TY - JOUR A1 - Valet, Svenja A1 - Burkert, Andreas A1 - Ebell, Gino A1 - Babutzka, Martin T1 - Determination of the corrosion product layer resistance on zinc and electrolytically galvanized steel samples by using gel electrolytes T2 - Electrochimica Acta N2 - Although zinc and zinc coatings have been widely used for corrosion protection for decades new zinc coatings are constantly being developed. Characterizing the corrosion protectiveness of these new coatings, however, should not be underestimated. While exposure tests are time intensive, cyclic tests can only be used for a very limited field of application. Thus, electrochemical measurements provide both an efficient and an effective alternative. Conventional aqueous bulk electrolytes influence the surface layers of a tested zinc coating and are therefore not reliable. Gel electrolytes, however, have evolved over the last few years, are minimally invasive and provide reliable results. This work describes experiments with gel electrolytes made of agar. Unlike previous work, it proposes a composition of gel electrolyte for minimally invasive description of the protective power of naturally formed oxide layers on zinc and zinc coatings. Therefore, as a first part, the gel electrolyte made of agar is verified as a method for zinc and zinc-coated samples. Afterwards, this paper introduces the corrosion product layer resistance RL as a promising parameter to evaluate the protective power of zinc coatings. Results are verified with EIS and FTIR measurements. An example on a representative zinc coating demonstrates the practical application. PB - Elsevier Ltd. KW - Gel electrolytes KW - Agar KW - Zinc coatings KW - Atmospheric exposure KW - Corrosion PY - 2021 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/52605 AN - OPUS4-52605 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526053 SN - 0013-4686 VL - 385 SP - 138191 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany