scope:

This Defence Standard (Def Stan) 02-828 defines the requirements for thermal spray deposition of coatings using automatic or semi-automatic methods onto engineering components. Manual Spraying, i.e. hand held spray gun is prohibited. The coatings shall be metallic, ceramic or cermet (see Annex A) and their purposes may be for the following:

Corrosion, heat, or oxidation resistance;

Wear resistance;

Dimensional reclamation;

Electrical conductivity or resistivity;

RF shielding;

Machine seal clearances.

The physical characteristics of thermally sprayed coatings and the preparation of the component for spraying, together with spraying methods and procedures, are covered. The requirements that are necessary to achieve repeatable quality are defined.

Where appropriate throughout this Standard reference is made to European/International Standards that supersede any National Standard on the same topic.

This Standard does not cover the thermal spraying of structural steelwork for the purpose of corrosion resistance. See BS EN 22063.

This Standard does not cover coatings produced by Weld Overlay Cladding or the Plasma Transferred Arc process, which are classified as welding processes. See Def Stan 02-875 and Def Stan 03-16. The Plasma Transferred Arc process is akin to TIG welding in that the arc is struck by a tungsten electrode, which melts the substrate surface fully fusing the coating to the substrate. Therefore, the limitations at Clause 5.7 will not apply.

The Argon Shrouded Plasma and Vacuum Plasma spraying techniques, which utilize inert gas atmospheres, at atmospheric and low pressure respectively, to deposit dense, essentially oxidefree coatings onto metallic substrates, require specialized technical support and are therefore beyond the scope of this standard.

This standard is a Category 2 standard as described in foreword paragraph15b.