Annual German ZinKlad Meeting 2013

ZinKlad logo

25th April 2013 was the date for the annual meeting of the German ZinKlad “club“. This annual gathering facilitates open discussion between all the German ZinKlad Approved Platers and the MacDermid sales, technical and OEM teams.

German ZinKlad Applicators

German ZinKlad Applicators

This year, there was a special surprise as MacDermid Sales Director, Michael Barz, handed out engraved metallic ZAP certificates to mark more than 10 years success of the ZinKlad program in Germany!

The meeting started by Managing Director, Thomas Dyllus, explaining the structure and sales growth of MacDermid GmbH. He also outlined the strategy of innovation and collaboration with the major global automotive manufactures. Both key points which benefit the platers themselves by generating new business potential and technologies which can fulfill these opportunities.

The discussion then turned to the global perspective. European Marketing Manager Mr. Mark Baker highlighted some key successes from the past year in the ZinKlad program which included:

• The rise to some 70 ZAP worldwide including 30 in Europe
• Approval by GM for ZinKlad 1000
• John Deere entering the approval process for ZinKlad 250
• New ZAPs in the emerging India and Thailand markets
• Ford approval of ZinKlad 1000 (S450) and changes to the S437 program which exclusively calls out ZinKlad 96 and 250

Finally this discussion was finished by outlining the ZinKlad vision for the next decade, continued global availability, compliance and performance improvement.

OEM Key Account Managers Otfried Bertram (VW) and Rainer Lakner (BMW/Daimler) then took the opportunity to update the delegates with the latest data from the German automotive industry. This included production, sales and longer term strategies.
They also dedicated time to the success of the MacDermid zinc-nickel Enviralloy NiFlex 12 coated fluid transfer tubes which are post plate deformed. Along with the synergistic TriPass ELV 3100 and HydroKlad Si, this coating is fully approved to VW TL244. As the coating is able to meet the performance specification after post plate deformation, this represents a major cost saving for the automotive
tube supply chain.

The agenda then turned to what tomorrow holds in store for the platers of sacrificial coatings. Christian Zimmermann, Global Anti-corrosion Junior Product Manager introduced the REACH legislation, and in particular how it relates to cobalt containing trivalent passivates. As this (cobalt) material may be prohibited in future, MacDermid already have cobalt free passivation systems working in the field. The new 7000 range of TriPass trivalent chromium passivates can be applied to both zinc and zinc alloys and operate in both rack and barrel.

A new zinc-nickel was then introduced, Enviralloy Ni-Speed. A bright zinc-nickel for rack plating which is designed to overcome deficiencies with current processes, namely brightness and plating speed. By adopting this new process platers can give a better appearance to their zinc-nickel plated parts and produce them in a shorter plating time, thus increasing production capacity.

ZinKlad certificate

ZinKlad metal certificate

The meeting concluded with an open discussion by the Platers before being presented with the new engraved plaques. Everyone agreed that the meeting had added value to their current perspective of the German automotive requirements. They all look forward to the next meeting in 2014, and of course hanging the new plaques on their reception walls!For further information, please contact Michael Barz –


MacDermid Platers Calculator – Now available on Smartphones

Obtain quick calculations of average processing data for electroplating.

The Platers Calculator is able to estimate electroplating data for most common plated metals, including copper, nickel, chromium and zinc. Output results include average plating times, thicknesses and weight of metal deposited. There is also a guide to calculating the current densities for the Hull Cell Test procedure.

Available for Android, Blackberry, Iphones and Ipads, technicians will find the App quicker than using reference books and easier than their desktop software to provide guide calculations in real time. The Platers Calculator can be downloaded from the Macdermid.industrial web site.

This application is designed to calculate plating times, thicknesses, weight of metal consumed and cathode efficiency. Please note that the results displayed will give the average plating thickness deposited. If minimum thickness specifications are required, then an extra allowance will be required depending on the cell geometry and throwing power of the plating electrolyte.

