What is the impact of synergy in erosion-corrosion and how can it be measured?

[bill nye scienceguy!]

In the condition of erosion-corrosion there is weight loss from the material by electro-chemical corrosion, impingement attack from the slurry and a third 'synergy' effect coming from the interaction of the other two effects.

My question is: what proportion of the weight loss tends to come from the synergy effect? If possible can you include a reference? I need to use this for a university report.

 

[bill nye scienceguy!]

In addition to this question, how can you make a quantitative evaluation wrt erosion if the velocity and particulate concentration of the impinging slurry are known?

 

[Astronuc]

Well, erosion results in the majority of mass loss. Corrosion for the most part involves a conversion of metal to an oxide usually. Of course, corrosion could involve some amount of dissolution (of the base metal or oxide), as opposed to the erosion or wearing of the oxide.

Oxides can be converted to oxyhydroxides or hydoxides which are more soluble.

For corrosion resistant material, there is a certain level of oxide, such that the oxide 'passivates' the metal. The oxide may prevent additional oxidation (corrosion) from occurring, or it may only slow the diffusion of oxygen to the metal-oxide interface. That usually requires some thickness of oxide and little or no porosity or cracking in the oxide layer. It also means that the oxide is more or less chemically uniform, e.g. Al₂O₃.

 

[bill nye scienceguy!]

All this is true, however it doesn't really answer my question. I suppose what I'm really looking for is a way to quantify material loss due to the erosion process, equivalent to the Faraday's law method for calculating material loss due to electrochemical corrosion.