ASTM F436 Technical Data
Order F436 Flat Washers
Order F436 Bevel Washers
This specification covers the chemical, mechanical, and dimensional requirements for hardened steel washers for use with fasteners having nominal thread diameters of 1/4 through 4 in. and M12 through M100. These washers are intended for general-purpose mechanical and structural use with bolts, nuts, studs, and other internally and externally threaded fasteners.
Chemical Requirements
| Composition, % | ||
| Element | Type 1 | Type 3B |
| Phosphorus, max | ||
| Heat analysis | 0.040 | 0.040 |
| Product analysis | 0.050 | 0.045 |
| Sulfur, max | ||
| Heat analysis | 0.050 | 0.050 |
| Product analysis | 0.060 | 0.055 |
| Silicon | ||
| Heat analysis | 0.15-0.35 | |
| Product analysis | 0.13-0.37 | |
| Chromium | ||
| Heat analysis | 0.45-0.65 | |
| Product analysis | 0.42-0.68 | |
| Nickel | ||
| Heat analysis | 0.25-0.45 | |
| Product analysis | 0.22-0.48 | |
| Copper | ||
| Heat analysis | 0.25-0.45 | |
| Product analysis | 0.22-0.48 | |
AWhen providing Weathering Steels to a calculated corrosion index use the Legault-Leckie formula from Guide G101.
Link to online calculator: http://www.astm.org/COMMIT/G01_G101Calcultr1100.xls
+ 1.49 (% Si) + 17.28 (% P) - 7.29 (% Cu) (% Ni)
- 9.10 (% Ni) (% P) - 33.39 (% Cu)2
B Weathering steel washers may also be manufactured from any of the steels listed in Table 2 of Specification A588/A588M and F3125.
Washer Dimensional Tolerances
| Dimensional Characteristics | <1 in. Nominal Size | 1 through 1 1⁄2 in. Nominal Size | >1 1⁄2 through 3 in. Nominal Size | >3 in. Nominal Size |
| Flatness: max deviation from straightedge placed on cut side shall not exceed (in.) | 0.010 | 0.015 | 0.020 | 0.032 |
| Concentricity, in.: center of hole to outside diameter | 0.030 FIRA | 0.060 FIRA | 0.090 FIRA | 0.250 FIRA |
| Burr shall not project above immediately adjacent washer surface more than (in.) | 0.010 | 0.015 | 0.020 | 0.025 |
AFull indicator reading.