MP35N Alloy Supplier – AMS 5844 / AMS 5845 Bar, Rod & Wire

ASC LLP supplies MP35N alloy (UNS R30035) round bar, hex bar, rod and cold-drawn bar stock – including MP35N AMS 5844 bar – to AMS 5844, AMS 5845 and AMS 5758, plus NACE MR0175 material for sour service – with full mill test certificates and export packing.

What is MP35N Alloy?

MP35N is a nickel-cobalt-chromium-molybdenum alloy – roughly 35% nickel, 35% cobalt, 20% chromium and 10% molybdenum. The name stands for “multiphase”: cold working transforms part of its structure into a very fine second phase, and a low-temperature aging treatment then raises its strength even further. The result is one of the strongest corrosion-resistant alloys available – tensile strengths of 260–300 ksi (about 1,800–2,070 MPa) are typical in the cold-worked and aged condition – while it stays tough, ductile and non-magnetic.

MP35N is not a stainless steel: it contains almost no iron. Its strength comes from cold work and aging rather than from heat-treating, which is why it is supplied in specific conditions – AMS 5758 (solution treated), AMS 5844 (solution treated and cold drawn) and AMS 5845 (cold drawn and aged). It is also produced to ASTM F562 for medical devices and is listed in NACE MR0175 for sour oil and gas service.

MP35N round bar – AMS 5844 – ASC LLP

Key Properties of MP35N

  • Ultra-high strength: up to about 300 ksi tensile strength after cold work and aging.
  • Outstanding corrosion resistance: excellent in seawater, chlorides, mineral acids and sour (H₂S) environments.
  • Resistance to stress-corrosion cracking and hydrogen embrittlement: the main reason it is chosen for subsea and downhole parts.
  • Toughness and fatigue strength: retains ductility at very high strength levels and down to cryogenic temperatures.
  • Non-magnetic and biocompatible: used in pacemaker leads, guidewires and other medical devices (ASTM F562).
  • Service temperature: suitable for use up to about 315 °C (600 °F).

MP35N Forms We Supply

MP35N Round Bar & Rod

Cold-drawn and centreless-ground MP35N round bar to MP35N AMS 5844 and AMS 5845 – the most common form for aerospace fasteners, shafts and downhole tool parts.

MP35N Hex Bar

MP35N hex bar for bolts, nuts and fittings, reducing machining time and material waste.

Cold-Drawn MP35N Bar Stock

Precision-tolerance MP35N bar stock with a bright finish, ready for CNC machining.

AMS 5758 Solution-Treated Bar

Softer, solution-treated MP35N bar for parts that will be formed or heavily machined before final strengthening.

NACE MR0175 MP35N Round Bar

Material qualified for sour gas service where resistance to sulfide stress cracking is essential.

MP35N bar stock
Alloy round bars in stock

MP35N Bar Size Range (UNS R30035)

Size (Diameter) Length Tolerance
0.125″ (3.175 mm) 12 ft (3.66 m) ±0.001″ (0.025 mm)
0.250″ (6.35 mm) 12 ft (3.66 m) ±0.002″ (0.051 mm)
0.375″ (9.525 mm) 12 ft (3.66 m) ±0.002″ (0.051 mm)
0.500″ (12.7 mm) 12 ft (3.66 m) ±0.003″ (0.076 mm)
0.625″ (15.875 mm) 12 ft (3.66 m) ±0.003″ (0.076 mm)
0.750″ (19.05 mm) 12 ft (3.66 m) ±0.004″ (0.102 mm)
1.000″ (25.4 mm) 12 ft (3.66 m) ±0.004″ (0.102 mm)
1.250″ (31.75 mm) 12 ft (3.66 m) ±0.005″ (0.127 mm)
1.500″ (38.1 mm) 12 ft (3.66 m) ±0.005″ (0.127 mm)

Standard stock lengths shown; other diameters, hex sizes and cut lengths on request.

