| Bismuth | (english) Chemical symbol Bi. A soft, course cystalline heavy metal with a silvery white color and pinkish tinge; usually produced as a by-product of copper,leaad and other metals. Has a thermal conductivity lower than all other metals except mercury. Used as alloying agent but leading use is in pharmaceuticals. |
| Blast Cleaning (blasting) | (english) A process for cleaning or finishing metal objects by use of an air jet or centrifugal wheel that propels abrasive particles (grit, sand, or shot) against the surfaces of the workpiece at high velocity. |
| Blasting (Blast Cleaning) | (english) A process for cleaning or finishing metal objects by use of an air blast or centrifugal wheel that throws abrasive particles against the surface of the work pieces. Small, irregular particles of steel or iron are used as the abrasive in grit blasting, and steel or iron balls in shot blasting. |
| Bleeder | (english) A defect wherein a casting lacks completeness due to moltn metal draining or leaking out of some part of the mold cavity after pouraing has stopped. |
| Blister | (english) 1) Coating defect consisting of the formation of bubbles in a coating, which appear as hemispherical elevations. The blisters are hollow, and are usually caused by entrapped air or solvent. 2) A raised spot on the surface on the surface of metal due to expansion of gas which causes a subsurface metal separation such as inclusions and small laminations. |
| Blister 2 | (english) A defect in metal, on or near the surface, resulting from the expansion of gas in a subsurface zone. Very small blisters are called pinheads or pepper blisters. |
| Blowhole 2 | (english) A cavity which was produced during the solidification of metal by evolved gas, which in failing to escape is held in pockets. |
| Blue Annealing | (english) Heating hot rolled ferrous sheet in an open furnace to a temperature within the transformation range and then cooling in air, in order to soften the metal. The formation of a bluish oxide on the surface is incidental. |
| Blue Vitriol Copper sulfate | (english) A layout solution which turns a copper color when applied to a clean,polished metal surface. |
| Boil | (english) Agitation of a bath of metal caused by the liberation of a gas beneath its surface. May be deliberately induced by the addition of oxidizing material to a bath containing excess carbon. In the later case it is called a carbon boil and CO or CO2 are liberated. |