Claims
- 1. In a method of producing an anti-wear layer on a surface of a structural part of titanium or a titanium alloy including the steps of chemically depositing an adherent layer of nickel on a surface of a structural part of titanium or a titanium alloy, heat treating at a temperature of at least 450.degree. C. the thus coated part to produce diffusion layers of TiNi.sub.3 and Ti.sub.2 Ni between the nickel layer and the titanium part and removing any nickel still present, the improvement comprising galvanically depositing a layer of chromium from a galvanic bath containing CrO.sub.3 onto one of said diffusion layers.
- 2. The improvement as claimed in claim 1, wherein said heat treating is carried out for a period of time of about 16 hours in an oxygen-containing atmosphere.
- 3. The improvement as claimed in claim 1 wherein said galvanic bath comprises, in addition to CrO.sub.3, H.sub.2 SiF.sub.6 and H.sub.2 SO.sub.4.
- 4. The improvement as claimed in claim 1 wherein the galvanic deposition is carried out in the galvanic bath with a current density of 20 to 80 A/dm.sup.2.
- 5. The improvement as claimed in claim 1 wherein said galvanic bath comprises
- 250 grams per liter of said CrO3 ,
- 1.6 grams per liter H.sub.2 SO.sub.4,
- 4 grams per liter H.sub.2 SiF.sub.6,
- said galvanic deposition being carried out at a temperature of 55.degree. C. and a current of 20 to 80 A/dm.sup.2.
- 6. The improvement as claimed in claim 1 wherein the galvanic deposition is effected at a temperature of 50.degree. C. and a current density of 20 to 80 A/dm.sup.2 in the galvanic bath which comprises 265 g/l of said CrO.sub.3 and 1% by weight H.sub.2 SO.sub.4, referred to CrO.sub.3.
- 7. The improvement as claimed in claimed 1 wherein the temperature, time and current density of the galvalic deposit are controlled such that the chromium layer is deposited on the diffusion layer of titanium nickel with a thickness of 50-100 .mu.m.
Priority Claims (1)
Number |
Date |
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Kind |
3716937 |
May 1987 |
DEX |
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Parent Case Info
This is a continuation of copending application Ser. No. 07/195,494 filed on May 18, 1988, now abandoned.
US Referenced Citations (4)
Foreign Referenced Citations (3)
Number |
Date |
Country |
3443329 |
Dec 1983 |
DEX |
244574 |
Apr 1987 |
DEX |
2188942 |
Oct 1987 |
GBX |
Non-Patent Literature Citations (1)
Entry |
F. A. Lowenheim, Electroplating, McGraw-Hill Book Co., New York, 1978, pp. 230-247. |
Continuations (1)
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Number |
Date |
Country |
Parent |
195494 |
May 1988 |
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