General Properties
Alloy 600 (UNS designation N06600) is a nickel-chromium
alloy designed for use from cryogenic to elevated
temperatures in the range of 2000°F (1093°C).
Alloy 600 is nonmagnetic and readily weldable.
The alloy is used in a variety of
corrosion resisting applications. The high nickel
content of Alloy 600 provides a level of resistance
to reducing environments, while the chromium content
of the material provides resistance to weaker
oxidizing environments. The high nickel content
of the material provides exceptional resistance
to chloride stress corrosion cracking.
Back to top
Applications
- Chemical and food processing
equipment
- Paper mill and alkaline digesters
- Heat exchangers
- Heat treating mufflers and retorts
Back to top
Standards
| ASTM.......................... |
B 166 |
| ASME.......................... |
SB 166 |
| AMS ........................... |
554 |
| Federal or Military....... |
MIL-N-23226 |
| |
MIL-T-23227 |
Back to top
Corrosion
Resistance
The high nickel content of Alloy 600
provides good resistance to moderate levels of
reducing conditions. The nickel content of the
alloy renders the alloy extremely resistant to
chloride stress corrosion cracking. Alloy 600
is one alloy used in solutions of magnesium chloride.
Similarly, the chromium content of Alloy 600 provides
resistance to weak oxidizing environments. In
this respect, Alloy 600 is an improvement over
Alloy 200 (commercially pure nickel). In strong
oxidizing solutions like hot, concentrated nitric
acid, Alloy 600 has poor resistance. Alloy 600
is relatively unattacked by the majority of neutral
and alkaline salt solutions. It is used in some
caustic environments. Alloy 600 resists steam
and mixtures of steam, air, and carbon dioxide.
The alloy has excellent oxidation resistance to
about 2100°F (1149°C). The nickel content
of the alloy renders it subject to attack at elevated
temperatures in sulfur-containing atmospheres,
however.
Back to top
Chemical
Analysis
Typical Analysis (Weight %)
| C |
Mn |
S |
Si |
Cr |
Ni + Co |
Fe |
Cu |
| 0.05 |
0.25 |
0.002 |
0.20 |
15.5 |
Balance |
8.0 |
0.10 |
Back to top
Mechanical
Properties
Room temperature mechanical properties
of Alloy 600 are shown below. The material is
in the annealed condition.
0.2%
Offeset
Yield Strength |
Ultimate
Tensile Strength |
Elongation |
| psi |
(Mpa) |
psi |
(MPa) |
%
to 2"
(51 mm) |
| 37,000 |
(255) |
93,000 |
(640) |
45 |
Short Time Elevated Temperature
Tensile Properties
The following table illustrates the short time
tensile properties of Alloy 600 at temperatures
above room temperature. Low temperature properties
are added for comparison.
| Test
Temperature |
0.2%
Offset
Yield Strength |
Ultimate
Tensile Strength |
Elongation
Percent
in 2"
(1 mm) |
| °F |
°C |
psi |
(MPa) |
psi |
(MPa) |
| -110 |
(-79) |
42,400 |
(292) |
106,450 |
(734) |
64 |
| 600 |
(316) |
31,000 |
(213) |
90,500 |
(624) |
46 |
| 800 |
(427) |
29,500 |
(203) |
88,500 |
(610) |
49 |
| 1000 |
(538) |
28,500 |
(197) |
84,000 |
(579) |
47 |
| 1200 |
(649) |
26,500 |
(183) |
65,000 |
(448) |
39 |
| 1400 |
(760) |
17,000 |
(117) |
27,500 |
(190) |
46 |
| 1600 |
(871) |
9,000 |
(62) |
15,000 |
(103) |
80 |
| 1800 |
(982) |
4,000 |
(28) |
7,500 |
(52) |
118 |
Back to top
Impact
Resistance
Alloy 600 shows excellent toughness even
at subzero temperatures. The following are typical
results for standard size Charpy V-Notch impact
specimens machined from plate.
