The heat transfer through a piece of metal is typically referred to as "conduction." Conduction is one of the three primary modes of heat transfer, alongside convection and radiation.
In the context of heat transfer in solids, such as a metal, conduction occurs when thermal energy is transferred from one part of the material to another through direct molecular interactions. Within the metal, the atoms or molecules vibrate and collide with each other, transferring kinetic energy from the hotter regions to the cooler regions.
In the case of a piece of metal being heated at one end, conduction enables the transfer of heat from the hot end to the colder end, as the thermal energy is conducted through the metal's structure. This process continues until the temperature throughout the metal reaches equilibrium.
Conduction is a significant mode of heat transfer in metals due to their high thermal conductivity, which is a measure of a material's ability to conduct heat. Metals, such as copper or aluminum, are known for their good thermal conductivity, making them efficient conductors of heat.