BS EN 12330:2000 – Corrosion protection of metals一 Electrodeposited coatings of cadmium on iron or steel
7 Requirements
7.1 General All tests (including corrosion rsistance test) shall be deferred until the expiy ofa period of 24 h alter the chromating process has ended. NOTE Chromase conversion comigs harden wth age by gradual dehydration They should theretore be handed caretully lor the tirst 24 h ather the treatmnent.
7.2 Appearance Over the signicant sutace, the electroplated articles shall be free from clearty isible plating detects such as blisters, pits, roughness, racks or unplated areas. See also 4.1 d) of EN 1403:1998. Parts which have been given supplementary treatment shall be froe from urtreated areas on he significant surtace.
7.3 Thickness 73.1 Minimum local thickness When tested in accordance with one of the tllowing standards the minimum local thickness of the cadmium coating on artides havng a sindicant surface of grealer than 1 cm? shall contorm to hat spedied in its designation: EN IS0 1463. EN iso 2177, EN IS0 217B. EN ISO 2360, prEN IS0 3497. prEN ISO 3543.
NOTE_ Betore using the mthad specied in EN ISO 2177.Bs ncessary, to remove the chromate or gther supplementary treatment using a very mild abrasive, for example a paste of levigated alumina or magnesum oxlde. In the case of heavy conversion catigs. the rsuts wll therelore be sighty low. 32 Average thicknes For articles having a significant surtace of less than 100 mm, the minimum local thickness shall be deemed 1o be the mirimum value of the average determined by the method specilied in Annex D.
7.4 Adhesion
7.4.1 Adhe sion of cadmium coating When tested by the burnishing test in accordance with EN ISO 2819 the cadmium coating shall have good adhesion.
7.42 Adhesion of coloured chromate coatings Coloured chromale coatings shall be tested in accordance with 3.6 of EN ISO 3613:1994.
7.5 Corrosion resistance When tested in accordance with the neutral salt spray (NSS) lest described in ISO 9227 ftor the times given in Tables 1 and 2, the test surface shall remain free trom red crrosion product whien examined by the unalded eye or corected wsion. Sight staining of the test surtace shall not be a cause of rejection. The test surface shall comprise those parts of the significant surfaces of the test specimens that can be touchedby a ball 20 mm in diameter or as otherwise specied by he purchaser (s00 Clause 4) NOTE Red corrosion ind caiese corrosion of the basis metal.
BS EN 12330:2000 – Corrosion protection of metals一 Electrodeposited coatings of cadmium on iron or steel