ASTM A515 is a grade under ASTM standard of boiler and pressure vessel steel. Refer to A515 gr.70 Chemical composition,A515 gr.70 Mechanical properties,A515 gr.70 shall be killed and made to a coarse austenitic grain size practice. A515 gr.70 steel shall conform to the chemical requirements specified. Tension test shall be made to conform to the requirements specified. ASTM A515 gr.70  chemical composition :

Grade	C (max)					Si (max)	P (max)	S (max)	Mn (max)
	< 12.5 mm	12.5< t ≤50mm	50< t ≤100mm	100< t ≤200mm	t>200mm
A515 gr.70	0.31	0.33	0.35	0.35	0.35	0.15-0.4	0.035	0.035	1.2

ASTM A515 gr.70  mechanical properties :

Grade	Tensile strength Rm for product thickness in mm	Upper yield stress ReH for product thickness in mm	Elongation after fracture (Lo=5 do) % min
A515 gr.70	480-620	260	17/21

ASTM A 515 includes three different levels, gr.60,gr.70,gr.65. So if you need more information about A515 gr.70 Chemical composition,A515 gr.70 Mechanical properties,A515 gr.65 Chemical composition,A515 gr.65 Mechanical properties,A515 gr.60 Chemical composition,A515 gr.60 Mechanical properties