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Model No: ASTM F562 MP35N Cobalt Alloy
ASTM F688 / ASTM F562 - MP35N Cobalt Alloy
MP35N supplied by Lork Group is delivered in strict accordance with ASTM F688 (plate/strip/foil) or ASTM F562 (bar) standards, accompanied by a comprehensive Certified Material Test Report (CMTR) that includes chemical composition, mechanical properties, grain size, and non-destructive testing data.
Delivery :
FOB
minimum order :
100 kilograms
Supply Ability :
5000Tonkilograms / Month
Stock Time :
7-10Day
Country of Origin :
CHINA
Quantity :
Co-35Ni-20Cr-10Mo Precipitation-Hardening Superalloy | Ultra-high Strength / Non-magnetic / SCC Resistant | Specialized for Medical, Aerospace, and Oil & Gas Applications
There are many common cobalt-chromium alloys—such as L605 (Haynes 25)—that offer respectable strength, exceeding 1,900 MPa. While 316L stainless steel is inexpensive, easy to process, and sufficient for standard environments, MP35N is in a different league. It is not merely"an alloy"but a specialized solution for"extreme operating conditions"; for applications requiring a combination of ultra-high strength, non-magnetic properties, and resistance to hydrogen sulfide stress corrosion, it stands as one of the few materials with no substitute.
Who is buying it?
- Do the pacemaker leads you manufacture need to bend hundreds of millions of times inside the body without fracturing?
- Must the deep-sea connectors you design withstand seawater corrosion and cyclic loading at depths of 10,000 meters?
- Are the aerospace fasteners you process intended to replace cadmium-plated steel, which is prone to hydrogen embrittlement failure?
- Do your downhole oil and gas tools need to maintain high strength and structural integrity in acidic H₂S environments?
If your equipment operates in an environment with ambient temperatures, no corrosive agents, and low magnetic sensitivity requirements, 304 or 316L stainless steel will suffice. However, if you are grappling with issues like stress corrosion cracking, magnetic interference, or the inability to achieve both high strength and toughness, then read on.
Chemical Composition
The name MP35N is derived from the proportions of its core constituents—35% nickel, 20% chromium, and 10% molybdenum—with the remainder being a cobalt matrix. It relies not on a single element, but on the holistic design of a multi-component strengthening system comprising cobalt, nickel, chromium, and molybdenum.
Typical chemical composition of products supplied by Lork Group (compliant with ASTM F688 / ASTM F562 / UNS R30035)
| Element | Content (%) |
|---|---|
| Cobalt, Co | 35 |
| Nickel, Ni | 35 |
| Chromium, Cr | 20 |
| Molybdenum, Mo | 9.80 |
| Carbon, C | 0.013 |
Impurity levels of manganese (Mn) and silicon (Si) must be strictly controlled, while harmful impurities such as phosphorus (P) and sulfur (S) should be kept as low as possible.
Mechanical Properties
One of the most easily overlooked aspects of MP35N is that, despite having the same chemical composition, its strength can vary by more than twofold depending on the heat treatment and cold-working conditions. It is essential to verify the material condition when purchasing.
| Condition | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Hardness (HRC) | Application Scenarios |
|---|---|---|---|---|---|
| Annealed state | 790 - 965 | ~600 | ≥25 | ~25-30 | When complex machining such as turning, milling, and drilling is required |
| Cold-worked condition (spring temper) | 1400 - 1900 | — | ~8-15 | ~45-50 | Springs, guidewires, and the like do not require subsequent forming. |
| Cold-worked + aged condition (peak strength) | 1900 - 2200 | ~1700-1999 | 8-12 | ~45-55 | Aerospace fasteners, deep-sea tools |
Standard Interpretation: What are the differences between ASTM F688, F562, and AMS 5844?
| Standard | Coverage Form | Primary Use | Key Differences |
|---|---|---|---|
| ASTM F688 | Plates, sheets, and foils | Surgical implants | Specifically for sheet/foil forms |
| ASTM F562 | Bars and wires | Surgical implants | Most commonly used standards for medical implants made of bars or wires |
| AMS 5844 | Bars, wires, and strips | Aerospace | Aerospace-grade specifications; stricter inspection requirements |
⚠️Procurement Notice: When requesting a quote, you must clearly specify the applicable standard. Although MP35N for medical implants and aerospace applications shares the same chemical composition, the requirements for inclusion control, grain size, and non-destructive testing differ. Using industrial-grade material to manufacture pacemaker guidewires would result in a serious incident.
—This is why we insist on discussing all material details before providing a quote. Differences in specifications, quantities, intended use, applicable standards, delivery conditions, and manufacturing processes can lead to price variations of three to five-fold or more. Yet, we remain convinced: the details determine success or failure.
Surface Finishes and Edge Conditions
The trade-off between strength and ductility: Conventional materials achieving a strength of 2000 MPa typically become brittle (with elongation <5%). After cold working and aging, MP35N achieves a tensile strength of 2068 MPa (300 ksi) while maintaining an elongation of 8–12%. It is one of the few material choices for applications—such as springs, guidewires, and fasteners—that demand both high strength and toughness.
Reliability in extremely corrosive environments: In acidic oil and gas wells containing H₂S, many high-strength steels are prone to sudden brittle failure (sulfide stress corrosion cracking, or SSC). MP35N is virtually immune to this type of failure. It also resists pitting corrosion in seawater—a key advantage that allows it to compete with titanium alloys.
Non-magnetic properties and biocompatibility: Implants used near MRI equipment must not heat up or be attracted to the magnetic field. MP35N has low magnetic permeability, meeting the requirements of ASTM A342.
Lork Group – Your Trusted Manufacturer of ASTM F688 / ASTM F562 - MP35N Cobalt Alloy
Lork Group specializes in the production of high-quality ASTM F688-compliant cobalt-chromium-molybdenum alloy (UNS R30035) for surgical implants, including plates, sheets, and foils. Our materials meet stringent medical-grade standards, ensuring exceptional strength, corrosion resistance, and biocompatibility for orthopedic, dental, and cardiovascular applications.
We offer multiple processing options:
- Conditions: Annealed, cold-worked, or cold-worked + aged
- Surface Finishes: Ground, polished, mirror, or custom finishes
- Precision Thickness: From ultra-thin foils (0.05mm) to thick plates (20mm)
With strict quality control (chemical composition, mechanical testing, and grain size analysis), Lork Group guarantees material consistency and performance. Fast lead times and technical support available.
Request a Quote Today!
📧 Email: daisy@lorkgroup.com
📞 Phone: +86 17513081871