| Test
Temperature |
Charpy
Impact Strength, ft-lb (Joules) |
| °F |
°C |
Annealed |
As
Hot Rolled |
Cold
Rolled |
| -100 |
(-73) |
180 |
(244) |
180 |
(244) |
-- |
| 70 |
(21) |
180 |
(244) |
180 |
(244) |
155 |
(156) |
| 1000 |
(538) |
160 |
(217) |
160 |
(217) |
-- |
Back to top
Physical
Properties
Density:
8.42 g/cm3 (0.304 lbs/in3)
Specific Gravity:
8.42
Magnetic Permeability:
I<1.02
Specific Heat:
32-212°F 0.11
Btu/lb-°F
(0-100°C) 460
Joules/kg-°K
Linear Coefficient of Thermal
Expansion
Average
from
|
Linear
Coefficient
of Thermal Expansion
|
| 70°F (21°C) |
to °F (°C) |
10-6
/ °F |
10-6
/ °F |
200
|
(93) |
6.9 |
12.4 |
| 400 |
(204) |
7.3 |
13.1 |
| 600 |
(316) |
7.6 |
13.7 |
| 800 |
(427) |
7.9 |
14.2 |
| 1000 |
(538) |
8.1 |
14.6 |
| 1200 |
(649) |
8.4 |
15.1 |
| 1400 |
(760) |
8.7 |
15.7 |
Thermal Conductivity
| Temperature |
Thermal
Conductivity |
| °F |
(°C) |
Btu-ft / h-ft2 - °F |
W/m - °K |
70
|
21 |
8.6 |
14.8 |
| 200 |
93 |
8.9 |
15.4 |
| 400 |
204 |
9.9 |
17.1 |
| 600 |
316 |
10.8 |
18.7 |
| 8000 |
427 |
11.9 |
20.6 |
| 1000 |
538 |
13.0 |
22.5 |
Elastic Modulus, Modulus of Rigidity,
and Poisson's Ratio
| Temperature |
Elastic
Modulus (E) Units of |
Modulus
of Rigidity (G) Units of |
Poisson's
Ratio |
| °F |
°C |
106 psi GPa |
106 psi GPa |
(µ) |
| 70 |
21 |
30 |
207 |
11 |
76 |
0.29 |
Back to top
Creep
and Stress Rupture Properties
Typical stress rupture properties of
Alloy 600 are presented below in comparison to
some other materials. The data indicate that Alloy
600 has modest load carrying ability in the temperature
range in which creep and stress rupture are design
criteria.
| Temperature |
Stress,
psi (MPa) to Produce Rupture in |
| °F |
°C |
Alloy |
10
hr |
100
hr |
1000
hr |
| |
304 |
— |
43,000 |
(297) |
34,000 |
(234) |
| 1000 |
(538) |
600 |
74,000 |
(510) |
50,000 |
(345) |
34,000 |
(234) |
| |
A-286 |
100,000 |
(690) |
95,000 |
(655) |
88,000 |
(607) |
| |
304 |
— |
23,000 |
(159) |
16,000 |
(110) |
| 1200 |
(649) |
600 |
34,000 |
(234) |
23,000 |
(159) |
14,5000 |
(100) |
| |
800 |
40,000 |
(276) |
32,000 |
(221) |
21,000 |
(145) |
| 1350 |
(732) |
600 |
20,000 |
(138) |
13,500 |
(93) |
9,200 |
(63) |
| |
A-286 |
49,000 |
(338) |
35,000 |
(241) |
21,000 |
(145) |
Back to top
Heat
Treatment
Alloy 600 is not hardenable by heat treatment.
The alloy can only be strengthened by cold working.
Annealing is conducted to soften the material
after cold working operations. Softening begins
at 1600°F (871°C) and can be conducted
to about 2100°F (1149°C). At temperatures
of 1800°F (982°C) or higher, grain growth
will occur rapidly. However, very short time at
1900°F (1038°C) may be used to soften
the material without producing undue grain growth.
Slow cooling or quenching produces approximately
the same hardness in Alloy 600.
Back to top
Processing
Cold Forming
Alloy 600 exhibits the excellent cold forming
characteristics normally associated with chromium-nickel
stainless steels. The high nickel content prevents
the austenite to martensite transformation which
can occur when Alloys 301 or 304 stainless steels
are cold formed. The alloy has a lower work hardening
rate than Alloys 301 or 304 and can be used in
multiple draw forming operations where relatively
large amounts of deformation occur between anneals.
If a high temperature anneal is conducted on the
Alloy 600 to produce a relatively large grain
size for elevated temperature properties, extensive
forming produces a visibly undulated surface called
“orange peel.” This surface characteristic
is produced by the large grain size and is usually
considered detrimental to the properties of the
material.
Back to top
Welding
Alloy 600 can be joined by the standard
resistance and fusion welding processes used for
the stainless steels. A number of welding rods
and wires are commercially available for joining
Alloy 600 to itself and other materials. Since
the alloy forms a tightly adhering oxide, which
can be removed only by grinding, inert gas shielding
is desirable.
Back to top |
