When extreme temperatures and demanding conditions push your materials to their absolute limit, GX40CrNiSi25-20 (1.4848, comparable in analysis to 1.4845) is the answer. This highly heat-resistant, austenitic stainless steel with a high chromium, nickel and silicon content offers an outstanding combination of oxidation resistance, strength and creep resistance at temperatures of up to 1,200°C. It is ideal for use in high-temperature environments, such as industrial furnaces, heat exchangers or thermocouple protection tubes, where other materials would fail.
Material GX40CrNiSi25-20 (1.4848 / 1.4845)
Specialised for the highest temperatures and aggressive media
Material designations and standards
Material number:
1.4848 / 1.4845
Standard designation (EN):
GX40CrNiSi25-20
Standards:
EN 10295 (Heat-resistant cast steels)
AISI/SAE:
–
Similar materials:
1.4823 (GX15CrNiSi25-20, lower strength, better corrosion resistance)
Specifications and details
The benefits of GX40CrNiSi25-20 (1.4848 / 1.4845)
Areas of application
GX40CrNiSi25-20 properties at a glance
Special feature
The steel is specially designed for extremely high temperatures and is resistant to oxidation and scaling.
Versatility
The material is resistant to many corrosive media, especially at high temperatures.
Resistance
GX40CrNiSi25-20 retains its strength even at high temperatures and can therefore bear loads even under the influence of heat.
Chemical composition and mechanical properties.
C (Kohlenstoff):
≤ 0,40 %
Si (Silizium):
1,50 - 2,50 %
Mn (Mangan):
≤ 1,50 %
P (Phosphor):
≤ 0,04 %
S (Schwefel):
≤ 0,03 %
Cr (Chrom):
24,0 - 26,0 %
Ni (Nickel):
19,0 - 22,0 %
Tensile strength (Rm):
≥ 600 MPa
Yield strength (Rp0.2):
≥ 300 MPa
Elongation at break (A5):
≥ 15 %
Hardness (HB):
≤ 250 HB
Solution annealing:
1050 - 1150 °C, followed by slow cooling to reduce stress
Stress relief annealing:
200 - 300 °C to minimise internal stresses
Oxidation resistance:
Very good due to the high silicon content, even at fluctuating temperatures and in oxidising atmospheres
Why GX40CrNiSi25-20?
Cost-effectiveness
Thanks to their very high load-bearing capacity, components made from GX40CrNiSi25-20 have a very long service life and reduced maintenance costs.
Processing
The steel casts well and is weldable under certain conditions.
Areas of use
The material is used, for example, for furnace components, annealing boxes, muffles, heat shields and combustion chamber parts.