I'm trying to learn the standard nomenclature for the steel and stainless steel mainly used in the bolts, screws, nuts, and other fasteners in general. So far I have created this table:
| Metric / Class | Imperial / Grade | Material | |:-----------------------:|:-------------------:|:----------------------:| | ISO 898-1 / 8.8 | SAE J429 / 5 | steel | | ISO 898-1 / 10.9 | SAE J429 / 8 | Steel | | 12.9 | ASTM A574 | Steel | | 304 | A2 | Stainless steel | | 316 | A4 | Stainless steel |
For example, metric system categories steels into classes according to the ISO 898-1 standard. While the Imperial system uses the SAE J429 standard to distinguish steels by grades. It seems like my table makes sense for steel, but for the stainless steels, I do not understand the grades/classes. For example, I'm not sure if 316 designates a metric class equivalent to the A4 imperial grade?
From time to time I also see notations such as A4-80 EPK
. I understand that the 80
part determines the minimum tensile strength. But I have no clue what the EPK could stand for.