Scab - A defect on the ingot caused by metal which splashes during teeming; on rolled or forged products it appears as a silver-like defect partially welded or mechanically bound to the parent metal surface.
Scale - An iron oxide formed on the surface of hot steel, sometimes in the form of large sheets which fall off when the steel is rolled.
Scleroscope or Shore Hardness Test - This test consists of dropping a small diamond tipped hammer from a standard height onto the surface of the specimen being tested. The height to which the hammer rebounds is a measure of the surface hardness of the specimen.
Screw Stock - Metal in the form of a wire or rod, ordinarily a free machining type, used for making screw machine products.
Seam - An elongated discontinuity in metal caused by blowhole or other defect which has been closed by rolling or forging mechanically but not welded.
Semi-Killed Steel - Characterized by variable degrees of uniformity and compositions and have properties intermediate between those of killed and rimmed steels.
Shear Strength - The stress required to produce a fracture in the plane of a cross-section, the conditions of loading being such that the directions of force and of resistance are parallel and opposite although their paths are offset a specified minimum amount.
Sherardizing - A cementation process used to give small steel articles, such as bolts, a corrosion resistant surface of zinc-rich alloy. The articles are packed with zinc dust in drums which are heated for several hours while slowly rotating.
Shortness - Brittleness.
Silky Fracture - A steel fracture having a very smooth, fine grain, or silky appearance.
Skelp- Steel or iron plate from which pipe or tubing is made.
Sketch Plates - Plates cut to shapes other than rectangular.
Slab - A thick rectangular piece of steel for rolling down into plates.
Slabbing Mill - A mill for rolling slabs from ingots.
Slag - A result of the action of a flux on non-metallic constituents of a processed ore, or on the oxidized metallic constituents that are undesirable. Usually consist of combinations of acid oxides and basic oxides with neutral oxides added to aid fusibility.
Slip Bands - A series of parallel lines running across a crystalline grain. Slip bans are formed when the elastic limit is passed by one layer or portion of the crystal slipping over another portion along a plane, known as the slip plane.
Soaking - Holding steel at a predetermined temperature for a sufficient time to assure heat penetration and/or to complete the solution of carbides.
Solid Solution - A condition wherein one element is dissolved in another element while the dissolving element is in a solid and not liquid condition.
Solidification Range - The temperature range through which metal freezes or solidifies.
Sonims - Solid non-metallic inclusions in metal.
Spalling - Cracking and flaking of a metal surface.
Special Killed Steels - Low-carbon aluminum-killed steels mainly used for extra deep drawing sheet and strip.
Special Quality - Produced for applications involving forging, heat-treating, cold drawing, machining, etc. Special quality bars are furnished in standard, other than standard, or restricted chemical grades, or to mechanical property specifications. This quality is subject to variations in check analysis.
Spiegel (or Spiegeleisen) - A pig iron containing 15% to 30% manganese and 4.5% to 5.5% carbon.
Spot Welding - Electric-resistance welding in which fusion is limited to a small area directly between the electrode tips.
Static Load - A load which is sustained without motion-such as weight hanging on a string.
Step Down Test - A sample of steel is machined down to different diameters and inspected at different distances from the surface.
Stress - The load per unit area tending to deform a material.
Stress Relieving - Reducing residual stresses in a metal by heating to a suitable temperature for a certain time. This method relieves stresses caused by casting, quenching, normalizing, machining, cold working or welding.
Stretcher Leveling - A method of producing unusual flatness in steel sheets by stretching them in a hydraulic device.
Stretcher Strains - These are vein-like surface defects which may appear in low carbon steel during cold deformation. They are associated with the irregular moment of the metal when it is being strained at the yield point. Stretcher strains are also known as "Luder's lines", "strain figures", etc.
Swaging - Shaping metal by causing it to flow in a swage by pressing, rolling or hammering (also called swedging).
Sweep - In reference to wide flange beams, sweep is the curvature from the plane of the web in the length of the beam.