US5129143A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Durable plating for electrical contact terminals
Assignee: TE Connectivity Corp
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Filing: 1990-09-10
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Granted: 1992-07-14
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Expires: 2010-09-10
Abstract
Abstract Electrical contact terminals having two layer plated coating thereon is disclosed. The coating consists of a layer of palladium having a macrostress in the range of 30,000 to 140,000 psi and a layer of gold, the gold being at lest 99.9% pure and having a Knoop hardness from 60 to 90. A coating comprised of medium stress palladium and gold substantially and unexpectedly inmproves the durability of terminals as compared to similar coatings using gold and low or high stress palladium.
Inventors
- 👤 I-Yuan Wei
- 👤 John R. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:10
CPC Classifications
C; C25; C25D; C25D5/00; C25D5/10; H; H01; H01R; H01R13/00; H01R13/02; H01R13/03; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49204; Y10T29/49224
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
143 words
A method for making plated electrical contact terminals for mating with complementary contact members, said terminals having increased durability, the method comprising the steps of: selecting electrical contact terminals; selecting a palladium plating solution and selecting process parameters for plating palladium from a bath of said solution onto electrical contact terminals; plating a layer of palladium from said bath onto said terminal and; plating a layer of gold on said palladium layer having Knoop hardness ranging from 60 to 90; said selecting of said solution and said parameters being optimized so that the palladium layer of terminals plated thereby consistently has a level of internal macrostress of at least 30,000 p.s.i. and up to about 140,000 p.s.i.; whereby the presence of such a substantial macrostress characteristic of the plated palladium layer substantially increases the durability of the contact terminals for long in-service life.
Claim 2
Independent Claim
143 words
A method for making plated electrical contact terminals for mating with complementary contact members, said terminals having increased durability, the method comprising the steps of: selecting electrical contact terminals; selecting a palladium plating solution and selecting process parameters for plating palladium from a bath of said solution onto electrical contact terminals; plating a layer of palladium from said bath onto said terminal and; plating a layer of gold on said palladium layer having Knoop hardness ranging from 60 to 90; said selecting of said solution and said parameters being optimized so that the palladium layer of terminals plated thereby consistently has a level of internal macrostress of at least 30,000 p.s.i. and up to about 140,000 p.s.i.; whereby the presence of such a substantial macrostress characteristic of the plated palladium layer substantially increases the durability of the contact terminals for long in-service life.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein the macrostress of the palladium layer is preferably in the range of 40,000 to 130,000 p.s.i.
Claim 4
Dependent Claim
22 words
The method of claim 1 wherein the palladium layer has a thickness between 5 to 100 microinches, preferably 15 to 80 microinches.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein said gold is at least 99.9 percent pure.
Claim 6
Dependent Claim
23 words
The method of claim 1 wherein the gold layer is within the range of 1 to 7 microinches, preferably 2 to 4 microinches.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-07-14 | 1996-01-13 | 1996-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-14 | 2000-01-13 | 2000-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-14 | 2004-01-13 | 2004-07-14 | $7700.00 | Window Closed / Lapsed |