IRFZ44N for PWM replacing my TIP3055 BJT
The IRFZ44N has RDSON of up to ~0.0175&ohm; at a junction temperature of 25&deg;C, rising to ~0.030&ohm; at 125&deg;C. At 12.5A it would dissipate ~4.7W at 125&deg;C. So it could do it, but needs a heatsink rated at 20&deg;C/W or less (calculated here). Voltage drop at 12.5A will be ~12.5*0.03 = 0.42V, which is probably acceptable.

The 1N4004 is a mains frequency silicon rectifier diode rated for 1A max. At 50% PWM the diode would be passing half the average motor current and the same current as the supply, so its 1A current rating will probably not be sufficient. For lower loss and faster switching at you should use a Schottky diode such as the 1N5822.