ASTM B254-92(2020)e1

Kategorie - podobné normy:

Vysokokvalitní oceli

Anotace textu normy ASTM B254-92(2020)e1 :

This practice covers the preparation and electroplating of metals on stainless steel. The preparation of stainless steel for electroplating involves three basic steps in the following order: removal of scale, removal of oil, grease, or other foreign material by cleaning, and activation immediately before electroplating. Activation shall be done by removing the thin transparent film of oxides from the surface to be electroplated. This film will reform if the parts are allowed to dry or are exposed to oxygen-containing solutions. For this reason, the shortest interval practicable should elapse between the time the parts are removed from the activating solution and covered by the electrodeposit, unless a simultaneous activation-electroplating procedure is used. The parts should be transferred to the cold-water rinse and to the plating solution as rapidly as practicable after the activating procedure; otherwise the surface will passivate itself and the electrodeposit will not be adherent. The rinse water should be kept slightly acid. After activation, an adherent electrodeposit of commonly electroplated metals like cadmium, copper, brass, chromium, gold, nickel, or silver may be electrodeposited directly on stainless steel provided the surface of the stainless steel. After stripping with nitric acid, post electroplating operations such as stress relieving, buffing or coloring, and forming or drawing may be applied to stainless steel in the same manner as to any other basis metal, as long as the natural differences in the characteristic of the stainless steel are taken into consideration. The methods of testing for thickness, hardness, and adhesion of electrodeposits applied with the usual basis metals may be employed for similar tests on stainless steel.

Keywords:

ICS Number Code 77.140.20 (Steels of high quality)