ATI (formerly known as Allegheny Technologies) is a company that manufactures and supplies specialty materials and complex components. It operates through two segments: High Performance Materials & Components (HPMC) and Advanced Alloys & Solutions (AA&S). The HPMC segment provides materials and components. The AA&S segment produces flat-rolled products. The company provides machining, finishing, and fabrication services. ATI caters to aerospace, defense, energy, medical, and other sectors.