PVD coating

In a simple cosine-flux model, a 4.00 µm normal-incidence deposit becomes 2.83 µm at 45° and 2.00 µm at 60° from the normal. Real source angles, plasma effects and part rotation affect local coverage. Verify thickness at critical surfaces and qualify substrate temperature separately.

What the process name establishes

PVD specifies a physical vapor source. Identify the coating composition, stack, substrate and functional requirements for the actual part.

Ionbond describes sputtering, which bombards a target with energetic gas ions, and cathodic arc, which evaporates target material through vacuum-arc discharges. Reactive gases can participate in forming the final coating. Their presence does not automatically make the process CVD: the source and deposition mechanism matter. Ionbond PVD technology

A trade name, color or coating acronym does not supply all acceptance requirements. Identify substrate preparation, layer stack, local thickness, significant surfaces and functional tests. Keep the coating's properties distinct from the coated component's load capacity and permissible service environment.

Temperature and substrate compatibility

Ionbond's named service describes typical PVD processing at 250–450°C, while identifying special cases below 70°C or up to 600°C. Its range depends on substrate and application. Therefore “PVD is cold” is not a sufficient compatibility review for a finished heat-treated component. Ionbond process ranges

A contrasting example is Oerlikon Balzers' plastic metallization route, described at a maximum 80°C with multi-axis part rotation. Its listed plastic and prepared-substrate applications are a separate system, not evidence that the same route provides the properties of an engineering tool coating. Oerlikon plastic metallization

Provide alloy/material, heat treatment, required final hardness, existing coatings and assembled materials before processing. Review the actual thermal cycle and preparation against those conditions. Do not evaluate suitability only by comparing deposition temperature with melting point; retain finished dimensional and material-property requirements.

Preparation, contacts and coverage

Cleanliness and substrate condition are part of the coating system. Oerlikon's coated-components guide describes checking material and surface condition, establishing preparation with the customer, cleaning, fixturing and final inspection. Its example sequence includes heating and ion treatment before deposition. Those are named process stages, not a transferable recipe for every PVD machine or substrate. Oerlikon component-processing guide, printed pages 72–73

Identify incoming roughness, defects, machining fluids and prior treatments. A thin deposit should not silently be expected to hide an unacceptable substrate defect. Agree any pre-polishing or other preparation and preserve enough dimensional allowance for the complete route.

Ionbond explicitly describes directional, line-of-sight deposition and part rotation to obtain its required coverage. Internal regions and contact/shadow areas therefore need review. Do not turn an external coupon thickness into proof that a deep passage received the same layer. Ionbond geometry discussion

Provide drawings of recesses, holes, coating boundaries and functional surfaces. Agree masking, fixture contacts and inspection locations before production. Define what must be coated, what must remain uncoated and how representative evidence will be obtained for inaccessible areas.

Original directional-flux illustration

Consider an ideal collimated beam depositing material on a stationary flat patch. Assume constant density and sticking probability, no scattering, no re-emission and no rotation. Let θ be the angle between the incident beam and the patch's surface normal. The patch presents projected area A × cos θ, giving the idealized relationship:

local thickness = normal-incidence thickness × cos θ.

If the normal-incidence thickness would be 4.00 µm, the same assumed exposure at 45° gives:

4.00 × cos 45° = 2.83 µm.

At 60°, it gives 2.00 µm. These are geometric flux examples, not predictions for a commercial reactor. Real source angular distributions, plasma effects, multiple sources, rotation and resputtering can change the result. The model explains why orientation matters; it does not provide a coating factor for a bore, an acceptance limit or a production setting.

A separate dimensional check is still needed. Under an assumed uniform additive 3 µm coating, a shaft gains 6 µm on diameter. Actual local thickness and any preparation or thermal dimensional change must be evaluated separately. Neither illustrative calculation establishes complete-part conformity.

Thickness and adhesion tests have scopes

Specify the method and locations for the actual coating/substrate system. ISO 26423:2009, edition 1, January 2009, confirmed in 2025, describes ceramic-coating thickness by crater grinding and microscopy. Its public scope excludes use where coating/substrate roughness exceeds 20% of coating thickness because of measurement uncertainty. It is not a universal thickness procedure for every film marketed as PVD. ISO 26423 scope

ISO 20502:2005, edition 1, August 2005, confirmed in 2019 and marked for revision, describes ceramic-coating scratch tests using a diamond stylus under constant or increasing normal force. Adhesive and/or cohesive failure can occur. Interpret the reported result with the method, substrate, coating and failure criterion; a scratch critical load is not automatically a universal bond strength or service-life prediction. ISO 20502 scope

Oerlikon's guide separately identifies coating thickness, hardness, adhesion and visual inspection in its processing example. Select acceptance tests for the required function rather than assuming one result establishes all properties. A hardness measurement does not establish the absence of pores or the allowable temperature of the assembled component. Oerlikon final inspection

Production handoff

Retain the part/revision, substrate and condition, coating identity and layer structure, approved deposition/preparation route, thermal restrictions, significant surfaces, masking/contact map, thickness locations, final dimensions and functional acceptance criteria. Specify handling and any later forming, grinding or assembly that can change the coating.

Use representative parts and test specimens, with a defined relationship to the accepted production lot. Resolve changes to substrate condition, coating stack, preparation or fixture/loading arrangement against the actual qualification requirements. These are proposed handoff fields rather than a normative coating specification.

Source versions

The cited supplier technology pages have no verified technical revision date here. The Oerlikon component guide identifies itself on printed page 4 as the third edition, November 2010; its historical examples do not define universal current PVD capability. ISO edition/confirmation dates above are distinguished from a new technical publication. The flux and dimensional arithmetic and proposed handoff guidance are original explanations.

Surface-finishing processes