I am just now ready to do mine, hoping not to hit the same stubborness you have encountered. My previous Volvo mechanic told me that he uses a wheel puller to coax the bearing off the car. That would be a bit less dramatic compared to pounding on it. The other reply you got on here makes sense also as that similar to how I handled some of my other cars.

Some have splines that are locktighted while others it's rust. The best way to do it is to first, make sure that the 2 control arm to subframe bolts are still in place (along with anything else you might have removed before that holds the hub assembly in place). Spray the axle slines alot with WD-40 from both ends as best possible. Take your 36mm or US equivalant socket and thread the nut back onto the axles threads, enough so that all of the nut has threads inside but not near being tight. Now I then use an extension in the socket and pound on that very hard with a large hammer being carefull not to miss and hit your hand (yes, I've done that and it hurts). The extension end will be destroyed, flatened (unusable for an extension again) but it's better that than your socket or worse, the threaded end of the axle shaft. If the axles splines were locktighted from the factory, it takes excessive force to budge the splines so be as patient as possible. Once the splines begin to move (you'll notice the nut has gone inwards) it goes fairly easy. I then remove the 2 bolts that hold the control arm to the subframe, pry it away from the subframe and then the axle will tap out easily.