Uranus B26 6Mo is Aperam/Industeel's trade name for the nickel-based superaustenitic alloy widely known as Alloy 926, UNS N08926, EN 1.4529. It sits directly alongside its sibling Uranus B25 6Mo in the 6-Mo family — both carry roughly 6-7% molybdenum and a nitrogen addition that push PREN (pitting resistance equivalent) to around 43 — but B26 flips the balance of chromium and nickel: where B25 is built on a 20Cr-18Ni base, B26 runs closer to 20Cr-25Ni, with nickel becoming the dominant alloying element rather than chromium.
That higher nickel content buys two things B25 doesn't offer as strongly: greater structural stability during welding and heat treatment (lower risk of embrittling intermetallic phases forming), and toughness that holds up at cryogenic temperatures down to roughly -196°C. Combined with a copper addition, Uranus B26 6Mo is specified for chemical and petrochemical processing equipment, flue gas desulfurization, and other severely corrosive service where both chloride resistance and long-term structural stability matter — including welded fabrications where B25's slightly leaner nickel content would carry more phase-stability risk.
| Standard | Designation |
|---|---|
| UNS | N08926 |
| Wnr. (Werkstoffnummer) | 1.4529 |
| DIN / EN | X1NiCrMoCuN25-20-7 |
| ASTM | A240 (plate/sheet); ASTM B649 (bar/wire) |
| Element | Content |
|---|---|
| Nickel (Ni) | 24.0 – 26.0% |
| Chromium (Cr) | 19.0 – 21.0% |
| Molybdenum (Mo) | 6.0 – 7.0% |
| Copper (Cu) | 0.50 – 1.50% |
| Nitrogen (N) | 0.15 – 0.25% |
| Manganese (Mn) | 1.00% max |
| Silicon (Si) | 0.50% max |
| Carbon (C) | 0.020% max |
Composition per UNS N08926 (Alloy 926). Estimated PREN (Cr + 3.3×Mo + 16×N) is approximately 43, comparable to Uranus B25 6Mo but with a nickel-dominant rather than chromium-dominant alloy balance.
Uranus B26 6Mo cuts much like B25 6Mo — both are fully austenitic 6-Mo superaustenitic grades with cutting forces and heat generation well above 316, driven by high combined molybdenum, chromium, and nickel content rather than any ferrite phase. The higher nickel fraction in B26 pushes its ductility and gumminess slightly further than B25's leaner nickel base, meaning the tendency to smear and work-harden under a rubbing or dull edge is, if anything, a bit more pronounced here.
The same fundamentals apply as with any 6-Mo superaustenitic: sharp, positive-rake inserts with a stainless-rated chipbreaker to shear the material cleanly rather than let it drag, firm and consistent feed rates to keep the edge engaged, and strong coolant delivery to manage heat that the alloy's low thermal conductivity won't carry away on its own. Rigidity in both machine and workholding matters more here than on 316 or even standard duplex — any deflection invites work hardening on the next pass.
| Operation | Vc (m/min) | Vc (SFM) |
|---|---|---|
| Turning | 155 – 195 | 510 – 640 |
| Milling | 95 – 125 | 310 – 410 |
| Parting | 60 – 80 | 200 – 260 |
| Grooving | 90 – 120 | 300 – 390 |
| Drilling | 45 – 55 | 150 – 180 |
Values assume favorable conditions: a well-matched insert grade, rigid tool and workpiece clamping, good raw material quality, short tool overhang, and adequate coolant. Run toward the lower end of each range given this alloy's high nickel and molybdenum content.
| Grade | Coating | ISO Application Range |
|---|---|---|
| FM324 | PVD | M10 – M20 |
| FM2553 | CVD | M30 |
| Grade | Coating | ISO Application Range |
|---|---|---|
| FM2543 | CVD | P20 |
| FM2553 | CVD | M30 |
| Grade | Coating | ISO Application Range |
|---|---|---|
| FM125 | PVD | M15 – M35 |
Ready to cut Uranus B26 6Mo? Shop FM Carbide inserts matched to this alloy's turning, parting, grooving, and milling requirements.
Shop Turning & Grooving Inserts Shop Milling Inserts| Parameter | Value |
|---|---|
| Honing Size | 0.03 – 0.05 mm / 0.001 – 0.002" |
| Rake Angle | 9° – 11° |
| Land Angle | Positive |
| Land Width | 0.20 – 0.30 mm / 0.008 – 0.012" |