US4487744A — Corrosion resistant austenitic alloy

Claim 1

Independent Claim 218 words

An austenitic stainless corrosion resistant alloy having good resistance to pitting and crevice corrosion in oxidizing chloride-bearing media combined with resistance to general corrosion and to intergranular corrosion in oxidizing media, said alloy consisting essentially in weight percent of about ______________________________________ w/o ______________________________________ C 0.06 Max. Mn 1.4 Max. Si 0.9 Max. P 0.035 Max. S 0.035 Max. Cr 20-26 Ni 34-44 Mo 3-<5.1 Cu 0.1-<3.1 N 0.4 Max. B 0.005 Max. Ce + La 0.4 Max. Added Nb 1 Max. Ti 0.5 Max. ______________________________________ the amount of nitrogen being not greater than that which can be retained in solution, the amount of cerium plus lanthanum being the amount added, niobium plus titanium when present ranging from a minimum which is sufficient to combine stoichiometrically with the amount of carbon present in excess of 0.025 w/o, the balance being essentially iron, and in which the elements chromium, nickel, molybdenum and copper are balanced so that the value of Correlation I is equal to or less than 1.6021 and the value of Correlation II is equal to or less than 5, Correlation I being defined as 7.0011-0.2269(% Cr)-0.0769(% Ni) -0.046(% Mo)+0.03(% Cu)+0.0017(% Ni) 2 +0.0486(% Mo) 2 -0.0066(% Ni)(% Mo), and Correlation II being defined as 14.7182-0.3759(% Cr)+0.0986(% Ni) -1.2976(% Mo)+0.02(% Cu)-0.0165(% Cr)(% Mo) -0.0202(% Cr)(% Cu)+0.0223(% Ni)(% Cu).

Claim 2

Dependent Claim 218 words

An austenitic stainless corrosion resistant alloy having good resistance to pitting and crevice corrosion in oxidizing chloride-bearing media combined with resistance to general corrosion and to intergranular corrosion in oxidizing media, said alloy consisting essentially in weight percent of about ______________________________________ w/o ______________________________________ C 0.06 Max. Mn 1.4 Max. Si 0.9 Max. P 0.035 Max. S 0.035 Max. Cr 20-26 Ni 34-44 Mo 3-<5.1 Cu 0.1-<3.1 N 0.4 Max. B 0.005 Max. Ce + La 0.4 Max. Added Nb 1 Max. Ti 0.5 Max. ______________________________________ the amount of nitrogen being not greater than that which can be retained in solution, the amount of cerium plus lanthanum being the amount added, niobium plus titanium when present ranging from a minimum which is sufficient to combine stoichiometrically with the amount of carbon present in excess of 0.025 w/o, the balance being essentially iron, and in which the elements chromium, nickel, molybdenum and copper are balanced so that the value of Correlation I is equal to or less than 1.6021 and the value of Correlation II is equal to or less than 5, Correlation I being defined as 7.0011-0.2269(% Cr)-0.0769(% Ni) -0.046(% Mo)+0.03(% Cu)+0.0017(% Ni) 2 +0.0486(% Mo) 2 -0.0066(% Ni)(% Mo), and Correlation II being defined as 14.7182-0.3759(% Cr)+0.0986(% Ni) -1.2976(% Mo)+0.02(% Cu)-0.0165(% Cr)(% Mo) -0.0202(% Cr)(% Cu)+0.0223(% Ni)(% Cu).

Claim 3

Dependent Claim 37 words

The alloy set forth in claim 1 in which carbon is equal to or less than about 0.04 w/o and the amount of niobium plus titanium is such that ##EQU2## is equal to or less than 0.03.

Claim 4

Dependent Claim 42 words

The alloy set forth in claim 1 which contains an amount of niobium plus titanium such that the value of ##EQU3## ranges from about the weight percent of carbon in excess of 0.025 to about the total weight percent of carbon present.

Claim 5

Dependent Claim 39 words

The alloy set forth in claim 1 in which when carbon is greater than 0.03 w/o the minimum amount of niobium plus titanium present is such that ##EQU4## is at least about equal to the weight percent of carbon.

Claim 6

Dependent Claim 16 words

The alloy set forth in claim 1 in which carbon is not more than 0.03 w/o.

Claim 7

Dependent Claim 14 words

The alloy set forth in claim 1 which contains and about 0.4-2 w/o copper.

Claim 8

Dependent Claim 29 words

The alloy set forth in claims 1, 2, 3, 4, 5 or 6 which contains about 0.5 w/o Max. manganese, 0.4 w/o Max. silicon and 0.05 w/o Max. nitrogen.

Claim 9

Dependent Claim 18 words

The alloy set forth in claim 7 which contains about 22.5-24 w/o chromium, and about 37-43 w/o nickel.

Claim 10

Dependent Claim 18 words

The alloy set forth in claim 7 which contains about 22.5-24 w/o chromium, and about 37-41.5 w/o nickel.

