Thermal aging and alloys
The alloy’s hardness will increase when aged at higher temperatures.
An alloy is a compound of two or more elements (metal or non-metal) chemically combined. An alloy produced from the combination of elements, may possess properties that are quite different from that of its constituent elements. Most of its properties like density, resistivity and thermal conductivity may be very different but they typically show significant improvements in physical such as shear strength and tensile strength.
During the manufacturing process of alloys, the period of aging and temperature will determine the initial hardness of the metal. The alloys can be given further heat treatment by aging them at high temperatures over time to increase their hardness and toughness.
Steel is an example of an alloy made from iron and carbon. The carbon used in steel acts as a hardening agent by helping to prevent the dislocation of the iron atoms from their crystal lattice. By adjusting the carbon content together with other alloying elements, steel that is stronger and harder than iron can be produced.
Ensure that the experiment is conducted in a properly equipped laboratory, under the supervision of your science teacher. Hot metal samples need to be handled with the use of proper equipment and protective gear.