To use the application:

  1. Select the metal being plated from the drop down box. The program will then display the atomic weight, density and valency of the metal being deposited. It will also display a default cathodic efficiency which is typical of the plating electrolyte selected. However, this parameter can be changed by typing in a different value.
  2. Choose one of the options: Thickness, time, weight or efficiency.
  • Choosing “thickness” will prompt for values of current density and time and will calculate the average plating thickness.
  • Choosing “time” will prompt for values of current density and required average thickness and will calculate the required plating time.
  • Choosing “weight” will prompt for current density and time and will calculate the weight of deposit and choosing “efficiency” will prompt for current, time and weight of deposit and will calculate the cathodic efficiency.

In addition to plating calculations, the program will also calculate Hull Cell parameters. This feature can be accessed by selecting the Hull Cell tab. The use of this application is self explanatory. The cell current is selected with the top slider and the distance along the Hull Cell panel from the high current density end is set with the second slider. The primary current density at this point is then displayed.

Selecting the conversions tab allows you to select many different units (for example grammes per litre to ounces per US gallon). Simply select the conversion required from the drop down box, enter the amount to be converted and press calculate to get the result.

Ford – Change to the WSS-M21P17 specific

Ford – Change to the WSS-M21P17 specification
Ford has authorized MacDermid to communicate changes to the S437 (ZinKlad 250) range of zinc electroplated fastener finishes. The current WSS-M21P17 will move to the new specification WSS-M21P52. The major changes involve cyclical corrosion testing and a change to some of their torque-tension requirements.

Read more…

Coatings for high tensile fasteners

Mechanical plating

High tensile fasteners are mechanically plated

When coating performance is considered, hours to white or red rust are the normal criteria. However with high tensile fasteners, threaded or unthreaded, being free of hydrogen embrittlement is an equally important factor. For this reason components such as rivets and safety critical fasteners are zinc coated using a mechanically applied process rather than traditional electroplate. This process also offers advantages in bulk application against organic dip spin that even the smallest fastener can be treated without head / recess fill or parts sticking together.

Mechanical plating

 In the mechanical plating process the zinc is present as fine dust. It is deposited by a cold welding process. Impact energy is transferred from a rotating open ended barrel through glass beads to the zinc dust. This impacts the zinc against the steel substrate. The resulting deposit provides corrosion protection to the articles without introducing hydrogen embrittlement into the part.

The main features of the mechanical zinc process can be summarised as:

• No risk of Hydrogen Embrittlement
• Excellent corrosion protection
• Choice of zinc, zinc aluminium or zinc tin alloys
• Automated bulk process
• Room temperature, cold welding batch by batch capability
• Non-electrolytic process
• Thicknesses can range from 8µm to over 75µm

The benefits to the specifier are reliability, security and value.


 The consistency of mechanical plating can be demonstrated by the replication in processing and the resultant coating. Additionally mechanical plating is specified by automotive manufacturers within the ZinKlad approved applicator program.

Plating process

The plating process is defined by process steps which are always the same. The only change, batch to batch, is the amount of material added (i.e. zinc dust). These quantities are correlated to the surface area being coated and the thickness required. These factors mean that the results are reproducible time and time again.

Coating performance

250 hours neutral salt spray

Protects for more than 250 hours in neutral salt spray

This reproducibility means a predictable coating is produced. Mechanical zinc plating, specified for over 30 years now by many major automotive manufacturers, delivers corrosion resistance similar to electroplated zinc for the same given zinc thickness. This means that an 8µm coating will resist more than 250 hours to red rust. Therefore exceeding requirements for:

• Non threaded fasteners such as rivets for joining metal
• Threaded fasteners used in safety critical assemblies such as seat belt mountings

Applicator program

Automotive companies often specify their surface finishing within an applicator program. This program aids coating reliability through a common audited standard. This helps to ensure the same coating performance throughout the applicator base, regardless of geographical applicator location.


A common feature of the 2 component types mentioned above is that both are constructed from high tensile steel. It is generally accepted that steels having a hardness above Rockwell C-40 are susceptible to hydrogen embrittlement.

One of the issues of hydrogen embrittlement, is that the higher-strength steels which are used to bear high loads are the very steels which can fail from hydrogen embrittlement at loads much less than their design load. The role which the hydrogen plays in the failure mechanism includes factors such as internal pressure from gas formation, formation of metal hydrides, stress concentration due to interactions with metal imperfections, and micropore or microcrack formation.

