内容
Introduction
The thermal expansion of metals is a phenomenon whereby metals, upon exposure to an increase in temperature, increase in length, generally much greater than other materials. The rate at which a metal expands and contracts with changes in temperature is commonly referred to as its coefficient of thermal expansion (CTE), and different metals have different CTEs. This paper will review the thermal expansion of non-ferrous alloys and their associated coefficients of thermal expansion.
Thermal Expansion of Non-Ferrous Alloys
Non-ferrous alloys are defined as alloys that lack iron as their primary element. These alloys are usually lighter, more malleable and resistant to the elements than ferrous alloys, and have many different properties that make them useful in a variety of industries. For example, certain non-ferrous alloys can be used for high temperature applications, electrical insulation and corrosion resistance in seawater.
Thermal expansion is defined as the increase in length of a material when it is heated. The amount of expansion is directly related to the CTD of the material, which is a measure of how much it expands or contracts in response to a variation in temperature. Non-ferrous alloys generally have higher coefficients of thermal expansion than ferrous alloys. This property is of importance in many applications. For example, if a part made of a non-ferrous alloy expands more than another part of a machine when heated, the two parts will become misaligned as the temperature fluctuates.
The coefficient of thermal expansion of non-ferrous alloys can vary significantly depending on the alloy system and other factors such as its composition, temperature, and aging. Aluminum alloys, for example, have an average CTE of 24*10-6K-1, while copper alloys can have a CTE that ranges from 16*10-6K-1 to 22*10-6K-1. The CTE for zinc alloys can range from 20* 10-6K-1 to 40*10-6K-1, depending on the zinc-base alloy system.
Conclusion
Non-ferrous alloys are materials that contain little to no iron. These materials can have significantly different thermal expansion coefficients based on the alloy system and composition. The amount of thermal expansion an alloy experiences can be used to create parts that will remain dimensionally stable in different temperature ranges. This property is highly desirable in many industries, such as the automotive and aerospace industries, where heat and pressure changes can lead to misalignment of components. It is important to consider the CTE of non-ferrous alloys when designing products since its expansion rate can be drastically different than that of other metals.
