US4034906A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diffusion bonding utilizing eutectic fugitive liquid phase
Assignee: RTX Corp
•
Filing: 1975-02-13
•
Granted: 1977-07-12
•
Expires: 1995-02-13
Abstract
Abstract Members comprised of materials such as titanium and zirconium and their alloys are bonded together in a non-reacting environment with the aid of foil-type braze alloy preforms. The preforms are positioned between the members to be joined, pressure is applied and the joint assembly is subjected to a temperature in excess of 1550° F but below the beta transus of the members. The preforms are fabricated from a titanium-zirconium foil to which a eutectic depressant alloying agent has been added. The depressant forms, with the titanium and zirconium, a low melting point eutectic which, with extended isothermal heating, will diffuse into the base materials.
Inventors
- 👤 Carl E. Carlson
- 👤 Eugene J. Delgrosso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:18
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; B23K35/32; B23K35/325; B23K35/001; B23K35/005; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12222; Y10T428/12493; Y10T428/12771; Y10T428/12806
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
165 words
A method of braze bonding metal surfaces selected from the group consisting of Ti, Zr and alloys thereof comprising the steps of: placing a foil preform between a pair of said surfaces to be joined to define a joint assembly, the preform consisting essentially of a Ti-(50 + 6)Zr alloy foil having a thin eutectic depressant alloying agent layer on at least one side of said foil; applying pressure across the joint comprising the surfaces to be joined with the foil preform sandwiched therebetween; placing the assembly including the preform in a non-reacting atmosphere; heating the assembly to a temperature in the range of 1625° F ± 75° F whereby the depressant will form a low melting point eutectic with the titanium and zirconium, the eutectic melting and filling the gaps between the surfaces to be joined; continuing the application of heat to promote interdiffusion of the alloying agents and solidification at temperature; and cooling the joint assembly after the desired interdiffusion has been achieved.
Claim 2
Independent Claim
165 words
A method of braze bonding metal surfaces selected from the group consisting of Ti, Zr and alloys thereof comprising the steps of: placing a foil preform between a pair of said surfaces to be joined to define a joint assembly, the preform consisting essentially of a Ti-(50 + 6)Zr alloy foil having a thin eutectic depressant alloying agent layer on at least one side of said foil; applying pressure across the joint comprising the surfaces to be joined with the foil preform sandwiched therebetween; placing the assembly including the preform in a non-reacting atmosphere; heating the assembly to a temperature in the range of 1625° F ± 75° F whereby the depressant will form a low melting point eutectic with the titanium and zirconium, the eutectic melting and filling the gaps between the surfaces to be joined; continuing the application of heat to promote interdiffusion of the alloying agents and solidification at temperature; and cooling the joint assembly after the desired interdiffusion has been achieved.
Claim 3
Dependent Claim
52 words
The method of claim 1 wherein the step of placing the foil preform between the surfaces to be joined comprises: selecting said titanium-zirconium alloy foil; coating said titanium-zirconium foil on at least a first side with said eutectic depressant alloying agent; and positioning the coated foil between the surfaces to be joined.
Claim 4
Dependent Claim
26 words
The method of claim 2 wherein the step of coating the foil comprises: applying the depressant to the foil by means of sputtering in a vacuum.
Claim 5
Dependent Claim
23 words
The method of claim 3 wherein the step of sputtering includes: forming a thin layer of beryllium on both sides of the foil.
Claim 6
Dependent Claim
34 words
The method of claim 2 wherein the step of applying pressure comprises: compressing the foil between the surfaces to be joined by the application of pressure in the range of 2 to 100 psi.
Claim 7
Dependent Claim
34 words
The method of claim 1 wherein the step of applying pressure comprises: compressing the foil between the surfaces to be joined by the application of pressure in the range of 2 to 100 psi.
Claim 8
Dependent Claim
34 words
The method of claim 1 wherein said preform consists essentially of a Ti-(50 ± 6)Zr alloy foil approximately 4-5 mils thick having a layer of Be approximately 0.1-0.2 mil thick on each side thereof.
References Cited (Backward Citations)
US3188732A
Cited
US3038249A
Cited
US3451792A
Cited
US3561099A
Cited
US3666429A
Cited
US3675311A
Cited
US3854194A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-11 | 1981-01-10 | 1981-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-11 | 1985-01-10 | 1985-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-11 | 1989-01-10 | 1989-07-12 | $7700.00 | Window Closed / Lapsed |