What are the two principal classifications of alloys?

• A. Ferrous and nonferrous
• B. Metals and ceramics
• C. Casting alloys and wrought alloys
• D. Primary and secondary

Answer: (C)

Processing method is what this question highlights: alloys are commonly classified by how they are formed, into castings and wrought forms. Casting alloys are designed to be melted and poured into a mold to take shape, which allows complex geometries and typically lower-cost production. Wrought alloys are shaped after solidification through mechanical deformation—rolling, extrusion, drawing, or forging—resulting in a refined grain structure and enhanced strength and ductility. This distinction matters in aviation practices because it influences fabrication methods, heat treatment options, and corrosion behavior. While ferrous versus nonferrous categorizes metals by iron content, and the other options mix material type or production stage, casting versus wrought is the practical, processing-based split used for alloys.