How can be produced a powerful punch.What muscles needs? I workout biceps and triceps,does this play a role or is clearly about technique.What should I improve?
It's been a number of years since I've studied any form of striking art, but from what I remember, it's mainly technique followed by a surprising amount of the core / trunk and lower body.
For example, one study of 100+ amateur boxers (conducted by Filiminov) used tensiometric dynamometers to determine the origin and nature of punching power. Their findings concluded that almost 40% of the power from a punch is produced by the lower body. As much as 38 percent is associated with trunk rotation. Their research confirmed that the initiation of a punch starts at the ground (feet) and travels up the legs through the hips (multiplying in force).
Taken from here.