How to Identify Defects in 3D-Printed Materials and Improve Print Quality

3D printing in advanced manufacturing is enabling faster prototyping, customisation and production of complex geometries not possible using traditional methods. Material waste is reduced and development cycles are shortened making it especially valuable in aerospace, medical devices and precision engineering. 

However, there is a need for need to maintain consistent part quality, structural integrity, and repeatability, especially when novel materials are used to achieve a specific property. 

ATA Scientific offers a series of analytical techniques used for certifying the quality of feedstock materials and manufactured products. Measuring properties like particle size, particle shape, elemental composition, and structural analysis can help to identify defects and improve print outcomes.

Common 3D Printing Defects and Their Causes

• Layer delamination – when layers of a print separate from each other resulting in cracks and gaps in the print due to poor layer adhesion.  
• Porosity and voids – When small holes or trapped air occurs inside the printed part due to moisture in the filament, incorrect extrusion or poor melting. 
• Warping and curling – when corners or edges lift off the print bed usually due to uneven cooling or poor bed adhesion. 
• Incomplete fusion – when adjacent layers or tracks fail to fully bond caused by low print temperature, insufficient energy input or misaligned layers. 
• Surface roughness and inconsistent finishes – when uneven bumps on walls result due to overheating, inconsistent extrusion, or retraction issues.
• Dimensional inaccuracy or distortion – when layers are misaligned creating a step effect. This may be caused by loose belts, mechanical slip or sudden movement.

Defect	Cause	Impact on part performance
Layer delamination	Poor layer adhesion (low temperature, cooling too fast, or poor bonding between layers)	Reduces mechanical strength
Porosity and voids	Moisture in the filament, incorrect extrusion, poor melting, or trapped gas	Reduces density, strength and can cause leaks in fluid handling applications
Warping and curling	Uneven cooling, poor bed adhesion or large temperature gradients	Causes dimensional inaccuracies and print failure
Incomplete fusion	Low print temperature, insufficient energy input or misaligned layers	Creates weak bonding layers that may lead to fracture
Surface roughness and inconsistent finishes	Overheating, inconsistent extrusion, or retraction issues	Reduces the aesthetic quality and can prevent tight seals
Dimensional inaccuracy or distortion	Mechanical issues (Loose belts, mechanical slip or sudden movement)	Parts fail to meet tight tolerances that may lead to assembly issues

Why Analytical Techniques Are Essential

Analytical techniques are essential because they remove the guesswork – they give you the ability to see, measure and understand what is actually happening inside your materials, processes and final products. Analytical techniques provide quantitative data for precision decision-making during troubleshooting, certification and process validation. 

Technique	What it is	What it measures	Application in 3D printing	Benefits
Optical Imaging	Light microscopy to inspect particles or surfaces	Particle size, shape and surface defects	Checks powder morphology and detects irregular shapes or agglomerates	Simple, visual quality control of powders and printed surfaces
Scanning Electron Microscopy (SEM)	High resolution electron imaging of particles or surfaces	Microstructure, Morphology, Porosity, Particle size and elemental analysis	Detects voids, incomplete fusion, poor bonding or contaminants. Analyse the quality of feed powder for optimal recycling.	Reveals defects and contaminants not visible using optical microscopy. Reduces costs of manufacture by monitoring the quality of recycled powders.
Laser Diffraction	Light scattering technique for particle size analysis	Particle size distribution	Ensures consistent powder feedstock quality and flowability	Rapid, reproducible, wide size range measurement
BET Surface Area and porosity analysis	Gas adsorption to determine surface area and pore volume	Specific Surface area and porosity	Evaluate powders for surface activity and porosity	Critical for understanding powder reactivity and density
Mercury Porosimetry	Intrusion of Mercury into pores under pressure	Pore size distribution and total porosity	Assess pore structure of printed parts and powder beds	Provides detailed pore analysis across a wide size range
Powder Rheology	Measures powder flow and dynamic behaviour under stress	Flowability, Cohesion, Compressibility	Predicts powder handling, spreading, packing in AM	Optimises reliability and reduces print defects

SEM-EDS (e.g. Phenom XL SEM)

The Phenom ParticleX AM is a specialised high-resolution desktop scanning electron microscope (SEM) dedicated to optimising AM metal powders and final product quality. By combining an imaging resolution of <8nm and magnifications up to 200,000x together with X-ray analysis (EDS) for elemental composition, properties such as structural integrity, print resolution, surface uniformity, phases and the presence of impurities or defects can be determined to contribute unique insights not possible with other systems. A scanning area of 100x100mm, grants a large degree of freedom to image and assess the size and shape of whole parts or sections of a larger component simultaneously. This fully integrated system is simple to operate and eliminates the need for outsourcing for quality checks, speeding up time-to-market. 

