The simplest and best solution is to change your code slightly, and use an array of handles:
H = gobjects(1,19); % or nan(...) for pre R2014b versions.
for k = 1:19
H(k) = axes(...)
end
and then you can trivially use indexing to access each axes.
"use = strcat('handle.tile',N) This generates the correct string 'handle.tile1' if n=1..."
I would be very surprised if that worked. It certainly doesn't when I try it:
