Unfortunately, your rotors typically will not be covered under your Ford warranty. This is because brake pads and rotors—much like tires—are considered consumable parts. In other words, they usually need replacing due to wear and tear rather than manufacturer error or defect.
That said, your Ford warranty will cover any repairs to your vehicle that result from problems at the manufacturing plant. You’ll be able to get your rotors repaired under warranty as long as the issue was clearly caused by the manufacturer rather than the regular use of your vehicle.