Aichs metal, also known as Aich's alloy, is a type of low-melting-point fusible alloy that is primarily composed of tin, bismuth, and lead. The specific composition may vary, but the most common formulation typically contains approximately 50% tin, 25% bismuth, and 25% lead. It is named after Carl Friedrich Aich, a German chemist who developed this alloy in the early 19th century.
Due to its low melting point, Aichs metal is often used in various applications that involve low-temperature soldering, brazing, or casting. One of its notable properties is its eutectic behavior, meaning that its components melt and solidify at the same temperature, resulting in a sharp melting point. This characteristic makes it particularly useful in electrical applications, such as fuses and electrical connectors, as the alloy can easily melt when subjected to excessive heat or current overload, thereby protecting the electrical circuit from damage.
Aichs metal is also commonly utilized as a safety device in fire sprinkler systems. Within these systems, Aichs metal acts as a heat-activated trigger mechanism, melting and triggering the release of water when exposed to high temperatures, such as in the event of a fire.
Despite its advantageous properties, Aichs metal does have some limitations, including its relatively low strength and corrosion resistance. These factors often restrict its use to applications where the operating conditions are not highly demanding.
