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Search for EN8, and find AISI 1040 Steel, available with various heat & mechnical treatment. One specific example:
"AISI 1040 Steel, oil quenched from 855°C (1570°F), 595°C (1100°F) temper, 100 mm (4 in.) round
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Key Words: UNS G10400, ASTM A29, ASTM A108, ASTM A510, ASTM A519, ASTM A546, ASTM A576, ASTM A682, MIL SPEC MIL-S-11310 (CS1040), SAE J403, SAE J412, SAE J414, DIN 1.1186, JIS S 40 C, BS 970 060A40, BS 970 080A40,
BS 970 080M40 (EN8), BS 2 S 93"
Composition & properties are given, & sometimes supplier links.