X10NiCrSi35-19 forgings

X10NiCrSi35-19 at a glance

EN designation

X10NiCrSi35-19

Material number

1.4886

Nearest UNS

N08330 / Alloy 330

Alloy type

Austenitic Ni-Fe-Cr-Si

Nickel

33–37%

Chromium

17–20%

Silicon

1.0–2.0%

Oxidation resistance in air

to approx. 1000 °C

Delivery condition

Solution annealed

Certification

EN 10204 3.1 / 3.2

Figures are the EN 10095 limits for 1.4886. Order-specific limits take precedence. State the governing specification on the enquiry.

What X10NiCrSi35-19 is used for

X10NiCrSi35-19 (1.4886) holds roughly 35% nickel, 19% chromium and 1 to 2% silicon in an iron matrix. Chromium forms the protective oxide. Nickel keeps the structure austenitic through repeated heating and cooling. Silicon raises resistance to carbon pick-up, and that is the main reason the grade gets specified in place of 310-type stainless steel.

Three failure modes drive the selection: scaling and spallation under thermal cycling, carburisation in hydrocarbon and carbon monoxide atmospheres, and nitriding in low-oxygen nitrogen atmospheres. X10NiCrSi35-19 handles all three. Room-temperature strength is modest, so the grade is chosen for atmosphere resistance rather than load capacity.

Chemical composition of X10NiCrSi35-19

Composition limits below are from EN 10095 for X10NiCrSi35-19 / 1.4886. Iron is the balance.

Where the UNS N08330 limits differ

X10NiCrSi35-19 and UNS N08330 trade as equivalents, but the two specifications differ on carbon and silicon. This matters when a purchase order names one standard and the mill certificate quotes the other.

Heat chemistry that meets UNS N08330 will usually also meet EN 1.4886. The reverse does not hold. If the order has to satisfy both, say so at enquiry stage so the heat can be selected accordingly.

Mechanical and physical properties

Figures below are typical room-temperature minima for X10NiCrSi35-19 in the solution-annealed condition. Certified values on the mill test report follow whatever specification the order names.

Heavy sections cool more slowly than test bar stock, so properties are reported on test material heat treated with the forging. On large sections, agree test location and orientation before production starts.

High-temperature behaviour

X10NiCrSi35-19 holds good oxidation resistance in air to around 1000 °C (1830 °F). The oxide that forms stays adherent through heating and cooling cycles instead of spalling off and exposing fresh metal.

• Carburising atmospheres. Silicon plus high nickel resists carbon pick-up. This is the usual reason the grade replaces 310S in carburising furnace hardware.
• Nitriding atmospheres. Performs well where nitrogen is present and oxygen content is low.
• Alternating carburising and oxidising service. Resistant to green rot, the localised attack that occurs when the two conditions alternate.
• Sulphur-bearing atmospheres. Poor. Sulphide scale flakes instead of protecting, and reducing conditions are worse than oxidising. Published temperature limits do not apply here.

Usable temperature depends on atmosphere, stress level and cycle frequency, not on a single figure. Send service conditions with the enquiry and the selection can be checked against them.

Equivalent grades and related specifications

Product specifications commonly referenced for the N08330 family include ASTM B511 for bars and shapes, ASTM B535 for seamless pipe and tube, ASTM B536 for plate, sheet and strip, and ASTM B710 and B739 for welded pipe and tube. Forgings are supplied to the dimensional and test requirements written into the customer order or drawing.

X10NiCrSi35-19 forged products

Every X10NiCrSi35-19 part is open-die forged or ring rolled to a customer drawing. There is no fixed catalogue, so stepped profiles, odd sections and one-off replacement parts are routine work.

Single-piece weight from a few kilograms to several tonnes. Ring diameter, section and unit weight interact, so confirm the envelope for your part when you enquire.

How X10NiCrSi35-19 forgings are produced

1. Melting. EAF plus AOD or VOD refining, with optional ESR remelting where cleanliness or segregation control is critical.
2. Ingot or billet preparation. Conditioning and cropping before heating, so surface defects are not forged into the part.
3. Open-die forging or ring rolling. Worked within the hot working range of the alloy, with controlled reduction ratio to close porosity and refine grain through the section.
4. Solution annealing. Heat, hold and rapid cool to put carbides back into solution. No ageing step.
5. Rough machining. Turning, boring or facing to give clean surfaces for inspection and to remove the decarburised skin.
6. Non-destructive testing. Ultrasonic examination to EN 10228-3, SEP 1921 or ASTM A388, plus dye penetrant where specified.
7. Certification and release. Chemistry, mechanical results and NDT report issued as EN 10204 3.1, or 3.2 with third-party witness.

Testing, inspection and certification

Standard scope on X10NiCrSi35-19 forgings covers ladle and product chemical analysis, room-temperature tensile testing, hardness, grain size and dimensional inspection, with ultrasonic examination to the acceptance class named on the order.

• Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388
• Liquid penetrant examination to ASTM E165 where surface condition is critical
• Intergranular corrosion testing on request
• Elevated-temperature tensile and impact testing on request
• Certification to EN 10204 3.1, or EN 10204 3.2 witnessed by TUV, BV, SGS, Lloyd's or the customer inspector
• Positive material identification before packing on request

Where X10NiCrSi35-19 forgings are used

The grade goes into service where hot atmosphere rather than pressure is the limiting factor. Common applications for X10NiCrSi35-19 forged parts:

• Heat treatment and furnace equipment. Retort and muffle components, radiant tube supports, roller and fan shafts, hearth fixtures, burner rings.
• Petrochemical and refining. Reformer and cracking furnace hardware, hot-gas nozzles, flanges and rings on high-temperature process lines.
• Cement, lime and mineral processing. Calciner and kiln internals, cooler components, wear parts in hot abrasive service.
• Chemical processing. Reactor and vessel rings, tube sheets, sleeves and bushings in carburising or nitriding atmospheres.
• Power generation and incineration. Supports, hangers and rotating parts operating in hot flue gas.
• Valves and rotating equipment for hot service. Forged bodies, seat rings, stems, spindles and gear blanks where process temperature rules out standard stainless steel.

Getting a quotation

Send a drawing in PDF, STEP or DWG, or a sketch with dimensions. Include:

1. Grade and the governing specification (EN 1.4886, UNS N08330, or a customer spec)
2. Finished dimensions, or forged dimensions with the machining allowance you want
3. Quantity, and whether this is a one-off, a repeat or a call-off
4. Delivery condition: as-forged, solution annealed, rough machined or finish machined
5. Test and certification package required
6. Destination port and required delivery date

Quotations for straightforward geometry normally go out within one working day. Send it to sales@steelforgepieces.com.

Frequently asked questions about X10NiCrSi35-19

Related heat-resistant and nickel alloy forgings

If X10NiCrSi35-19 is not the right fit for your service conditions, these grades cover the neighbouring ground:

• Incoloy 800 forgings, general-purpose Ni-Fe-Cr for moderate high-temperature service
• Incoloy 800H forgings, controlled carbon and grain size for certified creep strength
• Incoloy 800HT forgings, tightened C+N for demanding creep applications
• Inconel 601 forgings, aluminium-bearing, for severe cyclic oxidation
• Inconel 617 forgings, Ni-Cr-Co-Mo for high strength above 900 °C
• Inconel 600 forgings, Ni-Cr for chloride and caustic resistance at temperature
• Haynes 230 forgings, tungsten-strengthened for long-term high-temperature strength
• Hastelloy X forgings, oxidation resistance with good fabricability for combustion hardware
• All nickel alloy forgings