1. Metal Coatings

2. POWDER COATING

3. Why Powder Coat?
Elimination of VOCs - VOC is short for volatile organic compounds,
VOCs that escape into the air contribute to air pollution outdoors and inside our homes. ...
• Elimination of HAPs –Hazardous Air Pollutants.
• Reduction of ESOH Concerns ( Environmental Safety & Occupational Health)
• Reduction of Hazardous Waste

4. Why Powder Coat - continued
Single component, solvent free material
life limitations - good
• Process Efficiency
– Quick cure time
– Quick equipment prep and clean-up

5. Powder Coating
One of the most common methods of finishing metal surfaces.
Many items used everyday are powder coated.

6. Examples of Powder Coating
Everyday items such as mailboxes, chairs, appliances, automotive parts, tools, and construction materials.

7. The Process
A simple process, involving “spray painting” a fine plastic powder paint onto a metal surface.
Typically the surface is steel, aluminum or iron.
Most any surfaces can be coated, however, they must be able to withstand the high temperatures of the baking oven.

8. Before coating the part, the surface must be cleaned
Before coating the part, the surface must be cleaned. Often a sand blaster is used for this purpose. Parts must be totally free of contaminants that might effect the process such as grease, rust, oils, etc.
As the powder leaves the gun it is charged with static electricity. This charge then attracts the powder to the surface that is being coated.
After the parts are coated, they are then baked in an oven at about 400 degrees Fahrenheit for 10 to 45 minutes depending on the part. The actual part itself must reach these temperatures in order for curing to occur properly.
While in the oven, the powder melts and flows into a smooth finish. Curing time is critical, because under curing will cause loss of adhesion, and over curing will cause the strength characteristics of the powder to decrease.
Walk in oven

9. Unlike painting, there are no runs or drips with powder coating, and due to the static charge, there is no need for primers.
Additional clear coating and primers can be added to improve protection and depth.
If a mistake is made before baking, the powder can simply be blown off with an air nozzle and reapplied. If the mistake is realized after baking, the part must be sandblasted or the coating must be burned off.

10. Types of Powders
There are two main types of powders used for different applications.
Both types outperform most wet paint finishes and they both come in many varieties of colors, textures, and glosses.

11. Most indoor powders are made of epoxy
Most indoor powders are made of epoxy. Epoxy is the most durable powder, but it will chalk and dull from the sun’s ultraviolet rays.
Polyester powders are not as durable, but since they are unaffected by the sun, they should be used for most outdoor applications.

12. Equipment Used
Obviously the most important and expensive item to purchase is the oven.
The oven must be able to heat a part to around 400 degrees Fahrenheit for at least 10 minutes, sometimes more depending on the part.
The size of the oven depends on the sizes of parts the consumer wishes to coat. Obviously the larger the oven, the larger the part that can be coated.
With a larger oven, several parts can be baked at one time.

13. Ovens vary in style and price.
A small 6’x 8’x 10’ walk in gas oven is priced around $30,000.
A 100’ oven with a pass through conveyer can be as much as $100,000.
Small walk in oven

14. There are three main types of ovens; gas, electric, and infrared
There are three main types of ovens; gas, electric, and infrared. Infrared ovens work well if designed properly, however gas and electric tend to be more dependable. Electric ovens take longer to heat up, thus delaying the coating process. Obviously, the faster the oven heats, the faster the product will be coated.

15. Spray Guns Tribomatic spray gun. There are two types of spray guns,
Corona and a
Tribomatic spray gun.

16. Corona Gun Method Powder is applied using hand-held gun featuring a
high-voltage electrode at the front end.
Theelectrode creates ions, which impart a charge to the
powder particles exiting the gun, and the charged
particles are attracted to the electrically grounded target part.
Benefits
– Low film thickness possible ( mils)
Limitations
– Difficult to cover recessed areas and tight corners
due to Faraday Cage Effect

17. Tribomatic Gun Method
Powder is applied using hand-held gun designed to impart an electrostatic charge through friction between powder particles and gun internal material.
Benefits
– Even layer deposition
– Improved deposition into recesses
– Gun does not produce the Faraday Cage Effect
– Typically consumes 20% less powder than Corona Gun
Limitations
– Coats at half the speed of corona gun
– Electron donor/acceptor tendency between powder and
gun material must be great enough for adequate
charging of the powder

18. Other equipment needed:
the powder supplies
an air operated vacuum cleaner to retrieve any overspray
a spray booth.

19. Fluidized Bed Method Parts are pre-heated and suspended in an
airborne cloud of powder coating material.
• Benefits:
– Simplicity
– Less waste, lower
cost
• Limitations:
– Only coatings 10-
100 mil are possible
– Coating thickness
control is difficult

