As a materials scientist with a focus on metallurgy, I am well-versed in the properties of various metals, including their thermal expansion. Thermal expansion is the phenomenon where a material expands when heated and contracts when cooled. This property is important in many engineering applications, as it can affect the fit and function of components in a system.

When comparing the thermal expansion of copper and aluminum, it's crucial to understand that different metals have different coefficients of thermal expansion. The coefficient of thermal expansion (CTE) is a measure of how much a material expands per degree of temperature change. It's usually expressed in units of length per degree Celsius (or Fahrenheit), such as µm/m·°C.

Copper has a relatively high coefficient of thermal expansion. Specifically, its CTE is approximately 16.6 µm/m·°C for pure copper. This means that for every degree Celsius that the temperature of copper increases, it expands by 16.6 micrometers per meter of its length.

Aluminum, on the other hand, has a slightly lower coefficient of thermal expansion compared to copper. The CTE for aluminum is around 23 µm/m·°C, which is higher than many other metals but less than that of copper.

Given these values, if we were to heat equal lengths of copper and aluminum by the same amount, the aluminum would expand more than the copper due to its higher CTE. However, it's important to note that the actual amount of expansion also depends on the initial length of the material and the temperature change.

The structure of the atoms in a material does play a role in its thermal expansion properties. Metals have a crystalline structure with atoms arranged in a regular pattern. When heat is applied, the atoms vibrate more vigorously, causing the lattice structure to expand. Copper and aluminum both have a face-centered cubic (FCC) structure, which is conducive to thermal expansion due to the relatively open arrangement of atoms.

In practical applications, engineers must consider the thermal expansion properties of materials to ensure that components fit together correctly and function as intended over a range of temperatures. For example, in the construction of bridges or large structures, the expansion and contraction of materials due to temperature changes must be taken into account to prevent warping or buckling.

In conclusion, while copper has a higher CTE than aluminum, it is the aluminum that would expand more under the same temperature increase due to its higher CTE value. However, the actual amount of expansion is dependent on various factors, including the initial length of the material and the specific temperature change.

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Transcript of Which Metal Expands The Most Copper, Aluminum, or Steal. ... My hypothesis was --If I add heat to copper, aluminum, and steal, then copper will expand the most, because when heat is added to the object it expands and the structure of the atoms also help--.Jan 13, 2015read more >>