RE: How Strong is Aluminum?
aluhm > 12-20-2017, 06:02 AM
How strong aluminum is, depends on the specific alloy of aluminum, whether it is the aluminum 1000 series, or the 3000 series, or the 6000 series, or other variants. The 6000 series is most common for structural purposes. Do a search on its yield strength and its ultimate tensile strength, to get an idea of "how strong" your particular variant is.
The alloy Aluminum 6061-T6 has a yield strength of 35000 lb/in^2, and an ultimate tensile strength of 42000 lb/in^2. This is for the case of pure tension with a uniform load. The square inches refers to its cross sectional area. The ultimate strength occurs at the point where it will completely rupture. The yield strength occurs at the point, where it still supports the load, but ceases to be reversible after the load is removed.
Pure aluminum metal is much weaker than its alloys. It has a yield strength of about 1500 psi, and an ultimate strength of 10000 psi.
For structural purposes, you almost always want to stay below the yield strength.
How stiff aluminum is, is common among all alloys, as 10000000 psi. That is to say 10 million pounds of tension on an aluminum member with a cross sectional area of 1 inch, would hypothetically cause an increase equal to 1 length, if it were still in-tact and linear-elastic at that amount of stress. It isn't. A more realistic case, would be that 10000 pounds of tension on this member, would cause an 0.1% increase in length.