INCONEL 617 TECHNICAL DATA


Type Analysis | Description | Application | Physical Properties
Mechanical Properties | Corrosion Resistance | Machineability

Type Analysis

Element

Min

Max

Carbon

0.05

0.15

Nickel

Remainder

Iron

--

3.00

Silicon

--

0.50

Manganese

--

0.50

Cobalt

10.0

15.0

Chromium

20.0

24.0

Titanium

--

0.60

Phosphorus

--

0.015

Sulfur

--

0.015

Molybdenum

8.00

10.0

Aluminum

0.80

1.50

Boron

--

0.006

Copper

--

0.50

Description

Alloy 617 is a solid-solution, nickel-chromium-cobalt-molydenum alloy with an exceptional combination of high-temperature strength and oxidation resistance. The alloy also has excellent resistance to a wide range of corrosive environment, and it is readily formed and welded by conventional techniques.
The high nickel and chromium contents make the alloy resistant to a variety of both reducing and oxidizing media. The aluminum, in conjunction with the chromium, provides oxidation resistance at high temperatures. Solid-solution strengthening is imparted by the cobalt and molydenum.


Application

The combination of high strength and oxidation resistance at temperatures over 1800°F makes alloy 617 an attractive material for such components as ducting, combustion cans, and transition liner in both aircraft, and land based gas turbines. Because of its resistance to high-temperature corrosion, the alloy is used for catalyst-grid supports in the production of nitric acid, for heat-treating baskets, and for reduction boats in the refining of molybdenum. Alloy 617 also offers attractive properties for components of power-generating plants, both fossil-fueled and nuclear.


Physical Properties

The alloy's low density, compared with tungsten-containing alloys of similar strength, is significant in applications such as aircraft gas turbines where high strength-to-weight ratio is desirable.

Density, lb/cu in............................................... 0.302
              kg/cu m................................................ 8360
Melting Range, °F.................................... 2430/2510
                         °C................................... 1332-1377
Specific heat at 78°F (26°C)
                         Btu/lb-°F.... ............................. 0.100
                         J/kg-°C........................................ 419
Electrical Resistivity at 78°F (26°C)
                          ohm-cir mil/ft............................. 736
                          æê-m........................................ 1.223

Electrical and Thermal Properties

Temperature

Electrical
Resistivity

Thermal
Conductiviy*

Coefficient
of Expansion**

Specific Heat***

°F

ohm-circ mil/ft

Btu - in/ft² - hr - °F

10(-6)in./in./°F

Btu/lb-°F

78
200
400
600
800
1000
1200
1400
1600
1800
2000

736
748
757
764
770
779
793
807
803
824
--

94
101
113
125
137
149
161
173
185
197
209

--
6.4
7.0
7.4
7.6
7.7
8.0
8.4
8.7
9.0
9.2

0.100
0.104
0.111
0.117
0.124
0.131
0.137
0.144
0.150
0.157
0.163

°C

æê-m

W/m-°C

æm/m/°C

J/kg-°C

20
100
200
400
600
800
1000

1.222
1.245
1.258
1.278
1.308
1.342
1.378

13.4
14.7
16.3
19.3
22.5
25.5
28.7

--
11.6
12.6
13.6
14.0
15.4
16.3

419
440
465
515
561
611
662

*Calculated from electrical resistivity.
**Mean coefficient of linear expansion between 78°F and temperature shown.
***Calculated values.

Modulus of Elasticity*

Temperature

Tensile
Modulus

Shear
Modulus

Poisson's
Ratio**

°F(°C)

10(6)psi(GPa)

10(6)psi(GPa)

74(25)
200(100)
400(200)
600(300)
800(400)
1000(500)
1200(600)
1400(700)
1600(800)

30.6(211)
30.0(206)
29.0(201)
28.0(194)
26.9(188)
25.8(181)
24.6(173)
23.3(166)
21.9(149)

11.8(81)
11.6(80)
11.2(77)
10.8(75)
10.4(72)
9.9(70)
9.5(66)
9.0(64)
8.4(61)

0.30
0.30
0.30
0.30
0.30
0.30
0.30
0.30
0.30

*Determined by dynamic method
**Calculated from moduli of elasticity


Mechanical Properties

Product
Form

Production
Method

Yield Strength (0.2% Offset)

