“SBQ” is generally used in the USA, while in Europe the term “engineering steels” is more common. Both terms refer to Steel types as well as to bar products, and as they are often associated with the steel grades, they refer to billet and slab as well as bar.

The superior mechanical properties and defect-free surface of SBQ make it indispensable in the manufacture of components – often safety-critical components – that are in motion. Applications include gears, shafts, axles, drive trains and suspensions for automobiles, off-highway vehicles and industrial capital equipment, plus some components for aerospace and oil drilling.

References: http://www.metalbulletin.com/Article/1448055/SBQ-steel.html

At Walker Forge we order millions of pounds of Special Bar Quality (SBQ) steel every week from a select group of approved mills as the first step to ensuring our customers receive only the highest quality forgings. Raw material is selected to match the capability of the mill with the end use of the product. The chemistry is verified to each heat of steel to ensure it meets customer specifications.
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