Ferrous materials used in a passenger car have been reduced from 81 percent to 71 percent in these 20 years. Consumption ratio of high strength steel (HSS) is now 30-40 percent in a passenger car. Outer panel of car body is produced with rephosphorized steel having 340-390 MPa tensile strength (TS) in which door and trunk lid are produced with BH steel. TRIP steel is attracting a wide attention by an excellent balance between strength and elongation or fatigue property. Continuous annealing technology plays an important role for producing excellent HSS. Production ratio between hot dip and electrolytic zinc coating is approximately 65 percent and 35 percent, where galvannealed steel and Zn-Ni coated one with organic film became popular. Noise dumping steel with polyester film at the central layer has been developed and used for oil-pan, cylinder head cover and dash panel. Stainless steel is used for exhaust manifold at about 25 percent and for the parts between front and tail pipe at about 100 percent. As forged steel eliminating post heat treatment showed approximately 13 percent in consumption of special steel, in which the steel having 900-1,000 MPa TS is used. A new technology called Oxide Metallurgy is effectively applied for producing very fine structure after forging. Various free cutting steels containing pb, S and Ca are used.
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