| Internal Grade | SAE/AISI | IS | BS 970:1955 | BS 970:1983 | EN | JIS | DIN | GOST | ISO | AFNOR | GB/T | UNI | SS | CSA | AS/NZS |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| SP9260 | 9260 | 60Si7 | EN45A | 250A58 | EN45A | SUP7 | 60Si7 59Si7 | 60С2А | 683/II-D | 60S7 | 60Si2Mn | 60Si7 | 1870 | G9260 | AS 1444 9260 |
| SP9255 | 9255 | 55Si2Mn90 | EN45 | 250A53 | EN45 | — | 55Si7 | 55С2 | 683/II-B | 55S7 | 55SiMn | 55Si7 | — | G9255 | AS 1444 9255 |
| SP9254 | 9254 | — | — | 685A57 | — | SUP12V | 54SiCr6 | 60С2ХА | — | — | 60SiCrVA | 54SiCr6 | — | G9254 | AS 1444 9254 |
| SP6150 | 6150 | 50Cr4V2 | EN47 | 735A51 | EN47 | SUP10 | 50CrV4 | 50ХФА | 683/II-A | 50CV4 | 50CrVA | 50CrV4 | 2230 | G6150 | AS 1444 6150 |
| SPSUP11A | 51B60 | — | — | — | — | SUP11A | 51CrMoV4 | — | — | — | — | — | — | — | AS 1444 51B60 |
| SPSUP9 | 5155 | — | — | — | — | SUP9 | 55Cr5 | 55ХГ | — | 55Cr3 | 55CrMn | 55Cr3 | — | G5155 | AS 1444 5155 |
| SPSUP6 | 5160 | — | — | 735A50 | — | SUP6 | 60Cr7 | 60ХГСА | 683/II-C | — | 60CrMn | 60Cr7 | 2265 | G5160 | AS 1444 5160 |
Note: Spring steels are chosen for high yield strength and resilience. Grades like 60Si7, 55Si2Mn90, and 51CrV4 are widely used in automotive and industrial springs. Some JIS and SAE variants may require adjustment in tempering for similar results. Equivalent grades provided are for hot-rolled or cold-drawn bars and wires suitable for springs.