OhmAlloy109
(
Common Name:
Ni80Cr20,Nikrothal 8,MWS-650,NiCrA,Tophet A,HAI-NiCr 80,Chromel A,Alloy A,Alloy 650,N8,Resistohm 80, Stablohm 650,Nichorme V,Nikrothal 80.)
Nichrome has a
silvery gray
coloration. Nichrome wires are quite
oxidation resistant
. When at a high temperature environment, up to 1200 C (Nicr 8020), both nickle oxide and chromium oxide will be formed. As chromium oxide is more stable than nickel oxide, a layer of chromium oxide will be formed on the surface of the nichrome wire. The diffusion rate D of oxygen through chromium oxide is very low, which is 10-14 cm2/sec.
In order to have enough resistance, mental conduct wires always are designed into thin form. They process of oxidation will be quick, making them brittle and break when heated in air. By contrast, not only does nichrome have a excellent oxidation resistant, it also has a good
ductility after high temperature use
. Besides that, nichrome alloys have a
higher emissivity
compared to other air-stable resistance alloys. Nichrome alloys will endure a lower element temperature at the same surface load. Moreover, Nichrome alloys will be preferred in low-temperature applications because of its
non-magnetic
feature. It also has a
higher hot and creep strength,
wet corrosion resistance
and
good wear resistance.
A marked increase in electrical resistivity is observed with increasing chromium additions. An addition level of 20% chromium is considered the optimum for electrical resistance wires suitable for heating elements. This composition combines good electrical properties with good strength and ductility, making it suitable for wire drawing.
Application Examples
Nichrome is used to prepare bridgewire for
electric ignition systems
like model rocket igniters, electric matches and electronic cigarettes.
Nichrome wires are used to test the flame color in the non-illuminated parts of cation fire from the cations of sodium, copper, potassium and calcium.
Nichrome is also used in microbiological laboratories.
This substance is used in the manufacturing of
motorcycle silencers
.
Normal composition
%
|
C
|
P
|
S
|
Mn
|
Si
|
Cr
|
Ni
|
Al
|
Fe
|
Other
|
|
Max
|
|
0.0
3
|
0.02
|
0.015
|
0.60
|
0.75~1.60
|
2
0
.0~
23
.0
|
Bal.
|
Max 0.50
|
Max 1.0
|
-
|
Typical Mechanical properties(1.0mm)
|
Yield strength
|
Tensile Strength
|
Elongation
|
|
Mpa
|
Mpa
|
%
|
|
420
|
810
|
30
|
Typical Physical properties
|
Density
(
g/cm3
)
|
8.
4
|
|
Electrical resis
t
ivity at 20ºC
(Ω
mm2/m
)
|
1.09
|
|
Conductivity coefficient at 20ºC (WmK)
|
15
|
|
Coefficient of thermal expansion
|
|
Temperature
|
Coefficient of
Thermal Expansion x10-6/
ºC
|
|
20 ºC-
1000
ºC
|
1
8
|
|
Specific heat capacity
|
|
Temperature
|
20ºC
|
|
J/gK
|
0.46
|
|
Melting point
(
ºC
)
|
1
400
|
|
Max continuous operating temperature in air
(
ºC
)
|
1200
|
|
Magnetic properties
|
non-magnetic
|
|
Temperature Factors Of Electrical Resistivity
|
|
20ºC
|
100ºC
|
200ºC
|
300ºC
|
400ºC
|
600ºC
|
|
1
|
1.00
6
|
1.01
2
|
1.0
18
|
1.0
25
|
1.0
18
|
|
700ºC
|
800ºC
|
900ºC
|
1000ºC
|
1100ºC
|
1300ºC
|
|
1.0
1
|
1.0
08
|
1.0
1
|
1.0
14
|
1.0
21
|
-
|
Style of supply
|
Alloys
Name
|
Type
|
Dimension
|
|
OhmAlloy109
W
|
Wire
|
D
=0.03mm~8mm
|
|
OhmAlloy109
R
|
Ribbon
|
W=
0.4~40
|
T=
0.03~2.9mm
|
|
OhmAlloy109
S
|
Strip
|
W=
8~250mm
|
T=
0.1~3.0
|
|
OhmAlloy109
F
|
Foil
|
W=
6~120mm
|
T=
0.003~0.1
|
|
OhmAlloy109
B
|
Bar
|
Dia=
8~100mm
|
L=
50~1000
|