Aluminium 7075 Flat Washers manufactured at TorqBolt are low density,high strength and highly malleable.
Dimensional standards as per DIN 125,ISO 7089,ISO 7090,ISO 7092,DIN 433,DIN 7349,DIN 9021,ISO 7093,F436,BS 4320,UNI 6954 are provided.
The raw material of these fasteners is classified as Non-Ferrous Alloys. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. Aluminium 7075 Flat Washers are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
Aluminium 7075 Flat washers distribute clamp load over a wider bearing area, prevent surface damage, and accommodate bolt-hole oversize. TorqBolt manufactures Aluminium 7075 Flat 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
Aluminium 7075 Flat 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
Aluminium 7075 Flat 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 Aluminium 7075 Flat 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.
Aluminium Alloys
Aluminium alloys are specified for fasteners where weight reduction, electrical conductivity, or non-magnetic / non-sparking properties dominate the design envelope — aerospace structures, marine spars, electronics enclosures, and industries where reducing reciprocating mass directly improves performance. Density of ~2.7 g/cm³ (one-third of steel) combined with self-passivating Al₂O₃ surface gives respectable corrosion resistance in atmospheric service.
2024 (Al-Cu-Mg) is the high-strength aerospace alloy: yield ~325 MPa in T3 condition, used for airframe structural fasteners. 6061 (Al-Mg-Si) is the general-purpose grade with excellent weldability and corrosion, the standard for marine + structural fasteners. 7075 (Al-Zn-Mg-Cu) is the highest-strength aluminium fastener alloy: yield ~505 MPa in T6 condition, comparable to mild steel at one-third the weight — the dominant material for civilian + military aircraft assembly.
Aluminium fasteners ship per AMS 7222 / 7223 / ASTM F468 (rod) with full mechanical certification including hardness (Rockwell B 60-87), tensile, and conductivity testing. Galvanic isolation is critical when aluminium fasteners contact dissimilar metals in moist environments — cadmium plating or insulating washer + sleeve combinations are commonly specified.
