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. |
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. |
Blocker |
(english) Preform die or impression, used when part cannot be made in a single operation. |
Blow Back |
(english) A coating defect consisting of a lower coating film weight on the bottom of the coated sheet caused by high velocity air in the oven. Blow back usually occurs with high solids coatings which have little solvent to evaporate and "set" the film. |
Blue Print |
(english) A pen or ink line drawing reproduced (printed) on sensitized paper by direct exposure. |
Blush |
(english) A coating defect consisting of the whitening of a cured film which results in a translucent or opaque appearance with accompanying loss of gloss. Blushing usually occurs during the pasteurization or steam processing of films which are undercured or water sensitive. |
Bolster (die block) |
(english) A “tool” or reinforcing part which supports the backer-which, in turn, supports an extruding die against the pressure of extrusion. |
Bottom Up |
(english) Reversing the wrap of a coil putting the top surface on the bottom. |
Box Annealing 2 |
(english) A process of annealing a ferrous alloy in a closed metal container, with or without packing materials, in order to minimize the effects of oxidation. The charge is normally heated slowly to a temperature below the transformation range, but occasionally above or within it, and then is slowly cooled. |