Iron-nickel alloy
Disclosed is a creep-resistant low-expansion iron-nickel alloy that is provided with increased mechanical resistance and contains 40 to 43 wt. % of Ni, a maximum of 0.1 wt. % of C, 2.0 to 3.5 wt. % of Ti, 0.1 to 1.5 wt. % of Al, 0.1 to 1.0 wt. % of Nb, 0.005 to 0.8 wt. % of Mn, 0.005 to 0.6 wt. % of Si, a maximum of 0.5 wt. % of Co, the remainder being composed of Fe and production-related impurities. Said alloy has a mean coefficient of thermal expansion <5×10<−6>/K in the temperature range of 20 to 200 DEG C.
1. A method comprising fabricating a mold from materials comprising a creep-resistant and low-expansion iron-nickel alloy that has increased mechanical strength and producing an aircraft part of carbon fiber-reinforced composite in the mold, the alloy consisting essentially of, in % by weight,
Ni
37.0 to 40.5%
C
max. 0.1%
Ti
2.0 to 3.0%
Al
0.1 to 0.8%
Nb
0.1 to 0.6%
Mn
0.005 to 0.1%
Si
0.005 to 0.1%
Co
>3.5 and <5.5
remainder Fe and impurities,
the alloy satisfying the condition Ni+½ Co>38 and <43%;
the alloy having a mean thermal expansion coefficient of <3.5×10 −6 /K in a temperature range from 20 to 200° C., the alloy being solution annealed and cured to have a yield point of R p0.2 ≧871 MPa-≦0.950 MPa and a tensile strength R m ≧1060 MPa-≦1179 MPa.
2. The method in accordance with claim 1 , wherein the alloy from which the mold is fabricated comprises sheet material, strip material, or tube material.
3. The method in accordance with claim 1 , wherein the alloy from which the mold is fabricated comprises wire and the fabricating of the mold comprises welding with the wire comprised of the alloy.
4. The method in accordance with claim 1 , wherein only parts of the mold that are subject to mechanical loads higher than those to which other parts of the mold are subject are fabricated from the alloy.
5. The method in accordance with claim 1 , wherein the alloy from which the mold is fabricated is in the form of forged stock.
6. The method in accordance with claim 1 , wherein the alloy from which the mold is fabricated is in the form of cast stock.
7. The method in accordance with claim 1 , the alloy consisting essentially of, in % by weight,
Ni
38.0 to 39.5%
C
0.001 to 0.05%
Ti
2.0 to 3.0%
Al
0.1 to 0.7%
Nb
0.1 to 0.6%
Mn
0.005 to 0.1%
Si
0.005 to 0.1%
Co
>4.0 and <5.5%
remainder Fe and impurities, the alloy satisfying the condition Ni+½ Co>38.5 and <43%.
8. A method comprising fabricating a mold from materials comprising a creep-resistant and low-expansion iron-nickel alloy that has increased mechanical strength and producing an object of carbon fiber-reinforced composite in the mold, the alloy consisting essentially of, in % by weight,
Ni
37 to 41%
C
max. 0.1%
Ti
2.0 to 3.5%
Al
0.1 to 1.5%
Nb
0.1 to 1.0%
Mn
0.005 to 0.8%
Si
0.005 to 0.6%
Co
2.5 to 5.5%
remainder Fe and impurities,
the alloy satisfying the following condition:
Ni+½ Co>38 to <43.5%, the alloy having a mean thermal expansion coefficient of <4×10 −6 /K in a temperature range from 20 to 200° C.
9. The method in accordance with claim 1 or 8 , wherein the alloy further comprises, in % by weight,
Cr
max. 0.1%
Mo
max. 0.1%
Cu
max. 0.1%
Mg
max. 0.005%
B
max. 0.005%
N
max. 0.006%
O
max. 0.003%
S
max. 0.005%
P
max. 0.008%
Ca
max. 0.005%.
10. The method in accordance with claim 8 , the alloy consisting essentially of, in % by weight,
Ni
37.5 to 40.5%
C
max. 0.1%
Ti
2.0 to 3.0%
Al
0.1 to 0.8%
Nb
0.1 to 0.6%
Mn
0.005 to 0.1%
Si
0.005 to 0.1%
Co
>3.5 to <5.5%
remainder Fe and impurities, the alloy satisfying the condition Ni+½Co>38 and <43%,
and has a mean thermal expansion coefficient of <3.5×10 −6 /K in a temperature range from 20 to 200° C.
11. The method in accordance with claim 10 , the alloy consisting essentially of, in % by weight,
Ni
38.0 to 39.5%
C
0.001 to 0.05%
Ti
2.0 to 3.0%
Al
0.1 to 0.7%
Nb
0.1 to 0.6%
Mn
0.005 to 0.1%
Si
0.005 to 0.1%
Co
>4.0 to <5.5%
remainder Fe and impurities, the alloy satisfying the condition Ni+½ Co>38.5 and <43%.
12. The method in accordance with claim 10 or 11 , wherein the alloy is provided with the following maximum contents of the following elements, in % by weight,
Cr
max. 0.1%
Mo
max. 0.1%
Cu
max. 0.1%
Mg
max. 0.005%
B
max. 0.005%
N
max. 0.006%
O
max. 0.003%
S
max. 0.005%
P
max. 0.008%
Ca
max. 0.005%.
13. A method comprising fabricating a mold from materials comprising a creep-resistant and low-expansion iron-nickel alloy that has increased mechanical strength and producing an object of carbon fiber-reinforced composite in the mold, the alloy consisting essentially of, in % by weight,
Ni
38.0 to 39.0%
C
0.001 to 0.02%
Ti
2.0 to 2.5%
Al
0.1 to 0.45%
Nb
0.1 to 0.45%
Mn
0.005 to 0.05%
Si
0.005 to 0.5%
Co
>4.0 to <5.5%
remainder Fe and impurities, the alloy satisfying the condition
Ni+½ Co>40.0 and <42.0%, and has a mean thermal expansion coefficient of <3.2×10 −6 /K in a temperature range from 20 to 200° C.
14. The method in accordance with claim 13 , wherein said mean thermal expansion coefficient is <3.0×10 −6 /K.