Effect of laser hardening technical parameters on hardened depth of 40Cr steel

Laser hardening of 40Cr has been carried out with a 5kW CW CO2 laser,the effects of laser technical parameters on hardened depth are discussed.The results indicate that the hardened depth increases with increasing laser power or overlap of dimension of laser beam and decreasing speed and that scanning speed is more important to hardened depth than laser power.In a range of laser hardening technical parameters:laser beam diameter:3mm,laser power:1000～1200W,scanning speed:15～30mm/s,overlap of dimension of laser beam:1.0～1.5mm,a hardened depth of 40Cr no less than 0.35mm can be obtained.