Explaining Ionic Bombardment for Power Transformers

[EverGreen1231]

Thank you in advance for taking the time to read this thread.

I'm putting together a program that computes the performance quality of power transformers for the company I'm working for. I'm in the process of writing down a description of the DGA (Dissolved Gas Analysis) of the oil in the transformer main tank.
One of thing that isn't quite clear to me is, according to the IEE Standards, fault gases that are formed within the transformer due to low energy discharges and coronal discharges are mainly caused by ionic bombardment. Could someone give me an explanation of what ionic bombardment means? Is it similar to the process of fission?

Much obliged,
-Tyler.

 

[e.bar.goum]

When I use the phrase "ionic bombardment", I mean a beam of charged atoms impinging on a surface. This will result in defects in the material, and the modification of materials by ion beams is as very large area of research for materials scientists. This isn't like nuclear fission at all, which is where a nucleus splits into two.