Best 3D Laser Cladding Technology Machine | Metal Deposition Processing System

Best 3D Laser Cladding Technology Machine | Metal Deposition Processing System

WHAT IS LASER CLADDING TECHNOLOGY？

Laser cladding, also known as laser metal deposition or laser melt-coating, is a new surface modification technology. Using a high-energy laser as a heat source and metal alloy powder as welding material, the laser and alloy powder act simultaneously on the metal surface to melt to form a molten pool, and then rapidly solidify to form a dense, uniform, and a controllable metallurgical bonding layer. The cladding layer has special physical, chemical, or mechanical properties, thereby significantly improving the wear resistance, corrosion resistance, heat resistance, oxidation resistance, and electrical properties of the surface of the base material.

The process parameters of the laser cladding system include laser power, spot diameter, cladding speed, defocus amount, powder feeding speed, scanning speed, preheating temperature, etc. These parameters greatly influence the dilution rate, cracks, surface roughness of the cladding layer, and compactness of the cladding parts. The parameters also affect each other, which is a very complex process. In order to control these parameters within the allowed range of laser cladding, an appropriate control method must be used.

3 key process parameters of laser cladding machine

1. Laser Power

Increasing laser power will melt more cladding metal, increasing the probability of generating pores. With increasing laser power, the depth of the laser cladding layer increases, and the surrounding liquid metal fluctuates violently, solidifies, and crystallizes dynamically so that the number of pores is gradually reduced or even eliminated, and the cracks are gradually reduced. When the depth of the cladding layer reaches the limit depth, as the power increases, the surface temperature of the substrate increases, and the deformation and cracking phenomenon intensifies. If the laser power is too small, only the surface coating melts, but the substrate is not melted. At this time, local pilling and voids appear on the surface of the cladding layer, which cannot achieve the purpose of surface cladding.

2. Light spot diameter

The cladding laser beam is generally circular. The width of the cladding layer mainly depends on the spot diameter of the laser cladding beam. As the spot diameter increases, the cladding layer becomes wider. Different spot sizes will cause changes in the surface energy distribution of the cladding layer, and the obtained cladding layer morphology and microstructure are quite different. Generally speaking, the quality of the cladding layer is better under the small spot size, and the cladding layer's quality decreases with the spot size increase. However, the spot diameter is too small, which is not conducive to obtaining a large-area cladding layer.

3. Laser Cladding Speed

The cladding speed V has a similar effect to the laser power P. If the cladding speed is too high, the alloy powder can not melt completely, which causes the high-quality-effect cladding cannot be achieved; if the cladding speed is too low, the molten pool exists for too long, the powder is over-burned, and the alloy elements are lost. At the same time, the heat input of the matrix is large, which will increase the amount of deformation.

The parameters of laser cladding machines do not independently affect the macroscopic and microscopic quality of the cladding layer but affect each other. To explain the comprehensive effect of laser power P, spot diameter D, and cladding speed V, the concept of specific energy Es is proposed, namely:

Es=P/(DV)

The irradiation energy per unit area can be considered by combining laser power density and cladding speed.

Under the condition of certain laser power, the cladding layer's dilution rate decreases with the spot diameter increase. When the cladding speed and the spot diameter are constant, the cladding layer's dilution rate increases with the laser beam power. In addition, as the cladding speed increases, the melting depth of the matrix decreases, and the dilution rate of the matrix material to the cladding layer decreases.

With the development of the mechanized industry, various surface spraying techniques (such as spraying tungsten carbide, plasma spraying, or arc welding) emerge in an endless stream.

A laser cladding machine adopts a new surface modification technology. It offers several advantages compared to conventional coating processes, including delivering a higher quality coating material with very little distortion and dilution and enhanced surface quality.

1. Laser cladding can provide an alloy layer with corrosion resistance, wear resistance, and excellent performance on the surface of the substrate, which greatly improves the service life of the workpiece.

2. High-quality laser cladding alloy layer and minimal distortion in the substrate, with almost no post-processing necessary.

3. Laser cladding has a thorough metallurgical bond to the substrate, with no peeling, chipping, or cracking, which means it will not peel or crack like plasma or thermal spray coatings.

4. Laser cladding can better control the thickness of the alloy coating and can also use multiple cladding layers to achieve various thicknesses.

5. Small heat input and deformation, low pollution, and environment friendly.

6. Easy automation and integration into CNC and CAD/CAM production environments.

Features of Laser Cladding Technology Machine

Laser Cladding Head

Continuous-Wave Fiber Cladding Laser Generator

1. The separation design of optoelectronic modules

Optical path and circuit modules do not interfere and work stably; optoelectronic modules can be directly upgraded and replaced at the client factory; easy maintenance. The separation design of optoelectronic modules

- Back reflective protection technology

Three-level back-reflection protection and fast monitoring ensure the safety and efficiency of the cladding fiber laser generator while processing high-reflective materials.

2. High power single module

The output power of a single module is up to 3kw, and the equipment integrated with the 10,000-watt laser is smaller.

3. Efficient laser technology

Electro-optical conversion rate≧35%, more energy saving

Double-Barrel Powder Feeder

The double-barrel powder feeder can realize long-distance powder transportation and meet the requirements of three-dimensional laser cladding and rapid laser prototyping. The system has a hardware failure self-detection function, which can send out alarm information at a time when a failure occurs, which is safe and reliable.

Industry Application of Laser Cladding Technology

Coal Industry

Laser cladding, laser surface treatment, and remanufacturing technologies are widely used in the coal machinery industry, which can realize the repair and remanufacturing of coal machine columns, hydraulic support cylinders, picks, worn shafts, coal mining high-speed shafts and tooth parts, and Laser strengthening of various shafts such as gears, ring gears, cranks, etc.

Metallurgy Industry

Repair and strengthen wear and tear of a metallurgical conveying roller table and various shaft parts.

Repair and strengthen various large, medium and small gear parts in the metallurgical industry.

Petrochemical Industry

Surface treatment of drilling tools, oil rig connecting shafts, vacuum pump shafts, ball valves, etc., improves wear resistance, corrosion resistance, and peel resistance.

Electric Power

Surface repair and strengthening of the steam turbine rotor, fan rotor, compressor rotor, gear shaft, and compressor screw.

Construction Machinery

Strengthening and repairing construction machinery oil cylinders, engine crankshafts, hydraulic cylinders, and other accessories to improve wear and corrosion resistance.

Shipping Equipment

Repair and strengthen engine crankshaft, marine inner bladder, valve, cylinder head, plug, and other accessories.