Internal Grade	SAE/AISI	IS	BS 970:1955	BS 970:1983	EN	JIS	DIN	GOST	ISO	AFNOR	GB/T	UNI	SS	CSA	AS/NZS
MC1536	1536	37Mn2, 37C15	EN15B	150M36	36Mn5	—	36Mn5	38Mn2	36Mn5	38Mn6	35Mn	36Mn4	—	G15360	AS 1443 1536
MC1018	1015 1016 1018	C14	EN32B	—	C15E	S15C	Ck15	10	C15	XC15	Q235A	C15	1411	G10180	AS 1443 C15
MC1038	1038	—	—	—	C40E	S38C	Ck38	35	C40	XC38	40	C40	—	G10380	AS 1443 C38
HC1050	1050	C50	EN43C	—	C50E	S50C	Ck50	50	C50	XC50	50	C50	1870	G10500	AS 1443 C50
HC1045	1045	45C8	EN8	080A44	C45E	S45C	Ck45	45	C45	XC45	45	C45	1874	G10450	AS 1443 C45
HC1055	1055	C55	EN9	070M55	C55E	S55C	Ck55	55	C55	XC55	55	C55	—	G10550	AS 1443 C55
MC1035	1035	35C8 C35Mn75	—	060A35	C35E	S35C	C35	35	C35	XC35	35	C35	1450	G10350	AS 1443 C35
HC1074	1074	80C6	EN42	—	C75E	SK85	Ck75	75	C75	XC75	75	C75	—	G10740	AS 1443 C75
HC1065	1065	65C6	EN42B	—	C67E	SK85	C67	70	C67	XC65	65	C67	—	G10650	AS 1443 C67
HC1055B	1055	60C6	EN43	080M50	C50E	S50C	C55	55	C50	XC50	50	C50	—	G10550	AS 1443 C50
HC1045B	1045	—	EN43B	080A47	C45E	S45C	CK45	45	C45	XC45	45	C45	—	G10450	AS 1443 C45
MC1541	1541	37C15	EN15	150M36	36Mn5	SMn438	36Mn7	38Mn2	—	—	35Mn	—	—	G15410	AS 1443 1541
HC1045X	1040 1045	45C8	EN8A EN8B EN8C EN8D	080A40	C45E	S45C	CK45	45	C45	XC45	45	C45	—	G10450	AS 1443 C45

Note: Internal Grade names follow a consistent pattern: MC for Medium Carbon and HC for High Carbon. Some closely related variants (e.g., EN8 family) are grouped to avoid redundancy. This table focuses only on steels suitable for bar or wire applications. Always confirm mechanical and heat treatment requirements before interchange.