Claim 11

Dependent Claim 26 words

The alloy set forth in claim 7 which contains about 22.5-24 w/o chromium, about 37-41.5 w/o nickel, about 3.5-4.5 w/o molybdenum, and about 0.5-1.5 w/o copper.

Claim 12

Dependent Claim 22 words

The alloy set forth in claim 10 which contains about 0.025 Max. phosphorus, about 0.005 Max. sulfur, and about 0.0015-0.0035 w/o boron.

Claim 13

Dependent Claim 19 words

The alloy set forth in claim 1 which contains about 0.025 w/o Max. carbon, and about 0.2-0.3 w/o niobium.

Claim 14

Dependent Claim 47 words

The alloy set forth in claim 1 which contains about 0.023 w/o C, 0.30 w/o Mn, 0.36 w/o Si, 0.024 w/o P, 0.004 w/o S, 23.46 w/o Cr, 37.59 w/o Ni, 3.76 w/o Mo, 1.16 w/o Cu, 0.0017 w/o B, 0.035 w/o N, and 0.27 w/o Nb.

Claim 15

Dependent Claim 215 words

A weld filler material having as-welded good resistance to pitting and crevice corrosion in oxidizing chloride-bearing media combined with resistance to general corrosion and to intergranular corrosion in oxidizing media, consisting essentially in weight percent of about ______________________________________ w/o ______________________________________ C 0.06 Max. Mn 1.4 Max. Si 0.9 Max. P 0.035 Max. S 0.035 Max. Cr 22.5-26 Ni 38-44 Mo 4-<5.1 Cu 0.4-2 N 0.4 Max. B 0.005 Max. Ce + La 0.3 Max. Added Nb 1 Max. Ti 0.5 Max. ______________________________________ the amount of nitrogen being not greater than that which can be retained in solution, the amount of cerium plus lanthanum being the amount added, niobium plus titanium when present ranging from a minimum which is sufficient to combine stoichiometrically with the amount of carbon present in excess of 0.025 w/o, the balance being essentially iron, and in which the elements chromium, nickel, molybdenum and copper are balanced so that the value of Correlation I is equal to or less than 1.6021 and the value of Correlation II is equal to or less than 5, Correlation I being defined as 7.0011-0.2269(% Cr)-0.0769(% Ni) -0.046(% Mo)+0.03(% Cu)+0.0017(% Ni) 2 +0.0486(% Mo) 2 -0.0066(% Ni)(% Mo), and Correlation II being defined as 14.7182-0.3759(% Cr)+0.0986(% Ni) -1.2976(% Mo)+0.02(% Cu)-0.0165(% Cr)(% Mo) -0.0202(% Cr)(% Cu)+0.0223(% Ni)(% Cu).

Claim 16

Dependent Claim 215 words

A weld filler material having as-welded good resistance to pitting and crevice corrosion in oxidizing chloride-bearing media combined with resistance to general corrosion and to intergranular corrosion in oxidizing media, consisting essentially in weight percent of about ______________________________________ w/o ______________________________________ C 0.06 Max. Mn 1.4 Max. Si 0.9 Max. P 0.035 Max. S 0.035 Max. Cr 22.5-26 Ni 38-44 Mo 4-<5.1 Cu 0.4-2 N 0.4 Max. B 0.005 Max. Ce + La 0.3 Max. Added Nb 1 Max. Ti 0.5 Max. ______________________________________ the amount of nitrogen being not greater than that which can be retained in solution, the amount of cerium plus lanthanum being the amount added, niobium plus titanium when present ranging from a minimum which is sufficient to combine stoichiometrically with the amount of carbon present in excess of 0.025 w/o, the balance being essentially iron, and in which the elements chromium, nickel, molybdenum and copper are balanced so that the value of Correlation I is equal to or less than 1.6021 and the value of Correlation II is equal to or less than 5, Correlation I being defined as 7.0011-0.2269(% Cr)-0.0769(% Ni) -0.046(% Mo)+0.03(% Cu)+0.0017(% Ni) 2 +0.0486(% Mo) 2 -0.0066(% Ni)(% Mo), and Correlation II being defined as 14.7182-0.3759(% Cr)+0.0986(% Ni) -1.2976(% Mo)+0.02(% Cu)-0.0165(% Cr)(% Mo) -0.0202(% Cr)(% Cu)+0.0223(% Ni)(% Cu).

Claim 17

Dependent Claim 24 words

The weld filler material set forth in claim 14 which contains about ______________________________________ w/o ______________________________________ Cr 22.5-24 Ni 41.5-43 Mo 4.5-<5.1 Cu 0.5-2 ______________________________________

Claim 18

Dependent Claim 33 words

The weld filler material set forth in claim 15 which contains ______________________________________ w/o ______________________________________ C 0.015 Max Mn 0.5 Max Si 0.20 Max. P 0.020 Max. S 0.005 Max. Nb 0.3 Max ______________________________________

Claim 19

Dependent Claim 23 words

The weld filler material set forth in claims 15 and 16 which contains about 0.05 w/o Max. nitrogen, and about 0.0015-0.0035 w/o boron.

