DESCRIPTION
ХН78Т – a special heat-resistant alloy based on nickel and chromium is designed for continuous operation at temperatures up to 1100 °C. It has such properties as excellent resistance to oxidizing environments at temperatures up to 1100 °C, good mechanical properties at temperatures up to 1000 °C, resistance to the formation of oxide on the surface at temperatures up to 1000 °C, good metallurgical stability. It is melted in open electric furnaces and by using different types of melting.
Main application ХН78Т – unloaded or low-loaded details operating in corrosive gas environments with temperatures of 550-1100 °C (II group); loaded details with 100-1000 hours of work at temperatures up to 1000 °C (III group). For example: flame tube, combustion chamber, flues, covers for thermocouples, etc.
CHEMICAL COMPOSITION
Nom. composition |
С |
Si |
Mn |
S |
P |
Сr |
Ni |
Fe |
Ti |
Al |
Min |
– |
– |
– |
– |
– |
19.00 |
Rest |
– |
0.15 |
– |
Max |
0.12 |
0.80 |
0.70 |
0.010 |
0.015 |
22.00 |
1.00 |
0.35 |
0.15 |
PHYSICAL PROPERTIES
Temperature |
20°С |
100°С |
200°С |
300°С |
400°С |
500°С |
600°С |
700°С |
800°С |
900°С |
Coefficient of elasticity, 10-5 MPа |
2.24 |
2.19 |
2.13 |
2.06 |
2.00 |
1.93 |
1.84 |
– |
– |
– |
Coefficient of linear expansion, ? x 10-6/К |
– |
12.20 |
13.00 |
13.40 |
13.80 |
14.10 |
14.70 |
15.40 |
15.50 |
– |
Thermal conductivity, W/mK |
– |
14.60 |
16.70 |
18.50 |
20.60 |
22.70 |
24.80 |
26.80 |
28.90 |
– |
Resistance, ? mm2/m |
1.09 |
1.099 |
1.108 |
1.117 |
1.127 |
1.153 |
1.135 |
1.126 |
1.123 |
– |
MECHANICAL PROPERTIES
Tensile strength, sв |
Yield strength, sT |
Elongation, d5 |
Contraction ratio, y |
Hardness |
N/mm2 (kgf/mm2) |
N/mm2 (kgf/mm2) |
% |
% |
НВ |
> 700 (71) |
>300 (40) |
>30 |
>50 |
<230.00 |
PRODUCT RANGE
Finish |
Diameter, mm |
Standard (chemical composition) |
Standard (product range) |
Hot rolled |
8.00 – 75.00 |
ГОСТ 5632-72 |
ГОСТ 2590-2006; ГОСТ 2590-88; ГОСТ 5949-75; ГОСТ 2591-88; ТУ 14-1-1671-76 |
Forgings |
75.00 – 350.00 |
ГОСТ 5632-72 |
ГОСТ 25054-81; ТУ 14-1-1530-75; ТУ 14-1-1531-75; ТУ1 4-1-2902-80 |
ANALOGUES
W.N |
EN |
International name |
UNS |
2.4951 |
NiCr20Ti |
Alloy 75 |
N06075 |