US4098623A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for heat treatment of titanium alloy
Assignee: Hitachi Ltd
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Filing: 1976-07-27
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Granted: 1978-07-04
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Expires: 1996-07-27
Abstract
Abstract Titanium alloy or cast titanium alloy is heat-treated in vacuum or a neutral atmosphere to convert the abnormal structure of the alloy to normal α or α + β structure. The titanium alloy or cast titanium alloy thus heat-treated can have sufficiently good material characteristics by the ordinary successive heat treatments.
Inventors
- 👤 Yoshiro Ibaraki
- 👤 Akihiko Yamamoto
- 👤 Toshimi Sasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:22
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/16; C22F1/18; C22F1/183
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
149 words
A method of heat treating a wrought titanium alloy having an abnormal structure that is an α' single phase of the type depicted in FIG. 1a, which comprises: (1) subjecting the wrought titanium alloy, in a neutral atmosphere to from 2 to 10 cycles of heating and cooling, each cycle after the first cycle being in immediate succession to the preceding cycle, the titanium alloy being heated to a temperature ranging from 850° C. to 1000° C. and being cooled to a temperature ranging from room temperature to 600° C. in each cycle, and then; (2) when, at the end of all successive cycles, the temperature of the alloy is above room temperature, cooling the alloy to room temperature, the cycles being selected to yield a normal structure that is an α structure or α + β structure of the type depicted in FIG. 1b having improved material characteristics.
Claim 2
Independent Claim
149 words
A method of heat treating a wrought titanium alloy having an abnormal structure that is an α' single phase of the type depicted in FIG. 1a, which comprises: (1) subjecting the wrought titanium alloy, in a neutral atmosphere to from 2 to 10 cycles of heating and cooling, each cycle after the first cycle being in immediate succession to the preceding cycle, the titanium alloy being heated to a temperature ranging from 850° C. to 1000° C. and being cooled to a temperature ranging from room temperature to 600° C. in each cycle, and then; (2) when, at the end of all successive cycles, the temperature of the alloy is above room temperature, cooling the alloy to room temperature, the cycles being selected to yield a normal structure that is an α structure or α + β structure of the type depicted in FIG. 1b having improved material characteristics.
Claim 3
Dependent Claim
23 words
A method according to claim 1, wherein the neutral atmosphere is an atmosphere selected from the group consisting of vacuum, helium and argon.
Claim 4
Dependent Claim
33 words
A method according to claim 1, wherein wrought titanium alloy is a Ti-6A1-4V alloy and the alloy is heated to about 930° C. and then cooled to about 500° C. during each cycle.
Claim 5
Dependent Claim
14 words
A method according to claim 3, wherein the neutral atmosphere is an argon atmosphere.
Claim 6
Dependent Claim
86 words
A method according to claim 4, wherein the wrought titanium alloy is subjected to three cycles of heating and cooling in which the titanium alloy at room temperature is initially heated to a temperature of 930° C., then cooled to a temperature of 500° C., followed by heating to a temperature of 930° C. and cooling to a temperature of 500° C. and again heating to 930° C. and cooling to room temperature to provide a normal α structure containing a small amount of β structure.
Claim 7
Independent Claim
155 words
A method of heat treating a cast titanium alloy having an abnormal structure that is an acicular α phase of the type depicted in FIG. 2a, which comprises: (1) subjecting the cast titanium alloy, in a neutral atmosphere, to from 2 to 10 cycles of heating and cooling, each cycle after the first cycle being in immediate succession to the preceding cycle, the cast titanium alloy being heated to a temperature ranging from 850° C. to 1000° C. and being cooled to a temperature ranging from room temperature to 600° C. in each cycle, and then; (2) when, at the end of all successive cycles, the temperature of the cast titanium alloy is above room temperature, cooling the cast titanium alloy to room temperature, the cycles being selected to yield a normal structure that is an α structure or an α + β structure of the type depicted in FIG. 2b having improved material characteristics.
Claim 8
Independent Claim
155 words
A method of heat treating a cast titanium alloy having an abnormal structure that is an acicular α phase of the type depicted in FIG. 2a, which comprises: (1) subjecting the cast titanium alloy, in a neutral atmosphere, to from 2 to 10 cycles of heating and cooling, each cycle after the first cycle being in immediate succession to the preceding cycle, the cast titanium alloy being heated to a temperature ranging from 850° C. to 1000° C. and being cooled to a temperature ranging from room temperature to 600° C. in each cycle, and then; (2) when, at the end of all successive cycles, the temperature of the cast titanium alloy is above room temperature, cooling the cast titanium alloy to room temperature, the cycles being selected to yield a normal structure that is an α structure or an α + β structure of the type depicted in FIG. 2b having improved material characteristics.
Claim 9
Dependent Claim
23 words
A method according to claim 6, wherein the neutral atmosphere is an atmosphere selected from the group consisting of vacuum, helium and argon.
Claim 10
Dependent Claim
35 words
A method according to claim 6, wherein the cast titanium alloy is a Ti-6A1-4V alloy and the cast alloy is heated to about 930° C. and then cooled to about 500° C. during each cycle.
Claim 11
Dependent Claim
14 words
A method according to claim 8, wherein the neutral atmosphere is an argon atmosphere.
Claim 12
Dependent Claim
77 words
A method according to claim 9, wherein the cast titanium alloy is subjected to three cycles of heating and cooling in which the alloy at room temperature is heated initially to a temperature of 930° C. and then cooled to 500° C., followed by heating to 930° C. and cooling to 500° C. and again heating to 930° C. and cooling to room temperature to provide a normal α structure containing a small amount of β structure.
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) | 1981-07-03 | 1982-01-02 | 1982-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-03 | 1986-01-02 | 1986-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-03 | 1990-01-02 | 1990-07-04 | $7700.00 | Window Closed / Lapsed |