Understanding Controlled Expansion Alloys Controlled Expansion Alloys, also known as expansion alloys or thermal expansion alloys, are precision alloys with unique thermal expansion characteristics. These alloys are primarily composed of iron, nickel, and sometimes cobalt2, and are used in applications where the thermal size change of the metal must be considered in the design.Get more news about Controlled Expansion Alloy,you can vist our website! The alloys classified in this category include Alloy , Alloy 46, Alloy 48, Alloy 52, Kovar®, Invar®, and Super Invar3. These alloys are found in a broad variety of applications where thermal changes of a metal must be factored into the design of a component3. They are typically useful when forming a hermetic seal with glass or ceramic or when a specific expansion must be met over a certain temperature range. Alloy 42 is a controlled expansion alloy consisting of 41% nominal nickel, balance iron. It is used in a wide variety of electronic applications, lead frames, especially for glass and ceramic seals3. Alloy 46 contains 46% nickel with the balance iron and is used in applications that require glass and ceramic seals. Alloy 48 consists of approximately 48% nickel and the balance iron. This binary nickel-iron alloy is applicable to a wide variety of electronic applications that require a low coefficient of expansion at 400°C for glass-to-metal seals in soft lead or soda lime glasses. Alloy 52 is another controlled expansion alloy consisting of 50.5% nominal nickel, balance iron; used in a wide variety of electronic applications especially for glass seals3. Invar® is a low expansion alloy consisting of nominal 36% nickel; balance iron. This controlled expansion alloy is known for its rate of thermal expansion that is approximately one-tenth of carbon steel at ambient temperatures up to 400°F3. These characteristics have made these alloys contenders for many applications where dimensional changes due to temperature variations must be minimized. With more than 160 years materials expertise, companies like Sandvik provide tailor-made components made from Osprey® controlled expansion (CE) alloys. In conclusion, Controlled Expansion Alloys play an essential role in various industries due to their unique thermal expansion properties. Their use in electronic applications and their ability to form hermetic seals with glass or ceramic make them invaluable in today’s technology-driven world.