There are a number of surface treatments which go under the generic term ‘phosphating’, but not all are used for the same purposes and equally not all will be potentially of use to us as engine designers or in specifying parts which will increase performance or reliability.
Phosphate is itself not a substance, but a negatively charged ion which may be found in solutions in a number of forms. The form which we might remember from chemistry (if we haven’t used selective recall to blank chemistry from our memory) is PO4, Read more…
Nickel plating is a common process, but there are two main methods of producing a thin layer of nickel on the surface of a metallic object. The first is to use a traditional electroplating process whereby the parts to be plated are part of an electric circuit and form the cathodes. A rod of the plating metal is used as an anode. These are immersed into a bath of electrolyte commonly containing a salt of the metal to be plated. In the case of nickel plating, the salt used is Nickel Chloride. Quite often with electroplating, there are two or even three plating processes used for the best results, 
During research for a forthcoming Race Engine Technology magazine article, Wayne Ward discussed the matter of coatings as applied to racing engine pistons with a number of the well-known suppliers, designers and manufacturers of racing pistons. The more specific point of polymer coatings in racing engines has been recently examined on the RET Monitor website, and the application of these to racing engine pistons was discussed. The focus of the discussion of 
The use of polymer coatings in racing engines has been widespread for many years, but is to some extent being displaced by the newer generation of coatings such as titanium nitride, chromium nitride and DLC as examples. In a lot of circumstances the newer coatings are an improvement, but the coatings rely on the fact that there will be no significant deformation of the coated surface, otherwise the thin coating, which itself is brittle in comparison to the underlying substrate, can craze and flake off. Debris thus caused can, in some circumstances, go on to cause more serious failures elsewhere in the 
As far as threaded fasteners are concerned, there are a large number of coatings which can be applied, and in doing so we are generally seeking to address one of a small number of issues, the main ones being:
Whilst DLC seems clearly to be the favourite coating at the moment, there are some applications where it isn’t necessarily favoured, for various reasons.
There are a very wide range of coatings which are employed in motorsport engines nowadays, and Formula One has been at the forefront of this development for many years. The moot point of excessive budgets is the reason that Formula One has been able in many cases to be a guinea-pig for these exciting technologies and, owing to this development coatings such as DLC are now finding widespread use on series production cars. The aim in these production car applications is to decrease friction and thereby increase efficiency and economy - these coatings are proving a useful tool in the drive to meet ever more stringent emissions regulations. 
One of the more interesting uses of coatings is to apply solid lubricants as a substitute for liquid lubricants. The solid lubricant that is used is normally a complex mixture that can include silver, molybdenum and various binding compounds.
Finding a material that fulfils all of the performance demands especially in a race engine is an almost impossible task. The result has been the growth in the use of coatings, used either to protect the load bearing core or to reduce frictional losses or both. Perhaps the best known are the various carbon and graphite coatings (often called DLC for diamond like coating) where a super thin layer of as little as 5 microns is deposited onto a finished surface using some form of vapour deposition. The results are dramatically reduced friction and extended part life, allowing the use in many cases
Several firms now offer specialty engine coating systems for use by individual builders and engine shops for a variety of applications. Common usages include thermal barriers, dry film surface lubricants, and anticorrosion coatings. In some cases, coatings can serve two functions, such as thermal barrier finishes for exhaust systems that also act as rust preventatives when applied to a mild steel exhaust header.
