Heat is the right way to go here, but did you heat the hub until it was cherry red? When I say red I mean RED (as in glowing), not just hot. It's about the only way you are going to get it off. It really needs to be completely hot all the way around so the bond between the hub and the axle will be broken. You'll probably only be beating your head against the concrete until you do, then it still may not work. In that case @BrianKnoblauch is right, replacement of the entire axle may be the only recourse.
This is on old post but hopefully someone stumbles upon it that can help. The only way I've been able to get very stubborn ones off is to make a puller. Sometimes you can have luck removing the axle nut, putting the wheel back on, and using a three jaw puller through the wheel if it has holes big enough for the jaws. If not, I made my own puller. Big piece of plate steel with a 1" hole in the middle, and two holes drilled diagonally that match up with the lug stud locations. Then, stick a regular flywheel puller, or center puller in between your flat plate and the hub, with the wrench side sticking out the center hole of your plate of course. Thread the lugs on half way, with metric bolts going through your plate using the other 1/2 of the threads, and crank that bastard off. I've always gotten them off this way. Heat the crap out of the spline area of the hub and shoot some lube on the splines as you crank to avoid killing the hub.