... ISO 9328-2:1991 N: normalized; NT: normalized and tempered ISO 9328-3:1991 N: normalized; NT: normalized and tempered; NNT: double-normalized and tempered; QT: quenched and tempered ISO ... Weight, %, Maximum, Unless Otherwise Specified Standard Designation Grade, Class, Type, Symbol or Name Steel Number UNS Number t, mm t, in. C Mn Si P S Cr Ni Mo Others Gr. 100 [690] & ... Treatmentt, mm t, in. N/mm2 or MPa ksi N/mm2 or MPa ksi Elongation, min, % Other < 3 235 360-510 20 ISO 5952:1998 Gr. HSA 235W Class B, D HR ≥ 3 235 340-470 22 t ≤ 3 ...