Can I use 3 blades instead of 2 blades with the same pitch and dia to increase the thrust of my motor? Will it burn my motor? or it will damage my ESC? Some motors are having high torque but low rpm, others have low torque with high rpm. Is it possible to increase my thrust power without damaging the motor and ESC? will it efficient to hover my copter?
Increasing the number of blades in the props increases the amount of thrust generated but at the cost of efficiency i.e. more current will be drawn as we increase the number of blades. This is due to addition of weight and also because of increased drag, as each blade will have to cut through the turbulent air from more preceding blades which will result into lesser flight time as the battery will be consumed very quickly.
The thrust is increased due to increased surface area by the addition of extra blades which means you can lift same amount of weight with shorter dia props.
Further addition of blades slightly improves the control over the aircraft which might be required for racing multi rotor crafts or for indoor flying of smaller UAVs.
But generally speaking a two blade prop is better option as compared to three blade because we do not want to overload the motor and make it draw more current which might result into heating issues and even burning of ESCs.
You can further read about props from here to get a better understanding of the concept.