TS EN 657

TS EN 657 is a terminology and classification standard for thermal spraying. Standards of this kind help ensure that the same words are used consistently across workshops, laboratories, specifications, and supply chains, which improves communication in surface engineering and coating practice. Although this edition is withdrawn, the subject remains technically important because thermal spraying depends on a precise shared vocabulary.

What thermal-spraying terminology refers to

Thermal spraying is a family of surface-coating processes in which a coating material is heated and accelerated toward a substrate, then solidifies to form a layer. In general technical context, the family can include wire-, powder-, or rod-fed processes and may use different energy sources such as flame, arc, or plasma systems. The value of a terminology standard is that it separates closely related concepts that are easy to confuse in practice, such as coating, substrate, spray material, bond coat, and surface preparation.

Why classification matters in practice

Thermal-spraying processes are not distinguished only by equipment; they are also commonly grouped by feedstock form, energy source, particle formation, and the intended function of the coating. Classification helps engineers compare similar processes, write clearer specifications, and choose the most suitable process family for a task. In general technical use, that supports applications such as wear resistance, corrosion protection, thermal barriers, or dimensional restoration. The title of TS EN 657 indicates that the document is primarily about a shared technical framework and vocabulary rather than performance limits or product testing requirements.