Tensile Strength

Elongation,
%

Reduction
of Area,
%

Hardness
BHN

1000 psi

MPa

1000 psi

MPa

Plate
Bar
Tubing
Sheet or Strip

Hot Rolling
Hot Rolling
Cold Drawing
Cold Rolling

46.7
46.1
55.6
50.9

322
318
383
351

106.5
111.5
110.0
109.5

734
769
758
755

62
56
56
58

56
50
--
--

172
181
193
173

Stability of Properties
Alloy 617 exhibits unusually good metallurgical stability for an alloy of its strength level.Studies involving exposure of material to temperatures of 1100°F to 1400°F showed that although the alloy experiences increases in strength and decreased in ductility it forms no embrittling phases. The table below shows changes in tensile and impact properties after exposures extending to 12,000 hours at elevated temperatures. All samples were in the solution-annealed condition before exposure. The strengthening is attributable to carbide formation and, at exposure temperatures of 1200°F to 1400°F, to precipitation of gamma prime phase.

Exposure
Temperature

Exposure
Time,
h

Yield Strength (0.2% Offset)

Tensile Strength

Elongation,
%

Impact
Strength

°F

°C

1000 psi

MPa

1000 psi

MPa

ft-lb

J

No Exposure

--

46.3

319

111.5

769

68

171

232

1100

595

100
1000
4000
8000
12000

46.5
51.8
55.7
59.5
67.6

321
357
384
410
466

111.5
116.5
117.5
121.5
132.0

769
803
810
838
910

69
67
67
61
34

213
223
181
98
69

289
302
245
133
94

1200

650

100
1000
3640
8000
12000

51.8
66.6
76.3
76.5
77.5

357
459
526
527
534

114.5
133.5
142.0
144.0
144.0

789
920
979
993
993

69
37
33
28
32

191
35
35
40
38

259
47
47
54
52

1300

705

100
1000
4000

58.7
70.5
70.6

405
486
487

126.5
138.0
138.0

872
952
952

38
33
36

57
48
48

77
65
65

1400

760

100
1000
4000
8000
12000

58.3
56.3
58.1
58.5
56.4

402
388
401
403
389

126.5
126.0
128.5
130.0
129.5

872
879
886
896
893

35
37
38
40
38

56
63
62
64
67

76
85
84
87
91


Corrosion Resistance

The composition of alloy 617 includes substantial amounts of nickel, chromium, and aluminum for a high degree of resistance to oxidation and carburization at high temperatures. Those elements, along with the molybdenum content, also enable the alloy to withstand many wet corrosive environments.

Oxidation and Carburization
The excellent resistance of alloy 617 to oxidation results from the alloy's chromium and aluminum contents. At elevated temperatures, those elements cause the formation of a thin, subsurface zone of oxide particles. The zone forms rapidly upon exposure to high temperatures until it reaches a thickness of 0.001 to 0.002 in. The oxide zone provides the proper diffusion conditions for the formation of a protective chromium oxide layer on the surface of the metal. It also helps to prevent spalling of the protective layer. Alloy 617 has excellent resistance to carburization. The table below shows the superiority of alloy 617 over alloys of similar strength in a gas-carburization test at 1800°F. The weight-gain measurements indicate the amount of carbon absorbed during the test period.

Results of 100-h Carburization Tests in Hydrogen/2% Methane at 1800°F (980°C)

Material

Weight Gain, g/m²

Alloy 617
Alloy 263
Alloy 188
Alloy L-605

35
82
86
138

Corrosion by Acids
Alloy 617 has good resistance to a variety of both reducing and oxidizing acids. The chromium in the alloy confers resistance to oxidizing solutions while the nickel and molybdenum provide resistance to reducing conditions. The molybdenum also contributes resistance to crevice corrosion and pitting.
In boiling nitric acid, at concentrations under 20%, corrosion rates are less than 1mpy (0.025mm/yr). At 70% concentration, the rate is a relatively low 20mpy (0.5 mm/yr). The rates were determined from tests of 72 hrs duration.
In sulfuric acid, alloy 617 has shown useful resistance to concentrations of up to about 30% at a temperature of 175°F and about 10% at boiling temperature. The table below gives the results of laboratory tests in sulfuric acid. Test duration was 72 hrs except for tests in boilng 30% and 40% solutions, which were of 48 hrs duration.
The alloy has shown moderate to poor resistance to hydrochloric acid. Laboratory tests at 175°F have produced corrosion rates of 150 mpy (3.8 mm/yr) at 10% concentration, 95 mpy (2.4 mm/yr) at 20% concentration, and 50 mpy (1.3 mm/yr) at 30% concentration.
Alloy 617 has excellent resistance to phosphoric acid. The table below also gives rates for phosphoric acid containing 1% of hydrofluoric acid. Test duration was 72 hrs. In hydrofluoric acid, alloy 617 exhibits useful resistance to the vapor phase at concentrations up to about 20%. The alloy has poor resistance to the liquid acid.