MP35N AMS 5844 vs AMS 5845 vs AMS 5758 – Conditions & Properties

Specification Condition Tensile strength (typical) Yield strength (typical) Elongation Hardness
AMS 5758 Solution heat treated ≈ 130 ksi (900 MPa) ≈ 55 ksi (380 MPa) ≈ 65% ≈ 90 HRB
AMS 5844 Solution treated + cold drawn ≈ 255 ksi (1,760 MPa) ≈ 225 ksi (1,550 MPa) ≈ 12% ≥ 45 HRC
AMS 5845 Solution treated + cold drawn + aged 260 – 300 ksi (1,790 – 2,070 MPa) ≈ 240 – 280 ksi ≈ 10% ≈ 48 – 54 HRC

In short: MP35N AMS 5844 is the cold-drawn bar most buyers ask for; AMS 5845 is the same bar after an aging treatment (around 540–595 °C / 1,000–1,100 °F) for maximum strength; AMS 5758 is the soft, solution-treated condition. Values are typical and depend on bar size and the amount of cold work – guaranteed minimums are shown on the mill certificate.

MP35N Specifications & Designations

System Designation
UNS R30035
AMS (aerospace) AMS 5758, AMS 5844, AMS 5845
Medical ASTM F562, ISO 5832-6
Oil & gas NACE MR0175 / ISO 15156
Common names MP35N®, alloy MP35N, 35N LT (low-titanium medical variant)
Shapes Round, hex, flat, square, rod and wire
Finish Cold drawn, bright, centreless ground, peeled
Test certificate EN 10204 3.1; third-party inspection on request

MP35N Chemical Composition (UNS R30035)

Element Composition (wt %)
Nickel (Ni) 33.0 – 37.0
Chromium (Cr) 19.0 – 21.0
Molybdenum (Mo) 9.0 – 10.5
Titanium (Ti) 1.0 max
Iron (Fe) 1.0 max
Manganese (Mn) 0.15 max
Silicon (Si) 0.15 max
Carbon (C) 0.025 max
Phosphorus (P) 0.015 max
Sulphur (S) 0.010 max
Boron (B) 0.015 max
Cobalt (Co) Balance (≈ 35)

Physical Properties of MP35N

Property Value (approx.)
Density 8.43 g/cm³ (0.304 lb/in³)
Melting range 1,315 – 1,440 °C (2,400 – 2,625 °F)
Modulus of elasticity ≈ 233 GPa (33.8 × 10⁶ psi)
Magnetic Non-magnetic
Maximum service temperature ≈ 315 °C (600 °F)
Industrial applications of MP35N bars

MP35N Machinability

MP35N work-hardens quickly, so MP35N machinability is poor compared with steels – plan for it:

  • Machine in the softest condition practical (AMS 5758 or AMS 5844), and age to AMS 5845 afterwards where the design allows.
  • Use rigid machines and fixtures, sharp carbide tools with positive rake, low cutting speeds and heavy, constant feeds – never let the tool rub.
  • Use plenty of coolant; for threads, thread rolling gives better fatigue life than cutting.
  • Grinding is preferred for close tolerances on hardened bar.

Corrosion Resistance & NACE MR0175

MP35N resists pitting, crevice corrosion and stress-corrosion cracking in seawater and chloride brines, and is one of the few ultra-high-strength alloys accepted in NACE MR0175 / ISO 15156 for sour (H₂S) service. Its resistance to hydrogen embrittlement makes it suitable for subsea fasteners and cathodically protected parts.

MP35N vs Inconel 718

Property MP35N (AMS 5845) Inconel 718 (aged)
Base Ni-Co-Cr-Mo Ni-Cr-Fe-Nb
Tensile strength (typical) 260 – 300 ksi ≈ 180 – 200 ksi
Strengthening Cold work + aging Precipitation hardening
Corrosion / SCC resistance Excellent Very good
Best above 600 °C No Yes (to ≈ 650 °C)
Typical use Fasteners, springs, medical, sour service Turbine parts, high-temperature bolting

Read the full comparison: MP35N round bars vs Inconel 718 – which alloy suits your needs?

