Alloys 825

Brand name	Incoloy® 825, Nicrofer 4221

Trade name	Alloy 825

Standards	Material No. 2.4858 EN Designation NiCr21Mo UNS N08825 Alloy 825

Description	Alloy 825 / 2.4858 is a titanium-stabilized nickel-iron-chromium alloy with copper and molybdenum.

Special properties	Good resistance to stress-corrosion cracking. Good resistance to oxidizing and non-oxidizing hot acids.

Chemical Composition	C % ≤ 0.025 Si ≤ % 0.50 Mn ≤ % 1.00 P ≤ % 0.02 S ≤ % 0.015 Cr % 19.5-23.5 Mo % 2.50-3.50 Ni % 38.0-46.0 Ti ≤ % 0.60-1.20 Cu % 1.50-3.00 Al % ≤ 0.20 Co % ≤ 1.00 Fe % Rest

Mechanical Properties 20°C	0.2% Yield strength Rp ≥ N/mm² 240 Tensile strength Rm N/mm² ≥ 550 Elongation A5 ≥ % 30 Modulus of elasticity kN/mm² 195

Physical Properties 20°C	Density g/cm³ 8.1 Specific heat capacity J/kg K 440 Thermal conductivity W/m K 10.8 Electrical resistivity Ω mm²/m 1.12

Suitable welding filler materials	2.4621

Application	Phosphor and sulphur acids plants, oil and gas production

Available forms for 2.4858 / ALLOY 825	Sheets/Plates Bars Wire Tubes/Pipes Fittings Forged / cast parts Finished part (drawing)