Are forged wheels better (stronger or more durable) than the cast ones?
In general, forged wheels are more crack resistant than cast wheels are; though modern pressure-pour cast wheels make that difference very negligible. Cracked wheels are quite rare in either instance (in my time at BNSF's plant, we produced well over a half-million wheelsets using nearly a million wheels from 4 suppliers and I can count the number of catastrophically cracked wheels on one hand), and the added cost for a forged wheel, even if it were better, generally isn't offset by the large volumes of wheels that the freight railroads need. You would have to avoid several wheel-caused major derailments every year just to justify the added cost, and there just aren't that many wheel-caused derailments happening. Barring any really horrible train-handling, wheels will wear out long before risk of cracking becomes a significant concern, plus they are ultrasonically tested for cracks whenever they are turned.
Forged wheels are the predominant choice for passenger operations where the volume of wheels being used isn't as much of a concern and where the risk of cracking, however small it may be, is not worth the risk of a catastrophic derailment. The last thing a passenger operator wants is for a lawyer to ask why they didn't spend the extra $100 on a "better" wheel that could have prevented a derailment,regardless of how much "better" said wheel may or may not be.
Overall, just general quality of the steel used to produce wheel means infinitely more than the method used to produce it.
