{"id":3998,"date":"2025-09-24T07:46:45","date_gmt":"2025-09-24T05:46:45","guid":{"rendered":"https:\/\/www.appcz.eu\/?p=3998"},"modified":"2025-12-18T22:46:15","modified_gmt":"2025-12-18T21:46:15","slug":"salt-spray-corrosion-test-a-fast-quality-check-for-e-coat-but-not-without-its-limits","status":"publish","type":"post","link":"https:\/\/www.appcz.eu\/en\/salt-spray-corrosion-test-a-fast-quality-check-for-e-coat-but-not-without-its-limits\/","title":{"rendered":"Salt spray corrosion test: a fast quality check for e-coat, but not without its limits"},"content":{"rendered":"<p><strong>Cathodic dip coating (E-coat) forms the foundation of corrosion protection in the automotive industry. It ensures the long-term durability of vehicle bodies and individual components, which is why its quality is continuously verified through corrosion testing. One of the most commonly used methods is the salt spray test, which quickly reveals weak points in the coating. At Automotive Painting Partners, we perform this test in-house, giving customers confidence that their parts can withstand even demanding operating conditions.<\/strong><\/p>\n<h2><span style=\"font-weight: 400;\">The \u010cSN EN ISO 9227 standard and its three variants\u00a0<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">The salt spray test is standardised according to \u010cSN EN ISO 9227, which defines three basic types of tests differing in environmental aggressiveness:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>NSS (Neutral Salt Spray)<\/b><span style=\"font-weight: 400;\"> \u2013 the most widely used test with a neutral NaCl solution (5%, pH 6.5\u20137.2). Suitable for evaluating intact coatings and detecting defects such as pores or uneven thickness.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>AASS (Acetic Acid Salt Spray)<\/b><span style=\"font-weight: 400;\"> \u2013 the NaCl solution is acidified with acetic acid (pH 3.1\u20133.3). This more aggressive environment enables faster evaluation of coatings sensitive to acidic conditions and is often used for thin organic layers.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>CASS (Copper-Accelerated Acetic Acid Salt Spray)<\/b><span style=\"font-weight: 400;\"> \u2013 the most demanding variant, enhanced with copper(II) sulphate. It is used mainly for decorative nickel\u2013chrome coatings.<\/span><\/li>\n<\/ul>\n<h2><span style=\"font-weight: 400;\">Testing at APP: two corrosion chambers and one condensation chamber<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">At <\/span><a href=\"https:\/\/www.appcz.eu\/en\/\"><span style=\"font-weight: 400;\">Automotive Painting Partners<\/span><\/a><span style=\"font-weight: 400;\">, we operate two corrosion chambers and one condensation chamber. This allows us to perform <\/span><b>NSS<\/b><span style=\"font-weight: 400;\"> and condensation tests independently on site. <\/span><b>AASS<\/b><span style=\"font-weight: 400;\"> and <\/span><b>CASS<\/b><span style=\"font-weight: 400;\"> tests are carried out in cooperation with trusted external laboratories. Thanks to this combination, we can guarantee our customers that their parts achieve <\/span><b>consistently <\/b><a href=\"https:\/\/www.appcz.eu\/en\/cathodic-dip-coating-ktl\/\"><span style=\"font-weight: 400;\">excellent corrosion resistance<\/span><\/a><span style=\"font-weight: 400;\">.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-3652 size-large\" src=\"https:\/\/www.appcz.eu\/wp-content\/uploads\/2025\/09\/app-korozni-zkousky-2-1024x683.jpg\" alt=\"\" width=\"1024\" height=\"683\" srcset=\"https:\/\/www.appcz.eu\/wp-content\/uploads\/2025\/09\/app-korozni-zkousky-2-1024x683.jpg 1024w, https:\/\/www.appcz.eu\/wp-content\/uploads\/2025\/09\/app-korozni-zkousky-2-300x200.jpg 300w\" sizes=\"auto, (max-width:767px) 767px, (max-width:1024px) 100vw, 1024px\" \/><\/p>\n<h2><span style=\"font-weight: 400;\">Benefits of salt spray testing<\/span><\/h2>\n<p><b>The main advantages of these tests:<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">rapid identification of defects and weak points in the E-coat layer,<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">detection of issues in surface pretreatment or coating application,<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">standardised and repeatable conditions \u2013 enabling comparison of results across manufacturers and suppliers,<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">applicability in both early development stages and serial production for routine quality control.