Why does the noise become louder after adding hydrogen gas during plasma spraying

       

Plasma spraying uses argon and hydrogen. The noise after arcing with argon is not too big. After adding hydrogen, the noise becomes so loud that the ears can't stand it. Why is this? ?

Sound is produced by vibration, which was learned in high school physics. The sound becomes louder because the vibration increases, which is called the increase in amplitude in physics.



The principle of plasma spraying is that argon gas is ionized in the spray gun to generate an arc. Due to the structure of the plasma spray gun, the arc is compressed by mechanical compression, thermal compression and self-magnetic compression in the spray gun. Therefore, the energy density is high, the temperature is high, and the speed is fast.



Without hydrogen addition, when the arc is ejected from the spray gun, the surrounding air will vibrate, and the noise will be much larger than that of plasma arc welding and argon arc welding.



After adding hydrogen, the enthalpy value of the plasma arc is increased, the voltage and thermal power of the plasma arc are increased, the speed of the plasma arc is higher, and the interaction with the surrounding air is more intense, so the noise is larger.