Nichroma®70

GENERAL INFORMATION

Alloys for heaters make special group of alloys which differ in combination of heat resistance and high electric resistance. It is necessary to admit such combination as rare, because achievement of each of specified properties separately is a difficult task.

Heat resistance is the most important parameter, which is predetermining service durability of heaters. More strict requirements are imposed on heat resistance of alloys for heaters, than to structural steels and alloys, namely, it is necessary more high working temperature – up to 1400оС.

SPECIALTY OF NICHROME

Nichrome – generalizing name of a class of the nickel-based alloys intended for manufacture of resistors and heating elements.

The manufacturing techniques of a cold-drawn nichrome wire of grade Nichroma® provide uniform structure, uniformity of a protective oxidic layer and its high durability. The high plasticity of a wire, lack of tendency to intercrystallite high-temperature corrosion, a high limit of creep resistance, and also stability against oxidation, sulfidization and carburizing at the increased temperatures are guaranteed because of lowered content of carbon.

Nichromes Nichroma ®80Н, Nichroma ®80, Nichroma ®70, Nichroma ®60 and Nichroma ®30 have high specific electric resistance and are used in electroheating furnaces for all industries, in furnaces for annealing and drying, in household appliances and thermal action devices.

Alloy Nichroma®70 is widely used in electric furnaces, furnaces for annealing and drying, various electric devices of thermal action and for production of heat resisting conveyor grids. Maximal work temperature - 1200оС.

Alloy is used for maintenance of maximal temperatures, with cyclic heating and cooling.

Classification

DIN

2.4872 (NiCr20AlSi)

UNS

N06008

Chemical composition, %

Ni

Cr

C

Mn

Si

rest

29.0-31.0

≤0.07

≤1.0

1.0-1.5

Fe

Cu

Al

REE

≤1.0

≤0.5

≤0.2

0.01-0.04

Mechanical properties at 20°С

Diameter, mm

Elongation, %, not less

0,12 – 0,5

18

0,5 – 1,00

18

1,0 – 12,0

25

CREEP CHARACTERISTICS

Temperature, оС

Creep resistance, 10-6

600

80

800

15

1000

4

1200

0.5

PHYSICAL PROPERTIES

Temperature, оС

Resistance μΩm

Exten. 10-6

20

1,19

-

200

1,22

13,5

400

1,24

14,5

500

1,25

14,8

600

1,24

15,0

800

1,24

16,0

1000

1,24

17,0

1200

1,25

-