{"id":30469,"date":"2026-10-19T13:48:56","date_gmt":"2026-10-19T05:48:56","guid":{"rendered":""},"modified":"2026-10-19T13:48:56","modified_gmt":"2026-10-19T05:48:56","slug":"fastener-surface-treatments-explained","status":"publish","type":"post","link":"https:\/\/www.daosanfasteners.com\/ar\/fastener-surface-treatments-explained\/","title":{"rendered":"Fastener Surface Treatments Explained"},"content":{"rendered":"

Plain and Black Oxide<\/h2>\n

Plain fasteners are untreated and are only suitable for dry indoor use or for parts that will be painted after assembly.<\/p>\n

Black oxide produces a thin dark film that holds oil well. It is common on socket head screws and machine tools where dimensional accuracy matters more than corrosion resistance.<\/p>\n

Zinc Plating and Passivation<\/h2>\n

Electroplated zinc with a clear or yellow passivation is the most common finish for indoor hardware and general machinery.<\/p>\n

A yellow or blue passivation slows the formation of white corrosion products. A black passivation gives the same protection with a dark appearance.<\/p>\n

Hot-Dip Galvanizing<\/h2>\n

Hot-dip galvanizing is the standard for outdoor structural work, giving a thick, hard coating with a long service life.<\/p>\n

Because the coating thickens the thread, galvanized nuts are tapped oversize and must be supplied with their matching bolts.<\/p>\n

Specialist Coatings<\/h2>\n

Dacromet is a zinc-aluminium flake coating applied in a dip-spin process. It avoids hydrogen embrittlement, so it suits high grade bolts such as 10.9 and 12.9.<\/p>\n

PTFE and Xylan coatings reduce friction and resist chemicals, useful for valves, pumps and food equipment.<\/p>\n

For the most aggressive environments, stainless steel or a duplex fastener removes the need for a coating altogether.<\/p>\n

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Need Help Choosing the Right Fastener?<\/h2>\n

Tell us the standard, size, grade and finish you need and our team will come back with a price and lead time, usually within 24 hours.<\/p>\n<\/div>\n

\u0625\u0631\u0633\u0627\u0644 \u0631\u0633\u0627\u0644\u0629<\/a>or request a sample →<\/a><\/div>\n<\/div>\n
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Recommend Products<\/h2>\n
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\"Hexagon<\/span>Hexagon Bolts<\/span><\/a>\"High<\/span>High Strength Bolts<\/span><\/a>\"Hexagon<\/span>Hexagon Nuts<\/span><\/a>\"Threaded<\/span>Threaded Rods<\/span><\/a>\"Allen<\/span>Allen Bolts<\/span><\/a>\"U-Bolt\"<\/span>U-Bolt<\/span><\/a>\"Locking<\/span>Locking Nut with Nylon<\/span><\/a>\"Double<\/span>Double End Studs<\/span><\/a>\"Hexagon<\/span>Hexagon Bolts<\/span><\/a>\"High<\/span>High Strength Bolts<\/span><\/a>\"Hexagon<\/span>Hexagon Nuts<\/span><\/a>\"Threaded<\/span>Threaded Rods<\/span><\/a>\"Allen<\/span>Allen Bolts<\/span><\/a>\"U-Bolt\"<\/span>U-Bolt<\/span><\/a>\"Locking<\/span>Locking Nut with Nylon<\/span><\/a>\"Double<\/span>Double End Studs<\/span><\/a><\/div>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"

From plain steel through to specialist coatings, the surface treatment decides how a fastener performs in service and how long it lasts. Here is what each option is for.<\/p>","protected":false},"author":1,"featured_media":30446,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[65],"tags":[],"class_list":["post-30469","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technical"],"_links":{"self":[{"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/posts\/30469","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/comments?post=30469"}],"version-history":[{"count":0,"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/posts\/30469\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/media\/30446"}],"wp:attachment":[{"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/media?parent=30469"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/categories?post=30469"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.daosanfasteners.com\/ar\/wp-json\/wp\/v2\/tags?post=30469"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}