FDM is the abbreviation for Fused Deposition Modeling(fdm). In FDM, material (in this case: thermoplastics) is deposited in layers to create a 3D printed object. During printing, the plastic filament is fed through a hot extruder where the plastic gets soft enough that it can be precisely placed by the print head. The melted filament is then deposited layer by layer in the print area to build the workpiece.
FDM printers typically use PLA or ABS filament, some can even handle nylon and a variety of PLA blends (mixed with wood, ceramics, metals, carbon fibre, etc.). Filaments are available in various colors.
SLA is the abbreviation for StereoLithoGraphy process(SLA). Like FDM, SLA is an additive method: Models are built layer by layer. SLA, however, uses a curable photopolymer – typically a liquid resin – that is hardened by applying focussed light or UV light (this process is called curing). SLA printers usually build the models from top to bottom, the build platform lifts the model upwards, out of the resin bath. SLA printers have only a limited choice as the resins are proprietary and cannot be exchanged between printers from different makers.
When to use FDM
When precision and surface finish are not crucial
When to use SLA
When intricate details and/or a very smooth surface finish is crucial
When strength and durability of the model is not crucial (models made from resin may suffer when exposed to the sun for extended periods)
For creating molds for casting to facilitate mass-production (e.g. by 3d printed jewelry or toy makers)
fused deposition modeling advantages and disadvantages
used for Low cost, easy availability, low cost maintenance but can't use when high requirement of Mechanical Strength, Surface Finish.
Stereolithography (SLA) advantages and disadvantages
Good quality finish, mechanical strength. Expensive when compared to FDM. As these parts are UV cured, long-term exposure to sunlight can reduce mechanical strength. 3d printer technology vadodara ahmedabad surat rajkot gujarat india