Chemical materials are divided into metal materials and non-metal materials. Chemical metal materials can be divided into black metal materials and non-ferrous metal materials. Ferrous materials mainly refer to iron and steel, and most chemical machinery equipment is made of cast iron and carbon steel. High alloy iron, high alloy steel (such as high silicon iron, high nickel iron and various stainless steel), nickel, copper, aluminum, titanium, zirconium and their alloys are also widely used in chemical production. Non-metallic materials are widely used in the chemical industry, including plastics, rubber, glass, ceramics, enamel, impervious graphite and so on. Plastics develop rapidly, good corrosion resistance, the most widely used; Impervious graphite heat resistance, acid resistance, high thermal conductivity, large quantity; Ceramic and glass have good acid resistance, but they are brittle and cannot manufacture large equipment. Their use is limited, but they can be used for enamel, lining metal surfaces, enamel equipment, enamel (or lining) glass tanks, cans, etc.
      Between metal and non-metal, there is also an amorphous (state) alloy with a supercooled structure and strong corrosion resistance, some close to tantalum and precious metals, which is a development material.
      To take advantage of the advantages of different materials, a variety of composites have also been developed, including: metal and metal composites such as sandwich metal plates, with high strength, low corrosion resistance materials (such as carbon steel, aluminum alloy) as the base, and high corrosion resistance materials (such as pure aluminum, nickel, titanium, stainless steel, etc.). As a surface in contact with a corrosive medium. ② Nonmetallic and nonmetallic composite materials, such as reinforced plastics. ③ Non-metallic and metal composite materials, such as alloy ceramics, have a certain strength and high temperature resistance.