1. Metal materials can be generally divided into ferrous metals and non-ferrous metals. Ferrous metal: Iron-based metal with black color is called ferrous metal, such as cast iron, and steel is ferrous metal. Nonferrous metals: Nonferrous metals, such as copper, aluminum, tin, lead, zinc and other metals. 2. According to the following five points on the iron-carbon phase diagram, iron-carbon alloys can be divided into seven categories, namely: point P [w(c)=0.02 18%], point S [w(c)=0.77%] and point E [w (c) = 2.160. 1) Steel and iron are generally distinguished by carbon content and carbon content.