AISI 446 Stainless Steel Lock washers manufactured at TorqBolt are corrosion resistant,low maintainence,silver finish.
Dimensional standards as per DIN 6797,DIN 6865 are provided.
The raw material of these fasteners is classified as Martensitic Stainless Steel. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. AISI 446 Stainless Steel Lock washers are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
AISI 446 Stainless Steel Lock washers distribute clamp load over a wider bearing area, prevent surface damage, and accommodate bolt-hole oversize. TorqBolt manufactures AISI 446 Stainless Steel Lock washers per ASME B18.21.1 / B18.22.1, DIN 125 / 126 / 127 / 9021, and ISO 7089 / 7090 / 7093 / 7094, in metric (M3–M100) and imperial (#4–4") sizes.
Plain Washer Dimensions
AISI 446 Stainless Steel Lock plain washers are characterized by three critical dimensions: ID (clearance over bolt diameter), OD (load distribution area), and thickness (compressive stiffness). Standard tolerances are h13 on OD and H13 on ID per ISO 286-2; flatness 0.05 mm/100 mm and parallelism 0.05 mm/100 mm verified per lot. Edge break / chamfer per drawing.
Form Variants
Form A (regular) — DIN 125-A / ISO 7089, the default plain washer
Form B (large OD) — DIN 9021 / ISO 7093, for soft mating surfaces
Form C (heavy) — DIN 7349 / ISO 7094, for slotted holes / structural use
Spring (split) — DIN 127 / ASME B18.21.1, helical anti-vibration
Conical / Belleville (DIN 6796 / 2093) — preload maintenance
Hardness & Surface
AISI 446 Stainless Steel Lock washers are hardness-controlled to balance load-distribution stiffness against surface damage to mating parts. Typical Vickers HV ranges: plain 140–180 HV; spring 380–440 HV; Belleville 460–540 HV. Surface finish Ra 1.6 µm or better; on critical sealing applications, Ra 0.8 µm available.
Special Patterns
TorqBolt produces AISI 446 Stainless Steel Lock washers in square (DIN 436), fender (oversized OD), tab / lock-tang (DIN 462 / 463), and spherical seat washer + cup combinations. EN 10204 3.1 / 3.2 material certificates standard; NACE MR0175 / ISO 15156 on request.
Martensitic Stainless Steel (400-series)
Martensitic stainless steels are body-centered tetragonal Fe-Cr alloys (typically 12-17% Cr, >0.1% C) that respond to quench + temper heat treatment, achieving high hardness and tensile strength while retaining moderate corrosion resistance. They are magnetic and used where mechanical strength is critical and corrosion exposure is mild.
AISI 410 (UNS S41000) is the general-purpose grade for valve trim, pump shafts, turbine blades, and high-strength bolting; quench from 950-1010°C + temper at 200-700°C dial in tensile strength from 600 to 1200 MPa. AISI 416 is the free-machining variant (S+P additions). AISI 420 raises C for higher hardness (cutlery, surgical instruments). AISI 431 adds Ni for marine + aerospace fasteners. AISI 440A/B/C are the highest-hardness grades (HRC 56-60) for bearings and ball valves.
Martensitic fasteners are supplied per ASTM A276 / A479 with hardness, tensile, and impact testing per the heat-treat condition. EN 10204 3.1 / 3.2 certs standard. NACE MR0175 service is restricted — martensitic grades are SSC-susceptible above HRC 22 hardness, requiring careful temper-control for sour applications.