This now returns to the need for a coating free of hydrogen embrittlement to prevent failure in use. For the components mentioned above, hydrogen embrittlement could mean:

• A Rivet which fails to pierce and join metal layers
• A safety critical bolt which fails under intense load


Rivets in pile

High tensile self piercing rivets are also plated with mechical zinc alloys

Mechanical plating is an economical method of producing zinc coatings on high tensile steels due to:• No need for the hydrogen de-embrittlement process – Electroplated zinc coatings need to be de-embrittled within 2 hours of plating at 200ºC for 4 – 24 hours (dependant on part geometry and packing density). Additionally any passivation must be applied following this baking operation. These steps add cost due to increased process stages and energy consumption.

 • Automated equipment for bulk processing – Mechanical plating is applied in bulk processing, often in automated equipment. This increases productivity due to high loading and reduces operator costs.

• Coating uniformity and freedom from parts ‘sticking’ – These factors can reduce costs when compared to organic dip spin finishes, especially on rivets or fasteners with recessed heads.

• Low environmental impact – Finally the mechanical process results in very little waste material. This is because the majority of the material added during the plating operation is consumed to produce the final deposit.


Mechanical plating, extensively specified for over 30 years now, is considered one of the 3 primary coating systems for threaded and non-threaded fasteners. Primarily specified to provide sacrificial protection to high tensile steel components, it offers advantages in its ability to treat small and recessed parts without sticking or filling issues. The coating is uniform and consistent and can be specified for both joining and safety critical applications. Finally the bulk nature and low waste make mechanically plated sacrificial coatings extremely cost effective.

ZinKlad moves into India

  ZinKlad Plated Bolts

LPS  and Sundram become ZinKlad Approved Applicators

MacDermid India are very pleased to add LPS (Rohtak) and Sundram Fasteners (Krishnapuram) to our list of ZinKlad Approved Applicators (ZAPs). The approval of these new ZAPs reflects the growing importance of surface finishing to global automotive standards in india market.

India fastener market      India flag

The majority of fasteners in India today are consumed by the developing automotive sector. With global OEM’s such as Ford, Honda and Hyundai  now manufacturing vehicles for both domestic and export sales, the use of hexavalent chromium free passivates is becoming an important factor in this supply chain.


Lakshmi Precision Screws Ltd, established in 1972, provides high tensile fastening technology globally. having Joint Ventures, License Agreements, and Alliances with different fastening companies worldwide.  The Company is located in Rohtak (Haryana) just sixty kilometers from New Delhi.

Bolts plated in ZinKlad 1000

LPS offer ZinKlad 250 and ZinKlad 1000

Recently LPS has established two operating units, one in Rohtak and another in Industrial Modal Town, Manesar. Collectively all the four units have a total production capacity of 25,000 metric tons (MT) per annum.

LPS also caters to the needs of  wind energy, oil & gas, locomotives, agriculture equipment and machine building industries.

Sundram Fasteners

ZinKlad 250 plating

Sundram offer ZinKlad 250 finish

Part of the US based TVS Group and headquartered in Chennai, Sundram Fasteners has become a supplier of choice to leading customers in the automotive and industrial segments worldwide.

Over the years, the Company has acquired cutting-edge technological competencies in forging, metal forming, close-tolerance machining, heat treatment, surface finishing and assembly. Manufacturing locations are supported by engineering and design personnel working on new product design and development.

The product range consists of high-tensile fasteners, powder metal components, cold extruded parts, hot forged components, radiator caps, automotive pumps, gear shifters, gears and couplings, hubs and shafts, tappets and iron powder.

ZinKladZinKlad logo

Launched 10 years ago to help automotive engineers specify the right products to meet End of Life Vehicle requirements it has enabled many global OEM’s to specify higher standards than they had previously achieved.

Today ZinKlad represents not only the best method for achieving hexavalent chromium free performance coatings, but also:

  • Approved applicators: Applying these products to a common audited standard ensures the same coating performance throughout the applicator base.
  • High performance: Exceeding corrosion resistance of hexavalent chromate systems and exceptionally consistent torque and tension characteristics.
  • Global consistency: Wherever ZinKlad coatings are applied, applicators know they are using the same high performance products.

