Laser cladding features
1.Technical Features
Laser cladding the most important feature is the heat concentration, fast heating, fast cooling, heat-affected zone is small, especially for melting between different materials have other heat sources can not match the characteristics, it is also this special heating and cooling process, in the The structure of the casting zone is also different from other cladding (such as spray welding, welding, welding, etc.) means, and even can produce amorphous, especially pulsed laser is more obvious.
This is why the so-called laser cladding has no annealing and no distortion, but I think this is just a macro view of the entire workpiece. When you do a microscopic analysis of the cladding and the HAZ, you can see another scene .
2.Equipment characteristics
Laser cladding, the current domestic use of two models: CO2 laser and YAG laser. The former is continuous output, cladding power is generally above 3KW; YAG laser pulse output, generally about 600W.
For equipment, it is difficult for the average user to eat it thoroughly. It relies heavily on the producer's service, the purchase price is high, the maintenance cost is high, the price of the parts and components is very high, and the stability and endurance of the equipment are relatively different from those in other countries. Therefore, Laser cladding machine is generally used in special fields, ordinary industrial manufacturing, maintenance difficult to benefit.
3 process characteristics
(1) pre-treatment
Laser cladding the most important feature is the heat concentration, fast heating, fast cooling, heat-affected zone is small, especially for melting between different materials have other heat sources can not match the characteristics, it is also this special heating and cooling process, in the The structure of the casting zone is also different from other cladding (such as spray welding, welding, welding, etc.) means, and even can produce amorphous, especially pulsed laser is more obvious.
This is why the so-called laser cladding has no annealing and no distortion, but I think this is just a macro view of the entire workpiece. When you do a microscopic analysis of the cladding and the HAZ, you can see another scene .
2.Equipment characteristics
Laser cladding, the current domestic use of two models: CO2 laser and YAG laser. The former is continuous output, cladding power is generally above 3KW; YAG laser pulse output, generally about 600W.
For equipment, it is difficult for the average user to eat it thoroughly. It relies heavily on the producer's service, the purchase price is high, the maintenance cost is high, the price of the parts and components is very high, and the stability and endurance of the equipment are relatively different from those in other countries. Therefore, Laser cladding machine is generally used in special fields, ordinary industrial manufacturing, maintenance difficult to benefit.
3 process characteristics
(1) pre-treatment
Laser cladding, the general only polished workpiece clean, degreasing, rust, to the fatigue layer, relatively simple.
(2) to send powder
CO2 laser power larger, generally with argon to send powder; YAG laser power is small, the general use of natural powder way. Both of these two methods basically form a molten pool in a horizontal position during cladding, and the tilted slightly larger powder can not be normally served. The use range of the laser is limited, especially the YAG laser.
(3) From the state of molten pool formation
As the laser control of high precision, constant output power, and no arc contact, so the depth of the pool depth consistency.
(4) fast heating, fast cooling
The uniformity of the formation of the metal phase is also unfavorable to the exhaust scum, which is also an important reason for the formation of stomata and uneven hardness of the laser cladding. In particular, the YAG laser tends to be more serious.
(5) material selection
Due to different materials on the absorption of different wavelength laser abilities, resulting in laser cladding material selection is more limited, the laser is more suitable for nickel-based self-fluxing alloys and some other materials, the carbide, oxide cladding more difficult.