Alloy 7010 has been represented as being a high strength/high toughness, and stress corrosion cracking resistant aluminum alloy. Like the 7050 alloy, it is a high purity aluminum alloy using Zr as the grain refiner alloying element rather than Cr. Also, the Cu alloying content is higher than normal for most 7000 series aluminum alloys. Tensile test results indicate the average room temperature tensile strength was 73 KSI (502 MPa) and the yield strength was 64 KSI (440 MPa) for longitudinal grain orientation test specimens. For the same test conditions, the ductility as indicated by an elongation of 13 percent (1 in., 25.4 mm G.L.) was directly comparable to alloy 7175-T73 in the thick plate product form. The average fracture toughness at 72F (22C) for a (L-t) orientation test specimen was 37 KSI sq. rt. in. (40.6 MPa sq. rt. in.) which is approximately equal to alloy 7050-T73651. The material was not found to be corrosion cracking sensitive; the room temperature threshold for stress corrosion cracking in a 3.5% Wt. NaCl solution was determined to be in excess of 70 percent of the room temperature fracture toughness. The materials room temperature constant amplitude fatigue crack growth rate was equivalent to the more cracking resistant 7000 series alloys (7475 and 7050). An increase in the test temperature from 72F (22C) to 250F (121C) caused an increase in excess of 200 percent in the fatigue crack growth rate. A further increase in test temperature to 350 F (176C) caused a small increase in the crack growth rate beyond that existing at 250F (121C).
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