What does LMIE mean in MISCELLANEOUS

Liquid-Metal-Induced Embrittlement (LMIE) is a form of environmental degradation that occurs when two different metallic materials are coupled together and exposed to certain types of liquid metals. The result is reduced ductility and strength leading to embrittlement and eventual failure.

The main effect of LMIE is reduced ductility and strength leading to embrittlement and eventual failure due to hydrogen absorption into the material's surface. This can lead to cracking, reduced fracture toughness, localized corrosion, or even complete material failure at its operating temperatures.

One way to prevent LMIE is through proper design considerations such as using contact surface materials with similar galvanic potentials or by coating one material with another such as epoxy or aluminum oxide coatings to separate them electrically and eliminate galvanic coupling. Proper maintenance such as regular cleaning and inspection should also be done to detect any signs of corrosion early on and mitigate its effects.

When working with piezoelectric components in a system, it's important to ensure there won't be any galvanic coupling between them which could lead to LMIE. This can be done by using contact surface materials with similar galvanic potentials or coatings such as epoxy or aluminum oxide layers to separate them electrically.

While other forms of environmental degradation mainly affect the material's external surfaces, LMIE affects an entire component due to its internal processes including hydrogen absorption into the material's surface which results in embrittlement in both components involved in the galvanic coupling process.