BS EN ISO 9717:2017

What is this standard about?

It specifies requirements for how ferrous metals, aluminium, zinc, cadmium and their alloys should be processed to produce coatings that essentially consist of inorganic phosphates. These coatings will be used in conjunction with supplementary finishes to protect the basis metal against corrosion and to provide anti-wear properties to sliding surfaces; adhesion to organic finishes; and ease of cold forming operation.

Who is this standard for?

It’s relevant to anyone using phosphates as a substrate for coating with paints, typically in military and construction applications. The standard is also the basis of many OEM standards used in the automotive industry. 

Why should you use this standard?

It supplies coating weights and types of phosphates for given applications. 

It also provides the requirements for inorganic phosphate use in coatings to prevent corrosion, improve adhesion, modify surface friction and facilitate cold forming.

What’s changed since the last update?

The original standard included only one process although other processes are possible. This revision has removed the specified process. Also Clauses 4 and 5 have been revised, some annexes have been updated and a new annexe added on corrosion resistance. Specifically:

• The scope has been clarified 
• The normative references have been updated
• The terms and definitions have been replaced by a reference to ISO 2080 
• Clause 4 has been revised
• The terms in Clause 5 have been revised
• Requirements for the phosphate layer have been revised
• Statements on corrosion resistance have been shifted to a new Annex A
• Annex B on salt spray testing has been revised
• Annex C to the properties of the phosphate layers has been revised