Table 2.
Comparison of the LMD process with Wire Arc AM (WAAM).
| Aspect | Laser Metal Deposition (LMD) | Wire Arc Additive Manufacturing (WAAM) | References |
|---|---|---|---|
| Process Description | Laser (fiber/YAG) melts wire/powder, precise layer deposition. | Electric/plasma arc melts wire, rapid layer build. | 20,21,26–28 |
| Heat Source | Focused laser, small HAZ (<1 mm). | Broad arc, large HAZ (>2 mm). | 20,21,26–29 |
| Feedstock | wire or powder; wire is cleaner and more cost-effective, powder allows for alloy mixing. | wire which is cost-effective and eliminates powder-related safety concerns. | 21,26–29 |
| Deposition Rate | 1-2 kg/h, ideal for small parts. | 5-10 kg/h, suited for large structures. | 21,26,28 |
| Precision and Resolution | High, smooth finish, complex shapes. | Lower, rough, requires machining. | 26,28 |
| Material Versatility | Ti, Al, Inconel, 304L,316L powder. | Al, Ti, steel, limited alloys. | 26–29 |
| Advantages | Precision, low distortion, clean. | High rate, cost-effective, robust. | 21,26–29 |
| Disadvantages | High cost, slower rate. | Rough finish, high thermal stress. | 26–29 |
| Applications | Aerospace (blades), medical (implants). | Marine (impellers), construction (bridges). | 21,26,28 |
| Process Stability | Precise, parameter-sensitive. | Variable, defect risk (porosity). | 26–29 |
| Environmental Impact | Cleaner with wire feedstock; powder-based LMD poses contamination risks. | Cleaner and safer. | 26–29 |