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Alloy Steel dealers in UAE

EN30B / 835M30 / 36NiCrMo16 / 1.6773

EN30B / 835M30 (closest DIN: 36NiCrMo16, 1.6773) - the highest-alloy grade in the BS 970 NiCrMo through-hardening series. Ni 3.90-4.30%. Reliable Q&T through-hardening to 300+ mm diameter. Specified for very large forgings, heavy shafts, and ultra-high toughness applications where EN26 hardenability is insufficient. Specialist indent grade with extended lead times.

Industries Served

Oil & Gas
Power Generation
Heavy Engineering
Aerospace & Defense
Mining

Applications

  • Very large diameter oil & gas downhole tool blanks, heavy BHA mandrels, and large drill collar preforms exceeding 250 mm diameter where EN26 hardenability is insufficient
  • Heavy forged power generation turbine shafts, large generator rotor forgings, and steam turbine disc forgings requiring uniform through-section Q&T properties above 250 mm
  • Large marine propulsion shafts, stern tube shaft forgings, and heavy propeller shaft components requiring consistent mechanical properties through 300-400 mm sections
  • Heavy mining machinery mainshafts for gyratory and jaw crushers, large mill drive shafts, and mining hoist drum shafts in extreme section sizes
  • Nuclear pressure vessel heavy forgings, reactor vessel closures, and large-diameter pressure-retaining bolting requiring maximum through-section toughness
  • Defence ordnance components, large-calibre gun barrel forgings, and heavy armoured vehicle drivetrain shafts requiring maximum strength and toughness in very large sections
  • Large offshore platform pin connections, mooring system components, and heavy structural forgings in subsea or arctic environments requiring exceptional low-temperature toughness
  • Large hydraulic press cylinder forgings, heavy press ram shafts, and industrial press machine main drive components in sections exceeding EN26 hardenability limits
  • Aircraft quality structural forgings to BS 970 EN30B specification where maximum through-section toughness with certified composition and mechanical testing is required
  • Research, prototype, and specialist engineering applications requiring the maximum achievable hardenability from standard-catalogue nickel alloy steel without resorting to maraging or ultra-premium grades

Chemical Composition

0.3 %
C

Carbon

0.26 – 0.34 %

0.2 %
Si

Silicon

0.1 – 0.35 %

0.55 %
Mn

Manganese

0.4 – 0.7 %

P

Phosphorus

≤ 0.035 %

S

Sulphur

≤ 0.04 %

4.1 %
Ni

Nickel

3.9 – 4.3 %

1.25 %
Cr

Chromium

1.1 – 1.4 %

0.27 %
Mo

Molybdenum

0.2 – 0.35 %

Typical value Range (min–max) Minimum (≥) Maximum (≤) Hover / tap for notes

Standard

BS 970 Part 3 - current edition

Available Forms

Round Bar

Diameter 50-600 mm. Forged bar in Q&T or normalised condition, per BS 970 Part 3. EN30B is a large-section specialist grade - primary range 150-400 mm diameter. Available as hot-rolled or forged (forged preferred for large diameters); smaller diameters available but EN26 or 4340 are preferred for economy. Available on indent only - lead times 6-16 weeks from European mills. Contact Nifty Alloys for availability confirmation before quoting to customers.

Designations & Equivalents

StandardDesignationNotes
BSEN30BBS 970 formal designation.
BSEN30BTBS 970 designation for the Q&T condition (T suffix).
BS835M30BS 970 Part 3 designation.
DIN36NiCrMo16Closest DIN grade, not an exact equivalent - Ni 3.60-4.10% vs EN30B 3.90-4.30%. Verify composition on MTC.
EN / Werkstoff1.6773Werkstoff-Nr. of 36NiCrMo16, the closest (not exact) equivalent to EN30B.
ISO36NiCrMo16 (1.6773)Per EN ISO 683-2 - closest equivalent, not exact. No exact DIN/AISI equivalent exists.

