp. 4, 5, and 8.

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