Chemical Composition - Major Components

• Aluminum is the main component of this alloy and it makes up 87.1 to 91.4 percent of the entire composition of Aluminum 7075. Zinc is the second most prevalent ingredient at 5.1 percent to 6.1 percent. Chromium comprises 0.18 to 0.28 percent of the alloy, magnesium accounts for 2.1 to 2.9 percent and there is 1.2 to 2 percent copper included in its formula.
  
  

Chemical Composition - Additional Components

• Silicon is found in the alloy at a maximum concentration of 0.4 percent and manganese is present at 0.3 percent. There is up to 0.2 percent titanium in Aluminum 7075 along with up to 0.5 percent iron. Up to 0.15 percent of miscellaneous metals and minerals are allowed according to specifications, so long as no one other ingredient exceeds 0.5 percent of the total composition.
  
  

Physical Properties

• The density of aluminum 7075 is 0.101 lbs. per cubic inch and its specific gravity is 2.81. It melts at 900 degrees Fahrenheit, although that figure increases to as much as 1,175 degrees depending on thickness and processing techniques. Its modulus of elasticity tension (resistance to pulling force) is 10,400 kilopounds per square inch and its modulus of elasticity torsion (resistance to twisting force) is 3,800 kilopounds per square inch. The shear strength of this alloy is 48,000 pounds per square inch.
  
  

Strength

• Its hardness number on the Brinell scale is 150 and this converts to 191 on the Knoop scale, 53.50 on the Rockwell A scale, 87 on the Rockwell B scale and 175 on the Vickers scale. The ultimate tensile strength of aluminum 7075 is 83,000 pounds per square inch and its tensile yield strength is 73,000 pounds per square inch. The fatigue strength of this form of aluminum is measured at 23,000 psi and its minimum fracture toughness is 18.2 kilopounds per square inch.
  
  

Additional Specifications

• The electrical resistance of aluminum 7075 is rated at 2.028944E-06 ohms per inch and its heat conductivity is 13.1 microinches per inch per degree Fahrenheit. Its machinability is assessed at 70 percent and its annealing (heat treatment before machining) temperature is 775 degrees Fahrenheit. The solution temperature of this metal product is 870 to 900 degrees Fahrenheit and its aging temperature is 250 degrees Fahrenheit. The material remains solid at temperatures up to 890 degrees Fahrenheit and becomes fully liquid at 1,175 degrees Fahrenheit.