Technologies
Selective Laser Melting (SLM) is an additive manufacturing process that uses a high-power laser to fully melt metal powder particles layer by layer, creating fully dense components with mechanical pro
Selective Laser Melting (SLM) is an additive manufacturing process that uses a high-power laser to fully melt metal powder particles layer by layer, creating fully dense components with mechanical properties equivalent to traditionally forged or machined parts. Parts built with SLM achieve ≥99.5% re
Selective Laser Melting (SLM) is an additive manufacturing process that uses a high-power laser to fully melt metal powder particles layer by layer, creating fully dense components with mechanical properties equivalent to traditionally forged or machined parts. Parts built with SLM achieve ≥99.5% relative density, dimensional tolerances of ±0.05–0.1 mm, and can be produced from premium materials including stainless steel, titanium, and aluminum alloys. SLM is the process of choice for complex, load-bearing metal parts where conventional manufacturing would require extensive machining or be geometrically impossible.
SLM builds parts through a precise, repeatable cycle:
This entire process occurs in a nitrogen- or argon-filled chamber, preventing oxidation and ensuring material properties remain consistent across the part.
The three most widely available SLM materials for production parts are 316L stainless steel (ASTM A276 equivalent), AlSi10Mg aluminum alloy, and Ti-6Al-4V titanium (Grade 23). 316L delivers excellent corrosion resistance and tensile strength (≥490 MPa) for medical implants, valves, and harsh-environment components. AlSi10Mg provides a lightweight alternative with tensile strength around 450 MPa and is preferred for aerospace applications where weight reduction is critical. Ti-6Al-4V achieves the highest strength-to-weight ratio (tensile strength ≥1,160 MPa) and is the standard for aerospace, medical device, and motorsport applications requiring extreme reliability.
Engineers in Cairo, Alexandria, Riyadh, Jeddah, and Dammam regularly specify these materials for applications from hydraulic manifolds to orthopedic implants to satellite brackets. Material cost, lead time, and post-processing requirements differ significantly; consult Entag's technical team during design review to optimize material selection.
| Parameter | SLM (Selective Laser Melting) | DMLS (Direct Metal Laser Sintering) | Binder Jetting |
|---|---|---|---|
| Fusion mechanism | Full powder melting (≥99.5% density) | Partial sintering + liquid phase | Binder adhesion + sintering |
| Typical tolerance | ±0.05–0.1 mm | ±0.05–0.1 mm | ±0.2–0.3 mm |
| Surface finish (as-built) | Ra 12–16 µm | Ra 12–16 µm | Ra 6–10 µm |
| Best materials | Stainless steel, Ti alloys, AlSi10Mg | Tool steel, Inconel, cobalt-chrome | Stainless steel, copper |
| Support structures needed | Yes (mandatory) | Yes (mandatory) | No |
| Typical layer thickness | 20–50 µm | 20–40 µm | 50–100 µm |
| Part strength vs. wrought | 95–100% | 95–99% | 60–80% (pre-sinter) |
SLM is the correct choice when you need near-wrought-strength parts with tight tolerances and premium materials. DMLS is cheaper for tool steel and Inconel but delivers marginally lower density. Binder jetting is fastest and requires no supports, but produces lower mechanical strength and worse dimensional accuracy—suitable only for non-structural or prototype applications.
At Entag, we build fully dense SLM parts to ±0.1 mm tolerance as standard, with capability to hold tighter tolerances on critical features via post-machining. Parts are delivered heat-treated and ready for assembly or final finishing per your CAD file specifications.
Minimum wall thickness on SLM parts is 0.4–0.8 mm. Thinner walls cause laser power to blow through the powder bed, creating porosity or voids. Keep overhangs below 45° or add support structures to anchor unsupported regions to the platform. Design horizontal holes where possible; vertical holes printed parallel to the build direction are prone to powder entrapment.
Add 0.1–0.2 mm machining allowance on critical surfaces (threads, bearing seats, datum faces). As-built SLM surface finish is Ra 12–16 µm; post-processing via CNC machining services in Egypt or bead blasting brings finish to Ra 1.6–3.2 µm. Combined with 3D printing services in Egypt, our post-processing capabilities ensure your parts meet specification. Follow ISO/ASTM 52900 terminology for additive manufacturing specifications and communicate all tolerance stack-ups, material grades, and heat treatment requirements in your CAD file annotations or design review call.
What is the minimum wall thickness for SLM parts?
SLM minimum wall thickness is typically 0.4–0.8 mm. Thinner sections risk incomplete fusion or powder entrapment. Thicker walls (≥1.5 mm) print more reliably with no risk of defects and reduce support material requirements, lowering overall cost per part.
How do I remove support structures from SLM parts?
Support structures can be removed via manual breaking (for thin lattice), sawing, EDM wire cutting, or abrasive blasting. Method depends on part geometry and accessibility. Entag handles support removal in-house—specify your preferred finish in the design review.
What surface finish does SLM achieve as-built?
As-built SLM surface roughness is Ra 12–16 µm, suitable for internal cavities and non-contacting surfaces. External, high-wear, or cosmetic surfaces require post-processing: bead blasting achieves Ra 6–10 µm; CNC finishing brings Ra 1.6–3.2 µm.
Can SLM metal parts be post-machined after printing?
Yes. SLM parts are ideally suited to secondary machining. The fully dense (≥99.5%) material machines like wrought alloy with standard carbide tools. Budget 5–15% of print time for finish machining on critical surfaces like threads or bearing bores.
What is the lead time for SLM parts from Entag?
Lead time depends on part complexity, material, and batch size. Simple parts (one-off or small batches) typically require 2–3 weeks; high-volume production may take 4–6 weeks. Quote turnaround is 24 hours after CAD file review.
Which SLM material should I choose for my application?
Choose 316L stainless steel for corrosion resistance (pumps, valves, medical devices). Select AlSi10Mg for weight-critical aerospace or automotive parts. Specify Ti-6Al-4V for maximum strength-to-weight and biocompatibility (orthopedic implants, high-performance brackets). Entag's engineering team recommends material during design review.
Ready to start your project? Request a quote on Entag — upload your CAD file and get a price in 24 hours. We serve engineers and procurement teams in Cairo, Alexandria, Riyadh, Jeddah, and Dammam with on-demand SLM metal 3D printing and post-processing. No minimum order, no setup fees.
