Thank you for confirming they have the same damage split.I can confirm that Imperial Hammers have the same 2:1 thermal:kinetic damage split as rails, as follows.
As noted in my recent post in this thread, in No.2 of my "Truesilver's Tests" series, back in 2015-16, I tested the above damage split and got the same outcome as Cmdr Maligno in his recent testing.
However, in No.1 of the same series, I'd already tested the total triple burst of an Imperial Hammer as doing about 8% more damage than the single shot of a c2 rail. Testing was against a vanilla shield as in those days ofc everything was vanilla. Very, very many shots were tested under controlled conditions without shield regen etc. and analysed using Windows Movie Maker.
This was, of course, before Frontier released their damage stats, hence the need for testing. Then, when in Patch 2.1, Frontier released damage stats we were able to see that each burst of an Imperial Hammer (45 damage) does indeed do about 8% more damage than a single rail (41.5 damage), or to be precise, 8.43% more damage. There have been no subsequent changes to those stats.
The additional 0.43% is well within the error margin.
Now, the above proves that Imp Hammers and Rails must have the same damage split, because otherwise my +8% would not have tallied with the subsequently revealed damage stats. The difference between kinetic (+40%) and thermal (-20%) resists on a vanilla shield is very large, so if Hammer damage had a different thermal:kinetic distribution, my testing would have yielded a result that would have seemed quite anomalously different to the subsequently revealed damage stats, rather than the same.
I don't yet own Imperial Hammers, but when I do I might take some time to run a quick test and make sure the damage split is still the same. I have no reason to believe they have changed, but in this game you never know =)