Page 631 - Automotive Engineering Powertrain Chassis System and Vehicle Body

Materials for consideration and use in automotive body structures C HAPTER 18.2

Strength and deformability of steels
produced by various methods
Strength
CA-DP
Al ru = aluminium-killed steel
BA = batch annealing
DKG
HSLA BH = bake hardening
CA = continuous annealing
P CA-BH DKG = double cold-reduced
DP = dual phase
HSLA = high strength low
alloy
CA
IF = interstitial free steel
P = phosphor steel
BA
Ingot steel
IF
Aluminium-killed steel
Deformability
Fig. 18.2-1 Range of flat rolled steel products. (Courtesy of Corus.)

manufacture has been smelted from iron (produced in forming grades specified in Euronorm EN 10130.
the blast furnace) and recycled scrap. Basic Oxygen Normally these steels are aluminium killed (AK), an
Steelmaking (BOS) is the normal route whereby impu- aluminium addition minimizing ageing effects by com-
rities are oxidized by the injection of oxygen through bining with nitrogen, and forming the characteristic
the bottom of the converter (included in Fig. 18.2-2), to ‘pancake shaped’, i.e. elongated, grains evident in the
produce refined material of composition typical of microstructure. Carbon levels are typically 0.03–0.05

Steel
production
process

Fig. 18.2-2 (a) Typical sheet metal steel manufacturing process.

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