25-6Mo 1.4529 UNS
N08926
Introduction: This
is one of four similar specifications for 6%Mo superaustenitics X NiCrMoCuN
25 20 6 (1.4529), UNS NO8367, UNS NO8925 and UNS NO8926. Each has controlled compositions
with nominally 21%Cr 25%Ni 6.5%Mo 0.2%N with some variations (notably Cu and N)
between specifications. Compared with common austenitic steels, they are considerably
strengthened by the nitrogen addition, and their higher nickel content provides
good resistance to chloride stress-corrosion cracking plus less potential to form
deleterious phases, eg. sigma. Good resistance to pitting and crevice corrosion
in seawater (PRENs average 44-46). Formable and weldable. Design stresses at temperatures
up to 400C are given for some types in ASME II. Composition:
20Cr-25Ni-6Mo-1Cu-0.2N Similiar
Specifications: ASTM UNS N08367
20-22%Cr, 23.5-25.5%Ni, 6-7%Mo, 0.18-0.25%N, <2%Mn, <0.03%C <0.75%Cu ASTM
UNS N08925 19-21%Cr, 24-26%Ni, 6-7%Mo, 0.10-0.20%N, <1%Mn, <0.02%C,
0.8-1.5%Cu ASTM UNS N08926 20-21%Cr,
24.5-25.5%Ni, 6.0-6.8%Mo, 0.15-0.25%N, <1%Mn, <0.02%C, 0.8-1.0%Cu DIN/SEW
X1 NiCrMoCuN 25 20 6 1.4529 19-21%Cr, 24-26%Ni, 6-7%Mo, 0.10-0.25%N, <2%Mn, <0.02%C, 0.5-1.5%Cu Applications:
Uses of the superaustenitic 25%Ni20%Cr6.5%MoCu-N steels include: Condenser
and cooling-water piping for power stations and other installations requiring
resistance to seawater. Seawater and product piping systems on offshore
platforms. Duct liners and components for flue gas desulphurization plant.
Plate or frame heat-exchangers. Chloride-contaminated phosphoric and sulphuric
acid solutions. Salt concentration and crystallization. Pulp and paper
plant. Reverse osmosis high pressure piping. Product Forms:
Plate,sheet & strip ASTM UNS N08367 A240 ASTM UNS N08925 A240
ASTM UNS N08926 A240 |