Does metal get stronger with age?

Metal aging is used to solution heat treat alloys to increase their strength and hardness while reducing their ductility. This can be done naturally - simply by letting the metal alloy hang for years - or artificially.

As metal ages, it forms metal precipitates with the help of supersaturated alloying elements. These block dislocations in the metal make it stronger, harder, and less ductile. Artificial metal aging is accomplished by heating a solution heat treated alloy. The temperature must be below the recrystallization point but high enough to form a precipitate more quickly. Once the precipitate reaches the appropriate size, the metal cools rapidly to prevent further expansion.

Which metals can be aged?

As long as the metal alloy is solution heat treatable, it can be aged. The most popular options include stainless steel, aluminum, copper and other metal alloys. All of these alloys have the ability to become extremely hard and strong as they age. Even copper, which is usually soft and ductile, can be transformed through the metal aging process. It becomes harder and stronger, but also very fragile. You should also be able to age magnesium, nickel, and titanium as long as those alloys are solution heat treatable.

Can metal age excessively?

It's entirely possible for metal to age excessively. If the metal is machined beyond the ideal precipitate size, the resulting alloy will actually reduce its strength and hardness. This can happen when you try to weld or cold work an alloy. This can also occur if the metal is heated beyond the target precipitate size. You may be able to artificially age the metal again, which can restore its strength and hardness, but it's wise to consult a metallurgist before making any decisions.

How do I know if my metal should be aged?

If you have a metal project where the parts need to be strong, hard, and less ductile, then metal aging in Gastonia, NC may be the process for you. However, there are other processes that can achieve similar results. For example, flame and induction hardening, annealing, and quenching are all methods metallurgists use to harden metals. The correct process depends on the type of metal you are working with, your end goals, and the recommendations of your metallurgist.