38NKD Grade Characteristics
This precision alloy is materials with a minimum thermal coefficient of linear expansion (TKLR 7.0-7.8[1°/C] in the temperature range of -60 +400°C) used for sealed joints with glass grades P-6 and C72-4. Such materials have unique physical and mechanical properties (magnetic, thermal, elastic, electrical) due to the accuracy of composition, thoroughness of manufacturing and processing, absence of unnecessary impurities. This group includes high-alloys based on iron and nickel with additives of cobalt and other elements.
Percentage composition
| Si |
C |
Fe |
Mn |
P |
Ni |
S |
Co |
|---|
| up to 0.4 |
up to 0.3 |
49.72 -53.5 |
37.5 -38.5 |
4.5 -5.5 |
up to 0.015 |
to 0.02 |
4.5 -5.5 |
Physical properties of 38NKD alloy.
| MPa |
Grad |
1/Grad |
J/(kg-grad) |
kg/m3 |
W/(m-grad) |
Ohm-m |
|---|
| E 10- 5 |
T |
a 10 6 |
C |
r |
l |
R 10 9 |
| 1.5 |
20 |
|
|
|
|
500 |
Mechanical properties of 38NKD alloy at 20 °C.
| Product range |
Size |
sT |
sT in |
e.g. |
KCU |
y |
d5 |
Thermal treatment. |
|---|
|
mm |
MPa |
MPa |
- |
kJ/m2 |
% |
% |
- |
|
|
|
450-550 |
|
|
|
23 |
annealing |
Designations
Physical properties of the alloy:
| Description |
Designation |
|---|
| - Alloy data acquisition temperature [degrees] |
- T |
| - Modulus of elasticity of the 1st kind, [MPa] |
- E |
| - Coefficient of thermal linear expansion (at 20°C), [1/Grad] |
-a |
| - Specific electrical resistance [Ohm-m] -R |
-R |
| - Specific gravity [g/cm3] -r |
-r |
| - Heat transfer coefficient [W/(m-grad)] -l |
-l |
| - Specific heat capacity (at 20°C), [J/(kg-grad) |
-C |
Mechanical properties:
| Description |
Designation |
|---|
| - Ultimate yield strength (yield strength for permanent deformation) [MPa] |
sT |
| - Tensile strength [MPa] |
sT |
| - Ratio constriction [ % ] |
y |
| - Tensile elongation [ % ] |
d5 |
| - Brinell hardness, in [MPa] |
HB |
| - Impact toughness [ kJ/m2 ] |
KCU |
Magnetic properties :
| Description |
Designation |
|---|
| - Coercive force (within) [ A/m] |
Hc |
| - Magnetic permeability (not more than) [ MHN/m] |
Umax |
| - Losses (not more than) at frequency 50 Hz and 1.0 Tl [ W/kg ] |
P1.0/50 |
| - Magnetic induction Tl (not less) at magnetic field strength 100, in magnetic fields [ A/m] |
B100 |
| - Coercive force (not less), [ A/m] |
Hc |
| - Magnetic permeability (not more than), [ MHN/m] |
Umax |
| - Losses (not more than) at frequency 50 Hz and 1.0 Tl [ W/kg ] |
P1.0/50 |
weldability:
| Designation |
Description |
|---|
| Limited weldable |
- Must be preheated to 100-120°C with subsequent heat treatment |
| no restrictions |
- No need for preheating and final heat treatment |
| Difficult to weld |
- Preheating to 200-300°C with final heat treatment necessary |
Delivery
All 38NKD grade products are certified. The technical documentation includes data on the chemical composition, the limiting percentage of impurities, and the mechanical properties of products. From us you can buy in bulk a variety of semi-finished products for large-scale production. We also offer good conditions for retail buyers. You will be satisfied with the level of service and efficiency of service.
Buy at a bargain price
Evek GmbH offers its customers an unlimited choice of precision steel of the highest quality at a competitive price. If you can't choose, our experienced managers are always available and ready to consult you. Ordering from us you get certified products that meet international quality standards in the shortest possible time. If you value your time, contact our nearest office today, or order online.