Of course, compliance with legislation, such as ELV & RoHS, and predictable torque-tension performance continue to be essential requirements. ZinKlad continues to deliver on all of these needs.

ZinKlad Welcomes…Retsacoat – Portugal

Congratulations to the Retsacoat team seen receiving there new ZinKlad certificate from Daniel Algar and Belina Raposo MacDermid Portugal.

RETSACOATTratamentos de Superficies Metálicas Lda, leading company in thermal and anti-corrosive treatments, started its activity in 2001. Retsacoat is a member of the Pecol business group. This partnership has been essential for the development of our current surface treatments.

To View this article on Retsacoat and ZinKlad in Spanish / online ebook, follow link  

Retsacoat started as lamellar (dip spin) zinc applicators inPortugal. In 2006, as a result of the Cr VI restriction in surface treatments, we became approved for the application of chromium-free lamellar zinc processes.

These thin film anti-corrosive treatments are the best alternative for a great number of parts. For example, the absence of chemical pickling eliminates the risk of hydrogen embrittlement. The thin thickness and integrated lubrication, allows a perfect assembly, even with small metric screws. Lubrication, an increasingly important issue, allows us to meet these market demands.

Recently we completed our portfolio of electrolytic treatments with the implementation of a fully automatic line for zinc, zinc nickel and zinc iron.

The support and collaboration of MacDermid has been fundamental. From the beginning of 2012, we are the first company in Portugal certified with the process ZinKlad 250 and ZinKlad 1000. With these new processes, we offer our customers the best solution in electrolytic finishing processes.

For lubrication of the ZinKlad finishes we offer both Torque ‘n’ Tension 11, and Torque ‘n’ Tension 15. Collectively these provide the optimal controlling the coefficient of friction characteristics.


Retsacoat have always been a pioneer in the latest equipment and finishing technology. We have implemented fully automatic lines that allow us to deliver finishes of high quality and consistency, at very competitive prices and with a reduced time for deliveries.


Quality is always a high priority for us. All surface and thermal treatments require a perfect control, both of the processes and finished product. In our in-house laboratories we carry out the most demanding tests including hardness testing, deposit observations by microscope, neutral spray salt, measurements of thickness by X-ray and also coefficients of friction.


Our concern for the environment has always been an essential part of the process development. Effluent gases such as liquid heat and finishing treatments are controlled by our in-house treatment equipment.

RETSACOAT – the solution for your mechanical parts.

Improving your friction control coatings

The extensive use of topcoats for fasteners began in the 1980’s. The primary need was to enhance corrosion protection and were generically known as leach and seal, due to their ability to turn yellow passivates to an almost silver colour. An improvement to leach and seal was to incorporate dry film lubricants in the coating to lower the coefficient of friction (CoF) of a fastener. With the introduction of high performance trivalent chromium passivates in 2000, the technology evolved into processes applied at room temperature. These were more sympathetic to the underlying passivates, giving high quality black finishes. One major global automotive OEM followed this evolution, moving from hexavalent passivates with leach and seal, to trivalent passivates with a thin film topcoat and lubricant combination.

Leach and Seal

Arguably the best known leach and seal process is the MacDermid JS500 system. Used alone, it reduces the CoF range of pure zinc from >0.4 to 0.22 +/- 0.08. Combined with an integral lubricant it reduces the CoF to 0.12 (+/- 0.02). This integrated process (known as JS600) provided the required protection, improvement and lubrication for the majority of their fasteners.

Change instigates higher performance requirements

Around the year 2000, the ELV directive drove many automotive companies to upgrade their existing plated fastener finishes requirements. Typically this was the new specification:

  • Higher corrosion resistance
  • Compatibility with trivalent passivation
  • CoF 0.15 with a deviation of +/- 0.02
  • New CoF requirements for different fastener innovation
  • Identification with an integral UV tracer

The answer was a new breed of topcoats. These mixed inorganic and organic compounds gave thin topcoats which adhered to and respected the underlying passivate, gave significant improvements in neutral salt spray (corrosion) resistance and a very predictable CoF of the desired 0.15. As the topcoat is so thin and transparent, its application can be verified by the presence of tracers, which maybe seen under a UV lamp. Let us review how these new topcoats achieve these performance enhancements.