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">For engineers and technicians, the tests represent a <\/span><b>reliable tool for verifying coating quality<\/b><span style=\"font-weight: 400;\"> before components enter service.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">Limitations and proper interpretation of results<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">The salt spray test also has <\/span><b>limitations<\/b><span style=\"font-weight: 400;\">. In the chamber, the sample is exposed to <\/span><b>continuous salt aerosol<\/b><span style=\"font-weight: 400;\"> at a constant temperature. This scenario differs significantly from real-world conditions, where humidity and dryness alternate, temperatures fluctuate, and mechanical impacts (e.g. stone chipping) also occur.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Therefore, results cannot be directly translated into the real-life service life of a coating. For more comprehensive evaluation, cyclic corrosion tests are also used, as they simulate real conditions more accurately. Although these are more time and cost-intensive (400\u2013900 hours), they provide a much clearer picture. At APP, we provide these in cooperation with external laboratories, allowing us to offer customers <\/span><a href=\"https:\/\/www.appcz.eu\/en\/comprehensive-surface-treatments-in-practice-what-we-do-at-app-to-achieve-perfect-results\/\"><span style=\"font-weight: 400;\">comprehensive testing services.<\/span><\/a><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-3649 size-large\" src=\"https:\/\/www.appcz.eu\/wp-content\/uploads\/2025\/09\/app-korozni-zkousky-3-1024x682.jpg\" alt=\"\" width=\"1024\" height=\"682\" srcset=\"https:\/\/www.appcz.eu\/wp-content\/uploads\/2025\/09\/app-korozni-zkousky-3-1024x682.jpg 1024w, https:\/\/www.appcz.eu\/wp-content\/uploads\/2025\/09\/app-korozni-zkousky-3-300x200.jpg 300w\" sizes=\"auto, (max-width:767px) 767px, (max-width:1024px) 100vw, 1024px\" \/><\/p>\n<h2><span style=\"font-weight: 400;\">Why salt spray alone is not enough<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">The salt spray test according to \u010cSN EN ISO 9227 is a proven and fast way to detect defects in E-coat layers. However, it is only one tool in the broader assessment process \u2013 true reliability comes from <\/span><b>a comprehensive approach that incorporates multiple types of testing.\u00a0<\/b><\/p>\n<p><span style=\"font-weight: 400;\">The right combination of methods gives engineers and technicians confidence when assessing the durability of protective systems, not only in the automotive industry but also <\/span><a href=\"https:\/\/www.appcz.eu\/en\/cathodic-dip-coating-ktl\/\"><span style=\"font-weight: 400;\">across other sectors<\/span><\/a> <span style=\"font-weight: 400;\">\u2013 from mechanical engineering and agricultural or construction machinery to medical technology.<\/span><\/p>\n<p><b>Do you want assurance that your parts will perform even under the most demanding conditions? <\/b><a href=\"https:\/\/www.appcz.eu\/en\/contact\/\"><b>Contact us<\/b><\/a><b> \u2013 we will provide comprehensive testing and guarantee top-level corrosion resistance.<\/b><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Cathodic dip coating (E-coat) forms the foundation of corrosion protection in the automotive industry. It ensures the long-term durability of vehicle bodies and individual components, which<span class=\"excerpt-hellip\"> [\u2026]<\/span><\/p>\n","protected":false},"author":8,"featured_media":3645,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21],"tags":[],"class_list":["post-3998","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/posts\/3998","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/comments?post=3998"}],"version-history":[{"count":2,"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/posts\/3998\/revisions"}],"predecessor-version":[{"id":4000,"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/posts\/3998\/revisions\/4000"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/media\/3645"}],"wp:attachment":[{"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/media?parent=3998"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/categories?post=3998"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.appcz.eu\/en\/wp-json\/wp\/v2\/tags?post=3998"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}