Physical and mechanical property changes that occur in low carbon steel that is stored over time. Exposure to elevated temperatures can speed the effects of aging.
The process used to soften cold rolled steel to make it more formable. Accomplished through heating and cooling of the rolled steel.
The measurement of deviation between a concave side and a straight line.
Carbon Steel - Steel exhibiting properties derived mainly from carbon with only minimal amounts of other alloying elements. Also known as straight carbon steel or plain carbon steel.
Coil Breaks -
Creases or ridges in that appear as parallel lines across the direction of rolling. Typically extending the full width of the sheet or strip. Also known as Lüder's Lines.
Cold Rolled Products -Hot rolled steel that has been rolled to its specified final thickness at room temperature.
Commercial Steel (CS) -Steel that can bend or be moderately formed. Commercial Steel can be bent flat upon itself in any direction at room temperature.
Gradual chemical or electrochemical attack on a metal by atmospheric moisture or other agents.
Critical Surface -A prime side surface that is free of repetitive type imperfections, gouges, scratches, scale and slivers.
Cut Edge -
Removal of the hot mill edge. Coil ends are cropped back to gauge when cut edge is ordered.
Cut to Length - When a specific or discrete length is specified.
Deep Drawing - The process of working metal blanks in dies on a press into shapes which are usually more or less cup-like in character.
Drawing Steel (DS) -Steel which has a greater degree of ductility and is more consistent in performance than Commercial Steel because of higher standards in production, selection and melting of the steel.
Deep Drawing Steel (DDS) -This steel should be used when Drawing Steel will not provide a sufficient degree of ductility for fabrication of parts having stringent drawing requirements, or applications that require the sheet be free from aging. This quality is made by special steelmaking and finishing practices.
Dent Resistant - BH Series -
Steel produced from partially stabilized steel that offers a unique combination of formability and final properties after fabrication. This steel combines strength and high formability. Although this steel is non-aging at room temperature, it gains strength from work-hardening during fabrication and from carbon-aging during paint-baking. (Sometimes referred to as "bake hardenable.")
Extra Deep Drawing Steel -
Steel that has superior formability and excellent uniformity. Having a very low carbon content with stabilizing elements added to make it interstitial free. It is a non-aging steel with high resistance to thinning during drawing and is suitable for critical forming applications.
DS Type B Steel -Steel intended for applications that require particularly severe drawing and forming.
Ductility - The ability to permit change of shape without fracture. In flat rolled steel, ductility is usually measured by hardness or mechanical properties in a tensile test.
Elongation - The percent increase of a given distance prior to fracture during tensile testing.
Embossed sheet - An embossed sheet is one having a prominent, impressed texture or pattern on its surface(s). If the defined texture is applied to the surface only, it is most properly termed a coined surface. If the texture or pattern carries through the entire body of the sheet and appears on both surfaces it is a true embossed sheet.
Extra Smooth Galvanized - An Extra Smooth finish is imparted to hot-dip metallic-coated steel sheet by temper rolling after coating to decrease the surface relief that occurs when the molten coating solidifies. The spangle pattern (grain pattern) is made distinctly less visible by the matte finish imparted by the rolling operation. Most Extra Smooth sheet is intended for either prepainted or post-painted applications.
Flatness - Flatness is a measure of a cut length sheet's ability to conform to a flat horizontal surface. Maximum deviation from that surface is the degree to which the sheet is out of flat. Flatness is often expressed quantitatively in either Steepness or I-Units. For Hardened and Tempered products flatness is measured as a deviation in thousands of an inch per inch of width.
Resistance of metal to penetration of the surface.
High Strength - Product intended for applications where greater strength is critical. High Strength typically begins at 35 ksi minimum yield strength.
High Strength Low Alloy (HSLA) - A specific group of steels in which the strength levels are achieved by the addition of moderate amounts of alloying elements. The most common are columbium, vanadium or titanium.
Hot Rolled Sheet - Steel sheet that is processed to its final thickness by rolling at high temperatures on a specially designed hot-rolling facility.
Hot Rolled Sheet Non-Temper Rolled - A U. S. Steel definition for product supplied as a coil directly off the Hot Strip Mill with no additional processing.
Leveling - Flattening of rolled sheet by reducing or eliminating distortions.
Lüder's Lines -
Creases or ridges in sheet that appear as parallel lines across the direction of rolling, and that generally extend the full width of the sheet or strip. Also referred to as Lüder's Lines.
Matte Finish - A more uniform surface finish imparted to the sheet surface by temper rolling with shot-blasted rolls.
Mechanical Properties - The properties of a material that reveal its elastic and inelastic behavior when force is applied, thereby indicating its suitability for mechanical applications.
Applied after pickling or temper rolling to assist customer handling by minimizing inter-wrap gouging, improve lubricity and provide a more rust resistant product.
Removing surface oxides from metals by a chemical reaction.
Prelubricant - An oil coating that is applied to steel sheet to enhance formability (deep drawing). This lubricant is usually applied when the customer wishes to avoid the application of a forming lubricant in his plant.
Roll Forming -
A fabrication process whereby the metal sheet is deformed continuously in a linear manner by passing it through a consecutive series of rolls which produce a predetermined profile in it.
When two or more widths are obtained from the hot rolled substrate width. The slitting operation results in a cut edge.
Spangle- The spangle of a hot-dip coated sheet surface is the visual manifestation of the grains that form within the coating when it solidifies as the sheet emerges from the pot of molten coating metal. The spangle or grain varies in size, brightness and surface relief, depending upon a number of factors, most of which are related to the composition of the coating and cooling practices.
Structural Steel- When this term is applied to steel sheet, it refers to the designation that is used for steel sheet that is produced to meet a specific level of strength and formability. The formability is expressed as percent elongation in a tensile test. Structural Steel is typically used for applications where the strength of the sheet is an important design criterion, i.e., load-bearing applications.
Tension Leveling- A mechanical operation wherein steel sheet, in coil form, is processed on a unit that stretches the product beyond its yield point to impart permanent deformation. The stretching operation assists to flatten the sheet. Tension leveling is considered the optimum process to achieve superior flatness characteristics.
Temper Rolling - A light cold reduction of the sheet steel. This operation is performed to improve flatness, eliminate discontinuous yielding and to obtain a uniform surface.
Tensile Strength - The maximum stress that a material can withstand. In tensile testing, the ratio of maximum load to original cross sectional area. Also called Ultimate Strength.
A term that is used to quantify the allowable deviation from a dimension. For example, tolerances exist for the sheet thickness, width, flatness, camber, etc.
The load or stress at which a marked increase in the deformation of the sheet occurs without increasing the applied load. Yield point is one of the characteristics of low-carbon steels after they have been annealed. The yield point is usually calculated using a tensile-test specimen, and it is the load that is commensurate with the point beyond the elastic limit at which the specimen lengthens considerably without an additional increase in load.
Yield Strength- The stress at which a material exhibits a specified deviation from a linear proportionality between load and elongation. In the tension test, the load associated with an offset of 0.2% from linearity is used for many metals to calculate the yield strength.