000 01892nab a2200181 4500
005 20260520001103.0
008 260224s2012 xxu
245 0 0 _aLocalized corrosion of binary mg-nd alloys in chloride-containing electrolyte using a scanning vibrating electrode technique
260 _a
_b
_cjun. 2012
270 _a06/09/2012 ; 06/09/2012
300 _a10 p. ; 489-498
520 _aThe influence of neodymium (Nd) alloying additions in the 0.47 wt% to 3.53 wt% range on the localized corrosion behavior of Mg, when freely corroding in aqueous sodium chloride (NaCl) electrolyte, is investigated using an in situ scanning vibrating electrode technique (SVET). For all samples, the point of surface breakdown is an intense focal anode that expands radially with respect to time, revealing a cathodically activated interior, which is galvanically coupled with the local anode at the perimeter. However, for Nd compositions of =0.74%, radial expansion ceases within ca. 2 h of initiation, whereupon dark filiform-like corrosion features are observed, which traverse over the exposed Mg surface. For Nd additions of =1.25%, the radial expansion continues with time up to a point where the entire intact surface becomes consumed. The intensity of the local anode ring of circular corroded regions is seen to increase as more cathodically activated corroded surface becomes exposed. Mean current density values measured within these corroded areas increase progressively with Nd content, leading to a progressive rise in localized corrosion rates. The cathodic activation of corroded regions is proposed to derive from an enrichment of noble, Nd-rich intermetallic grains caused as the alpha-Mg phase becomes attacked at local anode sites.
581 _a6
773 0 _tCorrosion
_g68
942 _cARTICULO
100 1 _aWilliams, G.
_927474
999 _c187299
_d187299