ASTM A403

Chemical Composition (%) of ASTM A403

Steel No.	Type	Chemical composition
Steel No.	Type	C	Si	S	P	Mn	Cr	Ni	Mo	Other	ób	ós	δ5
WP304	0.08	1	0.03	0.045	2	18-20	8-11			515	205	28
WP304H	0.04-0.1	1	0.03	0.045	2	18-20	8-11			515	205	28
WP304L	0.035	1	0.03	0.045	2	18-20	8-13			485	170	28
WP304LN	0.03	0.75	0.03	0.045	2	18-20	8-10.5		N2:0.1-0.16	515	205	28
WP304N	0.08	0.75	0.03	0.045	2	18-20	8-11		N2:0.1-0.16	550	240	28
WP309	0.15	1	0.03	0.045	2	22-24	12-15			515	205	28
WP310	0.15	1.5	0.03	0.045	2	24-26	19-22			515	205	28
WP316	0.08	1	0.03	0.045	2	16-18	10-14	2-3		515	205	28
WP316H	0.04-0.1	1	0.03	0.045	2	16-18	10-14	2-3		515	205	28
WP316LN	0.03	0.75	0.03	0.045	2	16-18	11-14	2-3	N2:0.1-0.16	515	205	28
WP316L	0.035	1	0.03	0.045	2	16-18	10-16	2-3		485	170	28
WP316N	0.08	0.75	0.03	0.045	2	16-18	11-14	2-3	N2:0.1-0.16	550	240	28
WP317	0.08	1	0.03	0.045	2	18-20	11-15	3-4		515	205	28
WP317L	0.03	1	0.03	0.045	2	18-20	11-15	3-4		515	205	28
WP321	0.08	1	0.03	0.045	2	17-20	9-13		Ti:5C-0.7	515	205	28
WP321H	0.04-0.1	1	0.03	0.045	2	17-20	9-13		Ti:4C-0.7	515	205	28
WP347	0.08	1	0.03	0.045	2	17-20	9-13		Nb+Ta:10C-1.1	515	205	28
WP347H	0.04-0.1	1	0.03	0.045	2	17-20	9-13		Nb+Ta:8C-1	515	205	28
WP348	0.08	1	0.03	0.045	2	17-20	9-13		Ta:0.1	515	205	28
WP348H	0.04-0.1	1	0.03	0.045	2	17-20	9-13		Ta:0.1	515	205	28

Notes:

For each reduction of 0.01% below the specified C maximum, an increase of 0.06% Mn above the specified maximum will be permitted, up to a maximum of 1.35%.

The sum of Cu, Ni, Cr, and Mo shall not exceed 1.00%.

The sum of Cr and Mo shall not exceed 0.32%.

The maximum carbon equivalent (C.E.) shall be 0.50, based on heat analysis and the formula C.E.=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15.