Compliance & Certification

StandardStatusNotes
EN 10204 3.1SuitableMill Test Certificate - standard with all supply.
EN 10204 3.2ConditionalIndependent third-party MTC - available on request.
NACE MR0175 / ISO 15156Requires ConfirmationEN30B Q&T acceptable below 22 HRC (248 HB). Standard Q&T (24-32 HRC) typically exceeds the NACE limit. Specify 22 HRC max at order stage and confirm hardness on the MTC for sour service applications.

Specifications

Mechanical Properties

Values are minimums unless noted; hardness is a maximum.

PropertyEN30B / 835M30 — BS 970 Part 3 — Quenched & Tempered (Q&T)DefaultEN30B / 835M30 — BS 970 Part 3 — NormalisedEN30B / 835M30 — EN ISO 683-2 — Annealed
Tensile Strength (UTS)range850–1000 MPaTypical: 925 MPaCondition: Room temp, longitudinal, sections to 250 mmNotes: Per BS 970 Part 3 Q&T. Consistent to 300 mm+ due to extreme hardenability.950–1150 MPaTypical: 1050 MPaCondition: Room tempNotes: Very high normalised strength - harder than many grades Q&T. Do not use in service without Q&T.700–850 MPaTypical: 775 MPaCondition: Room tempNotes: Annealed condition per EN ISO 683-2.
Yield Strength (0.2% Proof Stress)range700–850 MPaTypical: 775 MPaCondition: Room temp680–850 MPaTypical: 765 MPaCondition: Room temp450–600 MPaTypical: 525 MPaCondition: Room temp
Elongationmin14 %Typical: 18 %Condition: 50 mm gauge9 %Typical: 13 %Condition: 50 mm gaugeNotes: Low toughness normalised.16 %Typical: 21 %Condition: 50 mm gauge
Reduction of Areamin50 %Typical: 60 %Condition: LongitudinalNotes: Higher than EN26 at equivalent hardness due to lower carbon and very high Ni toughness.30 %Typical: 45 %Condition: Longitudinal50 %Typical: 60 %Condition: LongitudinalNotes: Good ductility for machining.
Hardnessrange24–32 HRCTypical: 28 HRCCondition: SurfaceNotes: NACE limit: 22 HRC. Standard Q&T NOT NACE compliant.300–380 HBTypical: 340 HBCondition: BrinellNotes: Very hard - hardest normalised condition in the BS 970 series. Do not use in service.220–280 HBTypical: 250 HBCondition: BrinellNotes: Controlled atmosphere annealing required to achieve this.
Impact Energy (Charpy)max95 JCondition: Room temp, V-notchNotes: Very high toughness due to 3.90-4.30% Ni. Even better at -40 degrees C and below.20 JCondition: Room tempNotes: Low - not for service.68 JCondition: Room temp

Physical Properties

PropertyEN30B / 835M30 — BS 970 Part 3 — Quenched & Tempered (Q&T)DefaultEN30B / 835M30 — BS 970 Part 3 — NormalisedEN30B / 835M30 — EN ISO 683-2 — Annealed
Density20 degrees C7.83 g/cm37.83 g/cm37.83 g/cm3
Modulus of Elasticity25 degrees C207 GPa207 GPa207 GPa
Thermal Conductivity100 degrees C30 W/m·K30 W/m·K30 W/m·K
Coefficient of Thermal Expansion20-100 degrees C13 um/m·°C13 um/m·°C13 um/m·°C
Specific Heat Capacity20 degrees C480 J/kg·K480 J/kg·K480 J/kg·K
Melting Point / RangeSolidus1390 degrees C1390 degrees C1390 degrees C
ENGINEERING NOTES
Weldability
Not_recommended

