Element composition (%) <
Crade/UNS	C	O	N	H	Fe	Mo	Zr	Ni	Si	Ti	Al	Ta	Hf≥99.8%
R1	0.015	0.04	0.05	0.0025	0.025	0.002	0.02	0.05	0.01	0.01	0.01	0.02	remaining
R3	0.025	0.13	0.05	0.005	0.025	--	0.02	0.05	0.05	0.05	0.05	--	remaining