ASTM A747 / A747M

This specification covers iron-chromium-nickel-copper corrosion-resistant steel castings, capable of being strengthened by precipitation hardening heat treatment. These castings may be used in services requiring corrosion resistance and high strengths at temperatures up to 600°F [315°C]. They may be machined in the solution-annealed condition and subsequently precipitation hardened to the desired high-strength mechanical properties

Chemical Properties

Grade	UNS	Carbon	Manganese	Phosphorus	Sulfur	Silicon	Chromium	Nickel	Copper	Columbium	Nitrogen
CB7Cu - 1	J92180	0.07	0.70	0.035	0.03	1.00	14.0 - 15.50	4.50 - 5.50	2.50 - 3.20	0.15 - 0.35A	0.05
CB7Cu - 2	J92110	0.07	0.70	0.035	0.03	1.00	15.50 - 17.70	3.60 - 4.60	2.50 - 3.20	0.15 - 0.35A	0.05

Note A: When the H900 condition is ordered, the minimum columbium content shall not apply.

Mechanical Properties

Grade	PH Heat Treatment	Hardness, HB	Yield Strength 0.2 % Offset, min, ksi [MPa]	Tensile Strength, ksi [MPa]	Elongation in 2 in. [51 mm], min, %A
CB7Cu - 1	H900	375 min	145 [1000]	170 [1170]	5
	H925	375 min	150 [1035]	175 [1205]	5
	H1025	311 min	140 [965]	150 [1035]	9
	H1075	277 min	115 [795]	145 [1000]	9
	H1100	269 min	110 [760]	135 [930]	9
	H1150	269 min	97 [670]	125 [860]	10
	H1150M	310 max	-	-	-
	H1150 DBL	310 max	-	-	-
CB7Cu - 2	H900	375 min	145 [1000]	170 [1170]	5
	H925	375 min	150 [1035]	175 [1205]	5
	H1025	311 min	140 [965]	150 [1035]	9
	H1075	277 min	115 [795]	145 [1000]	9
	H1100	269 min	110 [760]	135 [930]	9
	H1150	269 min	97 [670]	125 [860]	10
	H1150M	310 max	-	-	-
	H1150 DBL	310 max	-	-	-

Note A: If sub-size tension test bars are used, the gage length/gage diameter ratio must be 4 to 1 to assure elongation values comparable with those of the standard test specimen.