Castle ESC

I use castle create 25a esc its default calib is 50% when i calib it with radio it work well and start from zero when connect it to pixhawk its calibrate automatic again and go to 50% how i can disable auto calibrate in QGC??

QGC does not calibrate the ESC unless you tell it to. Your problem.might be something else.

when i use ESC by radio (radiolink at10) i have 1kg thrust at 50% throttle but in pixhawk i have very low thrust at 50%,

Castle autocalib doesn´t work with flight controllers the esc has to be switched to multirotor or fixed endpoints mode