20. Electrostatic Fluidized Bed Method
Similar to standard fluidized bed system, but powder
is electrostatically charged and part is grounded so
that particles are attracted to part surface.
• Benefits
– Preheating of part not required
– 4-10 mil thickness of coating is possible
– Small parts coated uniformly, quickly
Limitations
– Inside corners tend to receive low film thickness due to Faraday Cage Effect
– Part size is limited by container size

21. Drawbacks to powder coating
The major drawback is the initial investment to begin the operation.
Powder coating does not have the strength or hardness characteristics that some other coating processes such as chrome or zinc have.
Chipping is another main problem with powder coating. This often results because the part was not baked long enough or kept at the proper cure temperature.

22. Benefits of Powder Coating
The biggest benefit of powder coating is that it is environmentally friendly.
There are no solvents as in paints, and thus no harmful air pollution. There is absolutely no hazardous waste created with this process.
Economic
Overspray can be air vacuumed and reused, thus reducing the amount of waste produced as well as saving cost.

23. Analysis
As can be seen for certain applications, powder coating is the most durable decorative finish available at this time.
A variety of different textures, colors, and glosses can be used.
The process is fairly simple and the cost is much less than other processes like chroming or zinc plating.
Also the initial investment is minimal compared to other processes.

24. Conclusion
With all the benefits of powder coating, it can be seen why it is such a widely applied technique. Obviously, if a person has the resources and demand for the procedure, they should think seriously about investing in the operation.

25. SUMMARY A powder coating material that will allow
us to overcome previous limitations of the
powder coating process resulting in:
• VOC, HAP and solvent free coating
• reduced labour hours
• lower costs

26. Tin plating
Tin plating is primarily for "functional" purposes such as providing a level of protection or corrosion resistance to a range of
Tin Plating is a lower cost alternative than some protective coatings. Tin also has a good level of conductivity enhancement properties (as opposed to silver which has higher conductivity) which may be of benefit to manufacturers seeking to enhance this property somewhat without adding too much to the price.
Tin has good solderability and is therefore a coating of choice where later soldering of components is required especially in the electronic fields.
Colour & Aesthetics: Tin plating has a 'whitish grey' hue and is usually applied without the layer of bright nickel used in decorative coatings - as such tin has a dull, or matt appearance.
commonly is used on lower value substrates such as mild steel or copper alloys.
Applications of Tin Plating: Examples include: Low-tech electrical or electronic components such as electronic connectors or bus bars; commercial cooking equipment; parts requiring soldering; other.
Substrates suited to this coating: Tin can be plated over most metal substrates .

27. Chrome Plating
is a very popular finish for many decorative applications, especially for the automotive and building industries in which there are many decorative trims and components. It also has industrial uses where, in conjunction with heat treated base materials it can provide a harder finish (hard-chrome).
Chrome plating is popular because it is hard wearing, bright and easy to clean. The nickel used in the coating process in conjunction with chrome provides high corrosion resistance. The nickel type used also determines the level of brightness. T
he chrome coating itself is stain resistant and abrasion resistant which is of appeal for decorative applications in heavier 'wear and tear' environments. T
here are alternative industrial uses for chrome plating (i.e. hard-chrome*), sometimes used for surface maintenance on large tools or equipment.
Applications of Chrome Plating: Automotive decals, door handles and trims, tap-ware, architectural fittings, racks, hubs & wheels, furniture and furniture trim, and many, many other items. 27

28. Silver plating
Silver plating is an electrolytic process. Its properties can be utilised for either "functional" purposes such as enhanced electronic application or corrosion resistance, or, "decorative" purposes. Silver is commonly applied over preliminary coatings of copper and nickel though depending on the application this may vary.
Benefits of SILVER Plating:
Functional - Enhances electronic and radio wave conductivity. In a "high purity" form it is possible to achieve surface silver of around 99.99% purity.
Applications of Silver Plating: "Functional" coating examples include high- tech Electrical or electronic components such as antennas, bus bars, connectors. "Decorative" applications commonly include silverware (teapots, trays, trinkets, etc), jewellery or hand crafted art pieces.

29. Nickel plating
Nickel provides the 'substance' of the coating as it predominantly provides the hardness and corrosion resistance to the surface. Though sometimes used as a 'final finish' it is more common for nickel to be applied as the "undercoat" to final finishes such as silver, gold or chrome. The nickel solution type used in the finishing process determines the level of brightness of the finished product. Some nickel solutions result in a matt or 'satin' finish.
Benefits of Decorative Nickel Plating: Nickel plating provides the finished product with hardness and protection from the elements and determines the level of brightness of the product - in fact it can be extremely difficult to achieve a bright finish without it.
Colour & Aesthetics: Nickel is a silvery colour with a "yellow/brown" hue. Nickel as a final finish can sometimes provide a closer match to some stainless steel grades - depending on the level of nickel contained in the stainless material.
Applications of Decorative Nickel Plating: As an "undercoat" nickel is used for most decorative applications. It can also be used as a final finish if required. A Class's "Restoration" divison has assisted with restoration of many early model vehicle components, traditionally nickel plated.

