Glossary Terms

Mixture of concentrate and water prepared to restore depleted cutting fluid to its original state.

Hardening of a heat-treated material that occurs slowly at room temperature and more rapidly at higher temperatures. Usually follows rapid cooling or cold working.

Steel containing specified quantities of alloying elements (other than carbon and the commonly accepted amounts of manganese, sulfur and phosphorus) added to cause changes in the metal’s mechanical and/or physical properties. Principal alloying elements are nickel, chromium, molybdenum and silicon.

Element added to a metal to change its mechanical and/or physical properties.

Substances having metallic properties and being composed of two or more chemical elements of which at least one is a metal.

The body-centered cubic form of pure iron. Each of eight atoms is located in the corner of a cube, and one atom is located in the center of the cube. Alpha iron is stable below 1,670º F (910º C).

Formation of an aluminum or aluminum-alloy coating on a metal by hot dipping, hot spraying or diffusion.

Aluminum containing specified quantities of alloying elements added to obtain the necessary mechanical and physical properties. Aluminum alloys are divided into two categories: wrought compositions and casting compositions. Some compositions may contain up to 10 alloying elements, but only one or two are the main alloying elements, such as copper, manganese, silicon, magnesium, zinc or tin.

Aluminum oxide, also known as corundum, is used in grinding wheels. The chemical formula is Al2O3. Aluminum oxide is the base for ceramics, which are used in cutting tools for high-speed machining with light chip removal. Aluminum oxide is widely used as coating material applied to carbide substrates by chemical vapor deposition.

Not having a crystal structure; noncrystalline.

Determined by the position of the milling cutter’s centerline relative to the edge of the workpiece. Depending on the cutter diameter and the radial width of cut, the angle of entry can be negative or positive. A negative angle of entry occurs when the cutter’s centerline is located on the workpiece.

Solid adjustable or nonadjustable plate that holds work at a precise angle to the spindle during machining. Also used for inspection.