EN30B / 835M30 has very poor weldability due to its extremely high alloy content and carbon equivalent (CE approximately 1.10-1.30). Welding is strongly contraindicated - EN30B components are not welded structures. In the Q&T condition, welding is essentially impossible without destroying the heat treated properties. Any repair welding of EN30B blanks in the annealed condition must be followed by full re-solution anneal and re-Q&T to restore properties - partial re-temper is not acceptable. For any welding consideration, a specialist welding metallurgist must be involved. This is not a grade for general workshop repair. Emergency repair reference only (annealed condition, specialist use): AWS/SMAW very high-strength low-hydrogen electrodes E10018-D2 or E11018-M, preheat 300-400 degrees C, with full re-anneal and re-Q&T mandatory after welding - not for use in the Q&T condition. Consult a welding metallurgist before proceeding.

Machinability
Fair

In the annealed condition (220-280 HB): machinability approximately 50% of AISI 1212 free-machining steel. Carbide tooling strongly recommended. In the Q&T condition (24-32 HRC): carbide tooling essential with reduced cutting speeds and increased cutting depth per pass. Similar to EN26 at equivalent hardness. The very high Ni content means work-hardening can occur - consistent feed rates and avoiding dwelling in the cut are important. Preferred machining sequence: rough machine in annealed condition, Q&T, finish machine or grind to final dimensions.

Overview

EN30B (BS 970 835M30, closest DIN 36NiCrMo16, Werkstoff 1.6773) is the highest-alloy grade in the BS 970 nickel-chromium-molybdenum through-hardening steel series. Containing 3.90-4.30% nickel, 1.10-1.40% chromium, and 0.20-0.35% molybdenum, EN30B represents the apex of standard British specification alloy steel hardenability - reliably through-hardening in sections up to 300 mm or more in oil quench. The very high nickel content provides not only unmatched hardenability in large sections but also exceptional low-temperature toughness and impact resistance significantly surpassing lower-nickel grades at equivalent hardness. EN30B occupies the summit of a progressive grade series - EN8 (carbon) through EN19/4140 (CrMo), EN24/4340 (NiCrMo, 1.65-2.00% Ni), EN26 (NiCrMo, 2.50-3.00% Ni), and finally EN30B (NiCrMo, 3.90-4.30% Ni) - where each step provides improved hardenability for larger sections at progressively higher alloy cost. EN30B is specified exclusively for applications where the section size or toughness requirement cannot be met by EN26 / 826M40.

Nifty Alloys supplies EN30B / 835M30 in round bar on indent from qualified European mill sources. As the highest-alloy grade in this series, EN30B is a specialist indent item with lead times typically 6-16 weeks from mill - it is not a standard stock item. Contact our technical team at the earliest stage of your project to confirm availability, lead times, and pricing before committing to EN30B in your specification. All material is supplied with EN 10204 3.1 Mill Test Certificates as standard. EN 10204 3.2 third-party inspection is available on request. We supply to the UAE, Saudi Arabia, Kuwait, Qatar, Oman, and Bahrain. Contact our team for quotation.

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EN30B / 835M30 (closest DIN 36NiCrMo16) is the highest-alloy grade in the BS 970 NiCrMo through-hardening series, specified exclusively for applications requiring reliable Q&T through-hardening in very large sections (300+ mm diameter) combined with the highest toughness achievable from a standard-catalogue alloy steel. Applications include: very large oil & gas downhole tool blanks and BHA mandrels exceeding 250 mm diameter; heavy forged power generation turbine and generator rotor shafts; large marine propulsion and stern tube shaft forgings; heavy mining crusher mainshafts; nuclear pressure vessel heavy forgings; defence ordnance components in very large sections; offshore mooring and structural forgings requiring exceptional low-temperature toughness to -80 degrees C; heavy press machine drive shafts; aircraft quality structural forgings; and any application where EN26 / 826M40 hardenability at 200-250 mm is still insufficient.

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Ras Al Khor Ind. Area-2, Dubai United Arab Emirtates

+971 565450916

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