Higher corrosion resistance

Three effects are taking place to increase the overall protection: (i) water resistance (ii) corrosion inhibition (iii) adhesion to the passivate layer. The first line of defence is that the coating performs as a barrier layer. The topcoat prevents water reaching the surface by providing a strong hydrophobic layer. The homogeneity of the coating also prevents premature swelling of the coating by water absorption. The second defence is the presence of corrosion inhibitors throughout the coating. These help to seal the coating in any areas where minute discontinuities in the film might occur. Thirdly the adhesion to the passivate layer is so strong that any ‘undercutting’ of the film is prevented. This is particularly important on sharp profiles (where the coating will typically be thinner).

Compatibility with trivalent chromium passivates

The original leach and seal coatings were designed around hexavalent chromium passivates. The leach process ensured exceptional adhesion by combining the passivate with topcoat layer. Trivalent passivates are homogenous layers and not so easy to leach. So the new products had to adhere to a smooth and pore / crack free coating. They also had to be compatible with various types including thin film (typically blue) and thick film (iridescent or black) passivates.

Narrow range coefficient of friction

All fasteners have a designed maximum proof load. Creating the correct torque-tension relationship achieves maximum joint security without exceeding the proof load of the fastener. Zinc and zinc alloys have a relatively high and variable coefficient of friction. This can adversely affect the torque-tension properties of fasteners. Additionally passivates offer different levels of CoF. For example, it was noted that hexavalent passivates have an average CoF of 0.4, whereas a high build trivalent could be as high as 0.5.

If fasteners are used without a friction control fluid, the increase in friction results in lower bolt tension for a given torque, resulting in a joint weakness, which leads to poor clamping, insecure joints and, possibly premature bolt fatigue failure. Conversely too much can lead to bolt fracture and thread stripping. This factor becomes even more crucial in safety critical applications, such as wheels, seat belts, steering and suspension component system.

Torque n Tension for zinc nickel coatings

Torque n Tension for zinc nickel coatings

Therefore lubricated topcoats provide both a lower friction coating than simply metal to metal joints; and also makes the relationship more predictable, avoiding too low or too high clamping forces. Returning to our OEM, they changed to the newer topcoats in order to consistently achieve this predictable surface CoF. Another consideration was to ensure that all applicators, across an increasingly global supply chain, conformed to the same standard. Incorporation of the UV tracer permits verification that the right topcoat has been applied.

New range coefficient of friction requirements

As new fastener technology is introduced, new CoF ranges are demanded, whilst still maintaining the corrosion resistance and compatibility with trivalent passivates. The most current dry film lubricant systems can be tailored to meet these new CoF demands, while still returning low variability.


Dry film lubricants have evolved from leach and seal processes, designed primarily for hexavalent chromium passivates, to non leach systems compatible with trivalent chromium passivates. Coupled with outstanding corrosion resistance, the non-leach technology delivers exceptionally predictable torque-tension relationships without interfering with the dimensional tolerances. Additionally they can be modified to meet newer demands for friction ranges. This technology allowed a major global automotive OEM to improve the effectiveness of the fastener assembly operations by consistently returning desired corrosion and coefficient of friction on zinc and zinc alloy plate and trivalent passivation systems.

ZinKlad…Supporting the highest quality standards

The ZinKlad™ quality assurance programme is taking on the challenges for high performance automotive coatings of the future. Introduced 10 years ago, ZinKlad has enabled many global OEM’s to specify higher standards than they achieved with previous, hexavalent chromium based coatings.

Logo for ZinKlad

ZinKlad for high performance ELV compliant coating

In the new globalising world, OEM’s must change and adapt, and ZinKlad continues to respond to these requirements worldwide. Today ZinKlad offers high performance coatings, proven consistent quality and a global network of approved applicators.

Of course, compliance with legislation, such as ELV & RoHS, and predictable torque-tension performance continue to be essential requirements. ZinKlad continues to deliver on all of these needs.

So as we move into the future, you can be sure that the high corrosion resistant coatings, freedom from proscribed materials and consistent friction control, will remain today as true as when ZinKlad was first specified.


Zinc plated finishes for ZinKlad

ZinKlad Finishes

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