1.1 This specification covers the chemistry requirements for wrought stainless steels used for the manufacture of surgical instruments. The data contained in Tables 1-4 of this specification, including typical hardness values, common heat treating cycles, and examples of selected stainless steels that have been used for surgical instruments, is provided for reference only. Mechanical property requirements, heat treating requirements, hardness requirements and all other requirements except chemistry are governed by the appropriate material standards as referenced below or as agreed upon between the purchaser and supplier.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
TABLE 1 Typical Maximum Hardness for Selected Class 4 Martensitic Stainless Steels in The Annealed ConditionA
| Type | Typical Maximum Brinell HardnessB |
| 410 | 210 |
| 410X | 220 |
| 416 | 262 |
| 416 Mod | 262 |
| 420A | 220 |
| 420B | 235 |
| 420 Mod | 255 |
| 420X | 262 |
| 420C | 262 |
| 420F | 262 |
| 420F Mod | 262 |
| UNS S42027 | 255 |
| 431 | 285 |
| 440A | 285 |
| 440B | 285 |
| 440C | 285 |
| 440F | 285 |
| UNS S42026 | 260 |
| UNS S42010 | 235 |
A Excludes billets and bars for forging.
B Or equivalent Rockwell hardness.
TABLE 2 Typical Heat Treating Cycles and Resultant Hardness Values for Selected Class 4 Martensitic Stainless Steels
| Type | Typical HardeningA Heat Treatment | Typical Hardness at Indicated Tempering TemperatureB | ||||
|---|---|---|---|---|---|---|