We have wide range of coating facilities at Arc Spray Engineering which includes Arc Spray, HVOF, APS and Laser Cladding. The coating process can be selected based on the application, service environment and materials.
Please see the tables below for insights and advantages of the various processes from our years of experience in this field
| Arc Spray | HVOF | APS | Laser Cladding |
|---|---|---|---|
| Low energy consumption reduces the cost of the process: Arc spray only uses compressed air and electricity | Higher splat flattening ratio and better lamella packing | Most versatile and flexible thermal spray system | Low dilution and high purity cladding can be achieved due to highly concentrated and focused laser beam on a small area |
| Low heating of the substrate leads to low material distortion | Reduces porosity level with low degree of fragmentation | Wide range of materials such as most metals, ceramics and alloys onto many different substrate materials such as plastics, glass, metals, ceramics and composite materials | Single pass cladding is sufficient to achieve a desired chemistry, microstructure and hardness due to low dilution |
| Porosity can be minimized with optimized process parameters | Less carbide decomposition and minimal oxidation due to high droplet impact velocity and relatively colder particle stream | Broad range of powder particle sizes can be used 5-100µm | Highly concentrated and focused laser beam leads to low heat affected zone which retains the substrate microstructure and mechanical properties after cladding process |
| Custom coating alloy can be produced easily through feeding different wire materials | Formation of mixed columnar and equiaxed grains in the microstructure reduce the propagation of cracks | The high temperature of a plasma jet makes it particularly suitable for spraying coatings of refractory metals and ceramics, including ZrO2, B4C and tungsten | Minimal risk of dimensional deviation or distortion after cladding makes this process promising to achieve finish dimensions of the components with the close tolerance |
| Sacrificial corrosion coating can be made uniformly on the surface of steel | Low fraction of defects (porosity/cracks/ fragmentation), less carbide decomposition and better interlamellar cohesion leads to high hardness | Metallurgical bonding between substrate and laser clad layer improves the bond strength, abrasion resistance and withstands high direct impact load | |
| Fewer health and safety risks due to simple process - No harmful gas, no high energy and no fine powder | Unlikely to tear off, fracture and spalling of laser clad layer by any external physical load or stress due the complete metallurgical bonding | ||
| Significantly low porosity prevents the penetration of highly reactive corrosive liquids/gases and protect the substrate materials from any catastrophic failure | |||
| As-mixed elemental powders (rather than pre-alloyed) can be used in laser cladding to achieve desired chemical composition of any desired alloys (in-situ alloying) |
Properties of Arc Spray coating materials from our experience
| Coating Materials | Bond type | Porosity (%) | Bond Strength (MPa) | Suitable Service Environment |
|---|---|---|---|---|
| 95Ni-5Al | Mechanical Bond | 0.3 | 67 | Bond coating |
| 420SS | Mechanical Bond | 0.3 | 66 | High strength, high elongation, low shrinkage, and little tendency to crack on the material |
| Copper | Mechanical Bond | 0.5 | 18 | Antibacterial copper coating on Stainless Steel |
| Aluminium | Mechanical Bond | 6.3 | 30 | Protection of steels from aqueous corrosion |
| Aluminium-Bronze | Mechanical Bond | 5 | 47 | Reduce deterioration, wear, and marine corrosion on ship propellers, pumps, shafts, pipes, and bushings |
| Pure Zinc | Mechanical Bond | 5 | 26 | Galvanizing iron and steel against corrosion |
Properties of HVOF and Plasma Spray coating materials from our experience
| Costing Materials | Bond Type | Porosity (%) | Hardness (HV) | Suitable Service Environment |
|---|---|---|---|---|
| Cr3C2-NiCr | Mechanical bond | 1.50 | 1000 | Wear and oxidation resistance at high temperatures. Excellent sliding and abrasion resistance, Erosion / Corrosion and good cavitation corrosion resistance |
| Cr2O3 | Mechanical Bond | 6.6 | 1200 | When corrosion resistance is required in addition to abrasion resistance |
| Cr2O3-TiO2 | Mechanical Bond | 3.7 | 950 | High Corrosion, Abrasion and Galling resistance |
| 88WC-12Co | Mechanical Bond | 1 | 1200 | Wear, cavitation erosion (CE), and corrosion |
| 88WC-12Ni | Mechanical Bond | 1 | 1200 | Excellent corrosion, abrasion and sliding wear resistance |