Applications of MP35N

  • Aerospace: high-strength fasteners, landing-gear and actuator parts, cables and springs.
  • Oil & gas: downhole tools, wireline, subsea fasteners and sour-service components.
  • Marine: seawater-exposed shafts, fasteners and springs.
  • Medical: pacemaker leads, guidewires and orthopaedic parts (ASTM F562).
  • Chemical processing: high-strength parts in corrosive service.

More on MP35N: MP35N in space exploration · MP35N aircraft fasteners · MP35N in oil, gas & marine

Related Alloy Bars Grades

Why Buy MP35N from ASC LLP?

  • Certified material: AMS 5844 / 5845 / 5758 and NACE MR0175, with EN 10204 3.1 certificates and full traceability.
  • Range: round bar, hex bar, rod and cold-drawn bar stock in a wide size range.
  • Cut-to-length: small quantities and cut pieces for prototypes and fastener runs.
  • Testing: PMI, hardness and third-party inspection on request.
  • Technical support: help choosing between AMS 5844, AMS 5845 and alternatives such as Inconel 718 or CoCrMo.

Frequently Asked Questions – MP35N

What is MP35N?

MP35N (UNS R30035) is a nickel-cobalt-chromium-molybdenum alloy of about 35% Ni, 35% Co, 20% Cr and 10% Mo. Cold working and aging give it tensile strengths up to about 300 ksi together with excellent corrosion resistance.

What is the difference between AMS 5844 and AMS 5845?

AMS 5844 covers MP35N bar in the solution-treated and cold-drawn condition. AMS 5845 is the same material after an additional aging treatment, which raises strength and hardness slightly and lowers elongation.

Is MP35N a stainless steel?

No. MP35N is a nickel-cobalt superalloy with almost no iron. It is far stronger than stainless steel and more resistant to stress-corrosion cracking.

Is MP35N magnetic?

No. MP35N is non-magnetic in all conditions, which is one reason it is used in medical and electronic applications.

How hard is MP35N?

Solution-treated MP35N is about 90 HRB. AMS 5844 cold-drawn bar is about 45 HRC or more, and aged AMS 5845 bar typically reaches 48–54 HRC.

Is MP35N difficult to machine?

Yes. MP35N work-hardens rapidly, so it needs rigid set-ups, sharp carbide tools, low speeds, constant feeds and plenty of coolant. Machining before aging is easier.

Is MP35N NACE compliant?

Yes. MP35N is listed in NACE MR0175 / ISO 15156 for sour oil and gas service when supplied in the permitted condition and hardness.

MP35N vs Inconel 718 – which is stronger?

MP35N in the aged AMS 5845 condition is stronger (about 260–300 ksi) than aged Inconel 718 (about 180–200 ksi) and more resistant to SCC, but Inconel 718 is better above about 600 °C.

Global Reach

ASC LLP supplies MP35N and other high-performance alloys to aerospace, medical, oil & gas and marine customers worldwide, with prompt delivery and full documentation. Buyers in the USA, Europe, the Middle East and Asia rely on our MP35N bar stock for certified properties and traceability.

ASC LLP global export of MP35N alloy

Countries We Export To

UNITED STATES, EUROPE, UK, UAE, SAUDI ARABIA, OMAN, KUWAIT, JORDAN, QATAR, INDONESIA, MALAYSIA, BRAZIL, SPAIN, ITALY, FRANCE, GERMANY, BAHRAIN, SRI LANKA, AZERBAIJAN, AUSTRALIA, AUSTRIA, PHILIPPINES, TURKEY, RUSSIA, IRAN, IRAQ, CANADA, KOREA, JAPAN, YEMEN, FINLAND, ZIMBABWE, HUNGARY, PORTUGAL, VIETNAM, MOROCCO, THAILAND, SOUTH AFRICA, MEXICO, SINGAPORE, GREECE, KUWAIT, POLAND, NEW ZEALAND, SWEDEN, SWITZERLAND, BELGIUM, BHUTAN, BANGLADESH, TAIWAN, ROMANIA, CAMBODIA, KAZAKHSTAN, AFGHANISTAN.

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