| Acetyl Tributyl Citrate | (english) One of the lubricating oils generally applied on tin Mill Products (tin plate, TFS-chrome/chrome oxide coated steel, and blackplate). |
| Acid | (english) 1) A solution or liquid with a pH less than 7, 2) term applied to slags, refractors, and minerals containing a high percentage of silica. |
| Acid Brittleness (Pickling Brittleness) | (english) Brittleness resulting from pickling steel in acid; hydrogen, formed by the interaction between iron and acid, is partially absorbed by the metal, causing acid brittleness. |
| Acid Process 1 | (english) A process of making steel, either Bessemer, open-hearth or electric, in which the furnace is lined with a siliceous refractory and for which low phosphorus pig iron is required as this element is not removed. |
| Acid Process 2 | (english) A steel making method using an acid refractory-lined (usually silica) furnace. Neither sulfur or phosphorus is removed. |
| Acid Steel | (english) Steel melted in a furnace with an acid bottom and lining and under a slag containing an excess of an acid substance such as silica. |
| Acid-Brittleness | (english) Brittleness resulting from pickling steel in acid; hydrogen, formed by the interaction between iron and acid, is partially absorbed by the metal, causing acid brittleness. |
| Acid-Process | (english) A process of making steel, either Bessemer, open-hearth or electric, in which the furnace is lined with a siliceous refractory and for which low phosphorus pig iron is required as this element is not removed. |
| Acme Thread | (english) A screw thread having a 29 degree included angel. Used largely for feed and adjusting screws on machine tools. |
| Activation | (english) The changing of the passive surface of a metal to a chemically active state. Contrast with passivation. |