Aluminum-Iron-Silicon Interphase Control

Aluminum-iron-silicon interphases are the interfaces between these elements in the microstructure. If you don't control them, you'll get hard, brittle phases that mess up welding and component durability. You have to adjust the alloy so that a homogeneous structure forms without too much of these brittle compounds precipitating. Adjust the melt guidance and the additions of iron and silicon accordingly, then the part stays deformable and weldable.