30. Electroless Nickel Applications of Electroless Nickel Plating:
Electroless Nickel is a chemical plating process which, unlike electroplating, does not require electrical current to deposit. Nickel is deposited to the surface metal via an 'autocatalytic' process which deposits the coating in uniform density to the surface being plated.
The Electro-less Nickel plating process has many advantages over 'electrolytic' processes in an engineering environment. The coating can be used where a hard, corrosion resistant finish is required.
A major advantage of the process is that it is possible to coat the whole surface of an item EVENLY, including internals, unlike electrolytic processes which have difficulty depositing into recessed and internal areas and can result in excessive build-ups on points, corners, etc.
Applications of Electroless Nickel Plating:
Valves, shafts, drilling equipment, rollers, dies & moulds, tooling, pumps, hardware & more. Wherever there is need to prevent corrosion, reduce wear or improve hardness and durability.

31. Plating grade plastic
Decorative plating on plastic is achieved by a metallising process specifically engineered to enable non- conductive ABS plating grade plastic to be electroplated.
Why ABS Plastic? ABS is a specially designed plastic (Acrylonitrile Butadiene Styrene) with properties suited to the metallising process enabling continuous production of high volume components.
Benefits of Plating on ABS Plastic Substrates: Moulded ABS plastic components are substantially cheaper to manufacture than metal parts. They offer adequate strength and significant weight reduction is also a benefit in some instances. After plating there is no apparent difference visually between metal and plastic parts.
Applications of Plating on ABS Plastic Substrates: Automotive decals and trim, tap- ware, furniture trim, bathroom accessories, hardware accessories, some electrical fittings and many other items.

32. Zinc plating
Zinc plating is the most common, low cost; electroplated coating that is normally applied to ferrous components to give corrosion protection. The coating can be coloured to give gold; black or olive drab coatings by post treatment. The relatively low cost, protective nature and attractive appearance of zinc make it a popular coating for nuts, bolts, washers, metal stampings and automotive parts, such as interior components and gas filters. In addition, zinc serves as an effective undercoat for paints when high corrosion performance is required. What Material Can Be Zinc Plated? Near any metal can be zinc plated but the most common are steel and iron on which it offers sacrificial protection.
Recommended uses for Zinc electroplating: Zinc plating is used where a clean, smooth, corrosion resistant surface is required. Commonly used on nuts, bolts, metal brackets. etc but it also makes an excellent undercoat for powdercoating or paint. Zinc electroplating can leave recesses on complex shaped components without sufficient zinc coating to provide corrosion protection. Finished Products can recommend other coatings that may overcome this effect.

33. Hot Dipped Galvanising
Heavy galvanizing is often referred to as batch, heavy duty or after fabrication galvanizing.
Light galvanizing is referred to as continuous, ILG (In-Line Galvanizing) or zinc electroplated.
The Australian market has a wide variety of local and imported light galvanized products readily available. (See previous slide)
Heavy galvanizing is the only galvanize finish that gives a complete coating of heavy zinc both externally and internally.
The zinc coating is typically in the range of 85µ m² or 600 gms / m² on 6mm thick steel.
Heavy galvanizing produces the maximum thickness possible relative to steel thickness, with long term protection its only objective.

34. ZINCALUME® steel
Roof sheeting made from ZINCALUME® steel is available in a range of profiles.
The zinc/aluminium alloy coating on ZINCALUME® steel
imparts corrosion resistance of up to four times the life of galvanised steel.

35. Colorbond Steel
Colorbond is the name given to a special grade of corrosion resistant high strength steel that is coated with zincalume and painted in a limited range of colorbond colours. The special corrosion resistant base metal means that any exposed edges/surfaces (due to cuts and scratches) do not cause premature corrosion failure.

36. Zincalume is for Factories: Clients thinking of the option of using zincalume steel instead of Colorbond - thinking that there would be good savings.
Colorbond is approximately $1.40 per square metre more than zincalume. But over the area of an average 120 square metre roof, it works out to be ONLY $168.00! ...And for this small sum, they will get a far superior product - and with a choice of colours too!
Zincalume is really the choice for factories which have roofs measuring many hundreds and thousands of square metres. And the price savings of using the cheaper material can be substantial here.