Claim 20

Dependent Claim 232 words

A welded austenitic stainless corrosion resistant article at least the welded portion of which is made of an alloy having as-welded good resistance to pitting and crevice corrosion in oxidizing chloride-bearing media combined with resistance to general corrosion and to intergranular corrosion in oxidizing media, said alloy consisting essentially in weight percent of about ______________________________________ w/o ______________________________________ C 0.06 Max. Mn 1.4 Max. Si 0.9 Max. P 0.035 Max. S 0.035 Max. Cr 22.5-26 Ni 38-44 Mo 4-<5.1 Cu 0.4-2 N 0.4 Max. B 0.005 Max. Ce + La 0.3 Max. Added Nb 1 Max. Ti 0.5 Max. ______________________________________ the amount of nitrogen being not greater than that which can be retained in solution, the amount of cerium plus lanthanum being the amount added, niobium plus titanium when present ranging from a minimum which is sufficient to combine stoichiometrically with the amount of carbon present in excess of 0.025 w/o, the balance being essentially iron, and in which the elements chromium, nickel, molybdenum and copper are balanced so that the value of Correlation I is equal to or less than 1.6021 and the value of Correlation II is equal to or less than 5, Correlation I being defined as 7.0011-0.2269(% Cr)-0.0769(% Ni) -0.046(% Mo)+0.03(% Cu)+0.0017(% Ni) 2 +0.0486(% Mo) 2 -0.0066(% Ni)(% Mo), and Correlation II being defined as 14.7182-0.3759(% Cr)+0.0986(% Ni) -1.2976(% Mo)+0.02(% Cu)-0.0165(% Cr)(% Mo) -0.0202(% Cr)(% Cu)+0.0223(% Ni)(% Cu).

Claim 21

Dependent Claim 232 words

A welded austenitic stainless corrosion resistant article at least the welded portion of which is made of an alloy having as-welded good resistance to pitting and crevice corrosion in oxidizing chloride-bearing media combined with resistance to general corrosion and to intergranular corrosion in oxidizing media, said alloy consisting essentially in weight percent of about ______________________________________ w/o ______________________________________ C 0.06 Max. Mn 1.4 Max. Si 0.9 Max. P 0.035 Max. S 0.035 Max. Cr 22.5-26 Ni 38-44 Mo 4-<5.1 Cu 0.4-2 N 0.4 Max. B 0.005 Max. Ce + La 0.3 Max. Added Nb 1 Max. Ti 0.5 Max. ______________________________________ the amount of nitrogen being not greater than that which can be retained in solution, the amount of cerium plus lanthanum being the amount added, niobium plus titanium when present ranging from a minimum which is sufficient to combine stoichiometrically with the amount of carbon present in excess of 0.025 w/o, the balance being essentially iron, and in which the elements chromium, nickel, molybdenum and copper are balanced so that the value of Correlation I is equal to or less than 1.6021 and the value of Correlation II is equal to or less than 5, Correlation I being defined as 7.0011-0.2269(% Cr)-0.0769(% Ni) -0.046(% Mo)+0.03(% Cu)+0.0017(% Ni) 2 +0.0486(% Mo) 2 -0.0066(% Ni)(% Mo), and Correlation II being defined as 14.7182-0.3759(% Cr)+0.0986(% Ni) -1.2976(% Mo)+0.02(% Cu)-0.0165(% Cr)(% Mo) -0.0202(% Cr)(% Cu)+0.0223(% Ni)(% Cu).

Claim 22

Dependent Claim 27 words

The welded article as set forth in claim 18 in which said alloy contains about ______________________________________ w/o ______________________________________ Cr 22.5-24 Ni 41.5-43 Mo 4.5-<5.1 Cu 0.5-2. ______________________________________

Claim 23

Dependent Claim 36 words

The welded article set forth in claim 19 made from an alloy which contains ______________________________________ w/o ______________________________________ C 0.015 Max Mn 0.5 Max Si 0.20 Max. P 0.020 Max. S 0.005 Max. Nb 0.3 Max ______________________________________

Claim 24

Dependent Claim 24 words

The welded article set forth in claim 19 made from an alloy which contains about 0.05 w/o Max. nitrogen, and about 0.0015-0.0035 w/o boron.

Claim 25

Dependent Claim 24 words

The welded article set forth in claim 20 made from an alloy which contains about 0.05 w/o Max. nitrogen, and about 0.0015-0.0035 w/o boron.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1987-12-11	1988-06-11	1988-12-11	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1991-12-11	1992-06-11	1992-12-11	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1995-12-11	1996-06-11	1996-12-11	$7700.00	Window Closed / Lapsed

Corrosion resistant austenitic alloy

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