Additive manufacturing, more commonly referred to as 3D printing, is a process of creating physical parts by building them layer by layer from digital data. Additive manufacturing builds parts by adding material only where it is needed. In some systems, additional support material is used to hold the part during the build process, but the core principle remains the same. There are many different additive manufacturing processes, each building parts in fundamentally different ways. They are all categorized as additive because they share the common approach of adding material where and when it is needed, rather than removing material (subtractive manufacturing) or relying on tooling.

There are many different 3D printing technologies, each with its own advantages, limitations, and ideal use cases. These technologies are commonly categorized under the ISO/ASTM 52900 standard, which defines the main families of additive manufacturing processes. The main categories of 3D printing include: Material Extrusion Material is pushed through a nozzle and deposited layer by layer (e.g. FDM, FFF, FGF) Vat Photopolymerization Liquid resin is cured using light to form solid parts (e.g. SLA, DLP, LCD) Powder Bed Fusion (Polymer & Metal) Powder is selectively fused using a laser or energy source (e.g. SLS, SLM / MPBF) Binder Jetting A liquid binder is deposited onto a powder to bond material together (e.g. sand molds/cores, full-colour sandstone, metal) Material Jetting Droplets of material are deposited and cured layer by layer (e.g. MJP / PolyJet) Directed Energy Deposition (DED) Material is deposited and fused simultaneously using focused energy

3D printing accuracy varies depending on the process, material, and part geometry. Each technology has its own typical tolerance range, and accuracy can also be influenced by:  Part size and orientation  Material behavior during printing  Post-processing requirements  Machine calibration and condition Accuracy can also vary from OEM to OEM, even within the same process category. Higher-end industrial systems are typically more consistent and repeatable than lower- cost alternatives. In many cases, 3D printed parts are near net shape, meaning critical features may be machined after printing to achieve tight tolerances.

Choosing the right 3D printing process depends on the application, and there is no single solution that works for every part. Key considerations include: Required strength and material properties Surface finish and feature detail Part size and geometry Quantity and scalability Budget and lead time Different processes are optimized for different outcomes. For example: SLS is ideal for functional parts and batch production SLA/DLP is best for high-detail visual models MJP excels in extremely fine features and smooth surfaces Metal (SLM / MPBF) is used for high-performance, fully dense components In most cases, the best approach is to select a process based on the end-use requirements of the part, not just the technology itself. If you're unsure, reviewing your application, constraints, and goals will help determine the most appropriate solution.

3D printing materials vary significantly depending on the process being used. Each technology is designed to work with specific material types. Metal (SLM / MPBF) Metal powder bed fusion systems can process a wide range of metals. As a general rule: Materials that can be laser welded are often good candidates Common materials include: Stainless steels (e.g. 316L, 17-4PH) Tool steels Aluminum alloys Titanium alloys Some materials, such as high carbon steels, are more difficult to process due to cracking and thermal stress during printing. Material Extrusion (FDM / FGF) Material extrusion systems use thermoplastics. As a general rule: If a material can be melted and extruded, it can potentially be printed However, not all systems can process all materials. Common materials include: PLA PETG ABS Nylon High-performance materials such as PEEK Material compatibility depends on: Nozzle temperature capability Build chamber conditions Material behavior (shrinkage, warping, flow) SLS (Selective Laser Sintering) SLS is primarily based on nylon (polyamide) materials, due to their thermal stability and processing characteristics. Common materials include: PA12 (nylon) TPU (flexible) Glass-filled or carbon-filled nylons ESD-safe materials SLA / DLP (Resin) Vat photopolymerization systems use UV-curable resins (photopolymers). There is a wide range of resins available with different properties (rigid, flexible, high-temp, etc.), but: Materials are typically machine-specific Compatibility depends on the wavelength of the light source MJP (Material Jetting) MJP systems are typically closed material systems, meaning they only operate with OEM-specific materials. These materials are tightly controlled to ensure: Consistent droplet formation Reliable curing High accuracy Most systems offer a limited library of materials with varying properties. Binder Jetting Binder jetting systems are typically designed around a specific material family. Examples include: Sand (casting molds and cores) Metal powders (for sintering workflows) Gypsum-based materials (full colour printing) In metal binder jetting: Many metals can be printed But successful production depends heavily on the ability to properly sinter the material, which requires specialized equipment and expertise Key Takeaway Each 3D printing process is tied to a specific class of materials. Choosing the right material is not just about the material itself—it depends on selecting the right process + material combination for the application.

The cost of 3D printing depends heavily on the application. In some cases, it is more expensive than traditional manufacturing. In others, it can be significantly more cost-effective. When 3D printing is more expensive Simple parts that are easy to machine High-volume production where tooling is already justified Large solid parts with no design optimization When 3D printing is more cost-effective Complex geometries that are difficult or impossible to machine Low-volume production without tooling Parts requiring customization Applications where multiple components can be combined into one Key insight 3D printing is not a better way to make the same part—it is a way to make better parts. By redesigning parts to take advantage of additive manufacturing, it is often possible to: Reduce material usage Decrease weight Improve performance Reduce assembly and labor In many cases, the overall system cost—not just part cost—can be reduced.

In many applications, the value of 3D printing is not in reducing the cost of the part itself, but in improving the performance of what the part does. For example: Aerospace lightweighting A printed bracket may cost more than a traditionally manufactured part, but reduced weight can lead to significant long-term savings in fuel and operating costs Conformal cooling in tooling A 3D printed tooling insert may cost 3–4× more than a conventional insert, but improved cooling can reduce cycle times and scrap rates—delivering far greater value over the life of the tool Assembly consolidation (GE LEAP fuel nozzle) A multi-part assembly can be redesigned into a single printed component, reducing variability, improving reliability, and simplifying manufacturing There are countless examples where improving performance, efficiency, or reliability outweighs the initial increase in part cost.

The best way to get started is by understanding your application and what you are trying to achieve. This typically involves reviewing: The part or product requirements Required material properties Accuracy and surface finish expectations Quantity and production goals From there, the most appropriate process and material can be selected. If you're unsure, working with a knowledgeable provider can help you evaluate options and determine the best approach for your specific application.