Steel, Heat-Resistant, Bars, Forgings, and Tubing 0.95Cr - 0.55Mo - 0.30V (0.40 - 0.50C) Vacuum Arc Remelted.
Melting Practice
Steel shall be multiple melted using consumable electrode vacuum practice (VAR) in the remelt cycle.
Macrostructure
Visual examination of transverse full cross-sections from bars, billets, tube rounds (solid, not hollow), and forging stock,
etched in hot hydrochloric acid in accordance with ASTM A 604, shall show no pipe or cracks. Porosity, segregation, inclusions, and other imperfections shall be no worse than the macrographs of ASTM A 604 shown in Table 2.
Average Grain Size of Bars, Forgings and Tubing
Shall be ASTM No. 5 or finer, determined in accordance with ASTM E 112.