7178 aluminum alloy is wrought alloy. It has high zinc content. After annealing, aluminum alloy 7178 has high machinability. Resistance welding can be used.
Chemical composition The chemical composition of Aluminium / Aluminum 7178 alloy is outlined in the following table. It is difficult to cold work. Forming is hard to use for this alloy. It has high machinability. ElementContent (%)Aluminium / Aluminum, Al88.1Zinc, Zn6.8Magnesium, Mg2.7Copper, Cu2.0Chromium, Cr0.26
Properties PropertiesMetricDensity2.82 g/cm3Melting point482 °CElastic modulus70-80 GPaPoisson's ratio0.33Thermal expansion23.4 (10-6/°C)Ultimate Tensile Strength607 MPaTensile Yield Strength538 MPa
Designations Aluminium alloy 7178 alloy can be designated as:
ASTM B209 ASTM B221 ASTM B241 ASTM B316 QQ A-200/13 QQ A-200/14 QQ A-250/14 QQ A-250/21 QQ A-250/28 QQ A-430 SAE J454
Applications
Aircraft components Petroleum refineries Boilers Heat exchangers Condensers Pipelines Cooling towers Steam exhausts Electric generation plants
References
External links https://www.makeitfrom.com/material-properties/7178-T6-Aluminum https://www.substech.com/dokuwiki/doku.php?id=wrought_aluminum-zinc-magnesium_alloy_7178