It depends on 2 factors quantity & complexity of parts.

For < 10 parts DMLS is cost effective. When our requirement is mass i.e > 1000 casting will be cheaper.

For simple geometries like a 50 mm Dia x 50mm Length shaft DMLS cost 15,000 bucks. where as in casting or machining it may costs max 2,000 bucks. So for complex geometries DMLS will be cheaper.

Costing is divided in 3 steps. Pre-processing, 3D printing and post processing. Pre-processing activity includes Designing, part feasibility, Reverse Engineering. Secondly, in the printing phase, the cost is dependent on number of factors such as build hours, support structure required, material, orientation of part etc. Finally, in the post processing phase, activities such as heat treatment, surface finish ,CNC machining, EDM etc activities do contribute. Every part doesn’t have to go through all above mentioned activities. Number of activities depend on case to case.

3D printed parts produced with DMLS process are quite accurate. This process can achieve near net shape of a part with 0.2 mm (200µm) accuracy. Additionally, CNC machining can be done for further improvement up to 5-10 µm.

Parts have Ra values ranging from 7-12 µm depending on the material, but we can alter the value by post processing activities. These activities are capable of producing ‘Matt Finish’ and ‘Mirror surface finish’ where matt finish hardly removes any material from the surface, around 200-300 mg. However, mirror surface finish needs 0.5-1 mm additional stock for achieving 1-2 Ra value. Matt finish can achieve up to 3-5 Ra.

In most of the cases, heat treatment is compulsory. During metal 3D printing process, residual stresses generated within the part geometry can lead to product failure while in application, and therefore, stress relieving heat treatment cycle is a must for functional parts. On the other hand, parts which are merely showpieces/non-functional can be delivered without being heat treated.

Threads have several over hangs where non removable supports were generated & pitch also cannot be maintained in printing.

Recommended process is, printing a plane hole without threads & later doing tapping.

Inert atmosphere is needed while sintering metal powders to avoid oxidation process.To maintain inert atmosphere we use Argon or Nitrogen gases.

In DMLS, chamber temperature will be of max 200°C. A 400 watt laser exposes on loose powder & generates 1500 – 2000 °C at 80 microns dia spot.

After DMLS printing there are a series of secondary process involved which comes time.

Below mentioned are series of steps we do in DMLS printing process.

1. CAD data preparation
2. Machine preparation
3. DMLS printing
4. Machine unloading
5. Powder cleaning
6. Heat treatment
7. Support removing
8. Part detaching (EDM wire cut)
9. Bead blasting
10. CNC machining
11. Polishing