PAM,
You have got to start reading from better books....
The materials that you refer to are typically found in cast carbon steel components.... (valve bodies, for example,would be made from A217 ).
Cast materials approved for use in ASME Section III Nuclear Power systems, are listed in ASME Section II. All cast ASME approved nuclear power materials begin with the "SA" prefix. "SA" indicates compliance with ASME ....."A" prefix indicates an ASTM material (In many cases the materialis the same)
Hope that this helps !!??!!
MJC