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EP0158271A2
Expired / Lapsed
EP
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Process for ion nitriding aluminum or aluminum alloys
Assignee: Toyota Central R&D Labs Inc
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Filing: 1985-04-02
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Granted: —
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Expires: 2005-04-02
Abstract
Abstract A process for ion nitriding aluminium or an aluminium alloy as an article to be treated, in which: the article is disposed in a sealed vessel; the oxygen gas in the vessel is removed; the surface of the article is heated to a prescribed nitriding temperature; the surface of the article is activated to facilitate the formation of an aluminium nitride layer by the subsequent nitriding treatment; and thereafter the article is subjected to ion nitriding, thereby forming an aluminium nitride layer having excellent wear resistance and high hardness. This ion nitriding treatment for aluminium material can be carried out even at temperatures lower than a solution treatment temperature of aluminium material.
Inventors
- 👤 Hideo Tachikawa
- 👤 Takatoshi Suzuki
- 👤 Hironori Fujita
- 👤 Tohru Arai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 05:04
CPC Classifications
C; C23; C23C; C23C8/00; C23C8/06; C23C8/36
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
110 words
A process for ion nitriding aluminum or aluminum alloy as an article to be treated, comprising the steps of disposing said article to be treated in a sealed vessel; removing the residual oxygen gas in said vessel; heating the surface of said article to a prescribed nitriding temperature by introducing a heating gas into said vessel and causing discharge therein; activating the surface of said article by introducing an activating gas into said vessel and causing discharge therein; and ion nitriding the surface of said article by introducing a nitriding gas into said vessel and causing discharge therein, thereby forming an aluminum nitride layer having high hardness and wear resistance.
Claim 2
Dependent Claim
110 words
A process for ion nitriding aluminum or aluminum alloy as an article to be treated, comprising the steps of disposing said article to be treated in a sealed vessel; removing the residual oxygen gas in said vessel; heating the surface of said article to a prescribed nitriding temperature by introducing a heating gas into said vessel and causing discharge therein; activating the surface of said article by introducing an activating gas into said vessel and causing discharge therein; and ion nitriding the surface of said article by introducing a nitriding gas into said vessel and causing discharge therein, thereby forming an aluminum nitride layer having high hardness and wear resistance.
Claim 3
Dependent Claim
29 words
A process according to Claim 1, wherein said activating gas is at least one rare gas selected from the group consisting of helium, neon, argon, kripton, xenon and radon.
Claim 4
Dependent Claim
28 words
A process according to Claim 2, wherein said discharge in the activating step is one of direct current glow discharge, alternating current glow discharge and ion beam sputtering.
Claim 5
Dependent Claim
33 words
A process according to Claim 3, wherein the pressure in said vessel in the activating step is in the range of from 10- 3 to 5 Torr (1.33·10 -6 to 6.67·10 -3 bar).
Claim 6
Dependent Claim
25 words
A process according to Claim 2, wherein said nitriding gas is selected from nitrogen gas, ammonia gas and a mixed gas of nitrogen and hydrogen.
Claim 7
Dependent Claim
26 words
A process according to Claim 5, wherein said discharge in the ion nitriding step is one of direct current glow discharge and alternating current glow discharge.
Claim 8
Dependent Claim
34 words
A process according to Claim 6, wherein the pressure in said vessel in the ion nitriding step is in the range of from 10- 1 to 20 Torr (1.33·10 -4 to 2.67·10 -2 bar).
Claim 9
Dependent Claim
22 words
A process according to Claim 1, wherein the ion nitriding step is carried out at a temperature ranging from 300 to 550°C.
Claim 10
Dependent Claim
55 words
A process according to Claim 1, wherein said residual oxygen gas is removed by repeating a series of the reduction of pressure in said vessel and the subsequent replacement of the residual oxygen gas by a gas introduced therein, and said ion nitriding step is carried out at a temperature ranging from 300 to 550°C.
Claim 11
Dependent Claim
34 words
A process according to Claim 9, wherein said reduction of pressure is carried out by a vacuum pump selected from a rotary pump and a combination of a rotary pump and a diffusion pump.
Claim 12
Dependent Claim
38 words
A process according to Claim 10, wherein said introduced gas in the removing step is one of hydrogen gas and a rare gas,.and said ion nitriding step is carried out at a temperature ranging from 300 to 550°C.
Claim 13
Dependent Claim
41 words
A process according to Claim 2, wherein said heating gas in the heating step is selected from hydrogen gas, nitrogen gas and a rare gas, and said ion nitriding step is carried out at a temperature ranging from 300 to 550°C.
Claim 14
Dependent Claim
25 words
A process according to Claim 13, wherein said discharge in the heating step is one of direct current glow discharge and alternating current glow discharge.
References Cited (Backward Citations)
No citation records indexed.
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