The Low Energy Welding (LEW) is a direct current electrode positive (DCEP) micro-arc welding process, where high current, short duration pulses facilitate the flow of electrons from the substrate to the electrode. The flow of electrons interacts with gaseous ions in the intermediate distance forming a plasma arc. Material is deposited as molten material from the electrode, impinging on the substrate forming a metallurgical bond. The material is deposited via a moving applicator and ground, which transfers the electrical signals and facilitates relative motion through the use of rotation, linear motion or vibration to prevent the electrode sticking to the surface.
Huys designs, manufactures, sells, and supports low energy welding equipment (LEW) which provide the following capabilities:
- True metallurgical bond with substrate
- Substrate remains near ambient temperature; reduced or no HAZ, eliminating distortion and stress
- Micro-scale additive manufacturing process
- Dissimilar materials can be joined
- Produces consistent, thin layers
- Surface modification for hardness, wear resistance, corrosion resistance, friction, etc.
- Overlay for repair worn, corroded, defective components
- Shielding gas is applicable to eliminate oxidation in the process
- Potable for field operation
- Applicable for integration of automated system
Here is an introductory video to the LEW process:
Example Application 1: Surface modification of Stainless Steel with Molybdenum coating for corrosion resistance
Mo coated 304 stainless exhibits excellent corrosion resistance to 5% NaCl solution. It corrodes 350 times slower than 304 SS, and four times slower than DSS 2205.
Example Application 2: Repair of 6061 Aluminum Alloy
6061 Aluminum is repaired with the same material using LEW process.