Corrosion Rates in Sulfuric Acid

Acid
Concentration
%

Corrosion Rate*

175°F (80°C)

Boiling
Temperature

mpy

mm/yr

mpy

mm/yr

5
10
20
30
40
50

--
2
32
44
40
94

--
0.05
0.81
1.12
1.02
2.39

24
28
97
464
838
--

0.61
0.71
2.46
11.89
21.29
--

*Average of two tests.

Corrosion Rates in Phosphoric Acid

Acid
Concentration
%

Corrosion Rate*

H3PO4,
175°F (80°C)

H3PO4,
Boiling

H3PO4+ 1% HF
175°F (80°C)

mpy

mm/yr

mpy

mm/yr

mpy

mm/yr

10
20
30
40
50
60
70
85

0.2
0.2
0.4
0.4
0.7
0.4
0.4
0.6

0.005
0.005
0.010
0.010
0.018
0.010
0.010
0.015

0.1
0.4
0.5
5
31
50
38
26

0.003
0.010
0.013
0.13
0.79
1.27
0.97
0.66

0.9
2
1
6
8
6
0.6
0.4

0.023
0.05
0.03
0.15
0.20
0.15
0.015
0.010

*Average of two tests.

Corrosion Rates in Hydrofluoric Acid at 175°F

Acid
Concentration
%

Corrosion Rate*

Vapor Phase

Liquid Phase

mpy

mm/yr

mpy

mm/yr

10
20
30
40
48

44
32
82
85
104

1.12
0.81
2.08
2.16
2.64

126
302
396
424
428

3.20
7.67
10.06
10.77
10.87

*Average of two tests.


Machinability

Alloy 617 has good fabricability. Forming, machining, and welding are carried out by standard procedures for nickel alloys. Techniques and equipment for some operations may be influenced by the alloy's strength and work-hardening rate.

Hot and Cold Forming
Alloy 617 has good hot formability, but it requires relatively high forces because of its inherent strength at elevated temperatures. In general, the hot-forming characteristics of alloy 617 are similar to those of Inconel alloy 625. The temperature range for heavy forming or forging is 1850 to 2200°F . Light working can be done at temperatures down to 1700°F.
Alloy 617 is readily cold formed by conventional procedures although its work-hardening rate is high. For best results , the alloy should be cold formed in the fine-grain condition, and frequent intermediate anneals should be used. Annealing for cold forming should be done at 1900°F.

Heat Treatment
Alloy 617 is normally used in the solution-annealed condition. That condition provides a coarse grain structure for the best creep-rupture strength. It also provides the best bend ductility at room temperature. Solution annealing is performed at a temperature of 2150°F for a time commensurate with section size. Cooling should be by water quenching or rapid air cooling.

Joining
Alloy 617 has excellent weldability. Inconel Filler Metal 617 is used for gas-tungsten-arc and gas-metal-arc welding. The composition of the filler metal matches that of the base metal, and deposited weld metal is comparable to the wrought alloy in strength and corrosion resistance. The table below lists typical room temperature tensile properties of all-weld-metal specimens from welded joints.

Room-Temperature Tensile Properties in As-Welded Condition of Joints Welded with Inconel Filler Metal 617

Specimen

Yield Strength
(0.2% Offset)

Tensile Strength

Elongation
%

Reduction
of Area
%

1000 psi

MPa

1000 psi

MPa

All-Weld-Metal*
All-Weld-Metal**

73.9
78.6

510
542

110.4
119.3

761
823

43.3
37.3

42.0
38.3

*Gas-metal-arc process. Average of ten tests.
**Gas-tungsten-arc process. Average of seventeen tests.

Inconel 617 - Current Inventory Stock

All Trademarks and/or Trade names are the properties of their respective owners