Inconel 602 Flat Washers Specification

Inconel 602 Equivalent Designation
| UNS Designation | British STD | Werkstoff No. | European STD | Swedish STD | Japanese STD |
|---|---|---|---|---|---|
| N06602 | – | 2.4633 | – | – | – |
Inconel 602 Flat washers distribute clamp load over a wider bearing area, prevent surface damage, and accommodate bolt-hole oversize. TorqBolt manufactures Inconel 602 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.
Inconel 602 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.
Inconel 602 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.
TorqBolt produces Inconel 602 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.
Inconel alloys are nickel-chromium-based superalloys engineered for service where standard stainless steels cannot survive. The Inconel family combines high-temperature strength (typically retained up to 700-1100°C depending on grade) with outstanding oxidation and chloride-pitting resistance.
The most widely specified grade is Inconel 718, an age-hardenable Ni-Cr-Fe-Mo-Nb composition strengthened by γ' (Ni₃Al,Ti) and γ'' (Ni₃Nb) precipitates after solution + double-age heat treatment per AMS 5662 / 5663. Inconel 625 is solid-solution strengthened by Mo+Nb, supplied in the as-annealed condition, and weldable without post-weld heat treatment. Inconel X-750 uses Ti+Al precipitation hardening for spring + bolt applications to 700°C. Inconel 600 / 601 are general-purpose grades for furnace and heat-exchanger fasteners.
Typical specifications: ASTM B637 (forged bar), AMS 5662/5663 (rod/bar), ASTM B446 (625 bar), DIN 17752/17754 (round/forged). NACE MR0175 / ISO 15156 sour-service envelopes available on most grades when supplied in the correct heat-treat condition. PREN values for chloride pitting resistance typically exceed 50 across the Inconel range.