Oil Stain Aluminum Stain produced by the incomplete burning of the lubricants on the surface of the sheet. Rolling subsequent to staining will change color from darker browns to lighter browns down to white. Oil-Hardening Steel Steel adaptable to hardening by heat treatment and quenching in oil. Test A method of measuring the ductility and drawing properties of strip or sheet metal which involves determination of the width and depth of impression. The test simulating a deep drawing operation is made by a standard steel ball under pressure, continuing until the cup formed from the metal sample fractures.
Readings are in thousandths of an inch.
This test is sometimes used to detect stretcher straining and indicates the surface finish after drawing, similar to the Erichsen ductility test. Open Surface Rough surface on black plate, sheet or strip, resulting from imperfection in the original steel bars from which the plate was rolled. Open-Hearth Furnace A reverberatory melting furnace with a shallow hearth and a low roof. The flame passes over the charge in the hearth, causing the charge to be heated both by direct flame and radiation from the roof and sidewalls of the furnace. In ferrous industry, the furnace is regenerative.