Mp 35n Allen Screws Specification

MP 35N Equivalent Designation
| UNS Designation | British STD | Werkstoff No. | European STD | Swedish STD | Japanese STD |
|---|---|---|---|---|---|
| – | – | – | – | – | – |
Mp 35n Allen screws are externally threaded fasteners typically driven into a tapped hole or self-tapped material. TorqBolt manufactures Mp 35n Allen screws per ASME B18.3 (socket products), ASME B18.6.3 (machine screws), DIN 912 / 7991 / 6912, and ISO 4762 / 10642, in metric M3–M48 and imperial 0–1/2".
Mp 35n Allen screws are available in cap (cylindrical), button (low-profile dome), countersunk / flat (82° or 90°), pan, fillister, truss, and shoulder configurations. Countersunk per DIN 7991 with 90° head angle is standard for metric; 82° per ASME B18.6.3 for imperial.
Mp 35n Allen screws use full-thread or partial-thread (length-under-head) configurations. Machine screws are typically full-thread; cap screws use partial thread for grip control. Threading per ASME B1.1 (UNC/UNF) or ISO 965 (metric coarse/fine), Class 2A or 6g default. Length-under-head is measured from the bearing surface for hex/cap, from the largest face for countersunk. Custom lengths quoted to drawing.
TorqBolt produces Mp 35n Allen set screws (cup-point, cone-point, dog-point, flat-point, hex-socket DIN 913/914/915/916), shoulder screws (precision-ground shoulder for pivot applications), and self-tapping screws (Type AB, Type 25). All certified per EN 10204 3.1 / 3.2 with optional NACE MR0175 sour-service compliance.
MP35N (UNS R30035) is a multiphase nickel-cobalt-chromium-molybdenum alloy combining ultra-high tensile strength with outstanding corrosion resistance — positioned where Inconel 718 lacks sufficient corrosion resistance and Hastelloy C-276 lacks sufficient strength. The cold-work + age-hardening response yields tensile strength >2000 MPa with excellent fatigue and stress-corrosion performance.
The MP35N microstructure is a two-phase mix of fcc + hcp regions; specific cold-work reduction (40-50%) followed by ageing at 540-650°C transforms the matrix to deliver the alloy's signature combination of strength + corrosion resistance. Composition centers on ~35% Ni, 35% Co, 20% Cr, 10% Mo.
MP35N is the dominant material for sour-well wireline + casing bolting, downhole completion equipment, surgical implants requiring biocompatibility + fatigue strength, and high-pressure aerospace fasteners. The alloy is fully qualified to NACE MR0175 / ISO 15156 across the standard hardness range (up to ~52 HRC), making it one of the few materials capable of meeting both extreme-strength and sour-service criteria simultaneously.
MP35N fasteners are supplied per ASTM F562 / AMS 5844 / 5845 with EN 10204 3.2 third-party-witnessed certification including chemistry, mechanicals, hardness, fatigue, and stress-corrosion testing. Welding is generally avoided; mechanical joints with matching MP35N hardware are preferred.