Post on 31-Mar-2018
7. It is required to drill 0.3 mm diameter holes in a nickel sheet using a pulsed Nd:YAG 2nd harmonic laser with a 9 kW peak power output. How long will it take to reach the melting point on the top surface? (b) To reach the boiling point at the surface so hole drilling can begin? k = 90 W/m K, C = 420 J/kg K, α = 2.28x10-5 m2/s, R = 0.65 ρ = 8900 Kg/m3, Lv = 6.47x106 J/kg, Tm = 1700 K, Tv = 3110 K