Morphologi 4-ID (Raman + particle imaging)

The Malvern Panalytical Morphologi 4 is an automated static image analysis system that provides statistically robust particle size and shape data, offering deeper insight into both sample and process. By imaging tens to hundreds of thousands of particles, it delivers both quantitative and qualitative analysis—an advantage over techniques like SEM, which are typically qualitative and analyse far fewer particles.

In additive manufacturing, long build times make failures costly, and the quality of the powder bed—controlled largely by particle size and shape—directly affects part performance. Characterising these properties allows manufacturers to anticipate potential failures and refresh powder before issues arise. Automated image analysis, such as the Morphologi 4, provides high-quality, statistically relevant morphological information, combining the benefits of dynamic imaging and SEM in a single technique.

Laser Diffraction (e.g. Mastersizer 3000+)

The Malvern Panalytical Mastersizer 3000+ series is designed for particle size analysis, while Insitec provides particle size measurements in real time. Combined with the Hydro Insight imaging accessory for the Mastersizer 3000+, both particle images and quantitative particle shape data can be assessed.

The particle size distribution of metal powders is an integral and defining parameter that must be monitored to ensure that batches of material are within specification and can provide the desired in-process behaviour and finished product performance. Laser diffraction is both a fast and efficient method for measuring the particle size distribution of metal powders over a very wide dynamic range in both dry and wet dispersions. Closely matching results between dry and wet measurements of the same sample can be obtained, and comparing the two allows the primary particle size, and indeed the whole size distribution, to be validated.

BET Surface Area and Porosity Analysis

Micromeritics offers a range of instruments that apply the Brunauer–Emmett–Teller (BET) theory to measure surface area. BET surface area is a method that calculates surface area based on the quantity of gas molecules or atoms that form a single layer on the surface. This is a critical parameter in 3D printing powders where flowability, sintering behaviour, and reactivity depend on available surface.

• TriStar II Plus – A versatile, three-station surface area and porosity analyser ideal for routine BET measurements of metal and polymer powders.
• ASAP 2460 – A high-throughput, expandable system designed for advanced surface area and pore structure analysis with higher sample volumes.
• 3Flex Surface Characterisation Analyser – A flexible research-grade platform for precise surface area, pore size distribution, and chemisorption studies, suited for developing new AM feedstocks.

By providing accurate BET surface area data, these instruments help manufacturers optimise powder quality, packing density, and final part performance.

Mercury Intrusion Porosimetry (MIP)

Micromeritics provides advanced Mercury Intrusion Porosimetry (MIP) instruments that measure pore size distribution, total porosity, and pore connectivity — key factors influencing the density, strength, and performance of 3D-printed parts.

• AutoPore V Series – The industry standard for MIP, offering a wide pressure range to characterise pore sizes from nanometres to hundreds of microns. 

Helium Pycnometry (True Density Measurement)

There are a number of important density parameters that affect the sintering kinetics of the powder bed and the porosity and mechanical properties of the final product. Two good examples are the apparent density, describing the density of a porous material excluding any open pores, and the tap density, which is a measure of how well the powder particles pack together. 

These characteristics can be studied using the Micromeritics Accupyc Advanced Gas Pycnometer helium pycnometer and GeoPyc envelope/tap density analyser. These instruments are non-destructive and are also able to show the total porosity of the metal powder when used together.

Powder Rheology (e.g. FT4)

The bulk properties of powders, notably flowability but also packing behaviour—a critical characteristic for AM—are influenced by the properties of the constituent particles but not predictable from them. The quantification of bulk powder properties therefore relies on measurement. 

The FT4 Powder Rheometer from Freeman Technology (a Micromeritics company) measures dynamic, shear, and bulk powder properties. By applying all three bulk powder testing techniques, users can generate the information needed to securely differentiate powder samples in a relevant way and identify poor performers. This is a valuable capability that enhances the efficiency of many operations.

Optimising 3D-Printed Materials

Analytical techniques are essential for optimising 3D-printed materials. Methods like BET surface area analysis, mercury porosimetry, and powder rheology provide insights into powder quality, porosity, and flow behaviour, while SEM, optical imaging and laser diffraction ensure product quality and uniformity. Together, these tools help reduce defects, improve part performance, and enhance reliability in additive manufacturing.

Real-World Use Cases (Optional Enhancements)

Certifying feedstock materials is crucial for ensuring the quality, safety, and performance of 3D-printed parts, especially in regulated industries like aerospace and medical devices. Comprehensive materials characterisation—including particle size, shape, and elemental composition—is essential for meeting existing standards and developing new ones. 

Analytical instruments, such as the Mastersizer 3000+ series for particle size analysis and Morphologi 4 static image analysis system are cited in ISO/ASTM 52907: Additive manufacturing — Feedstock materials — Methods to characterise metal powders. This certification process helps manufacturers comply with regulations, optimise feedstock quality, and support the adoption of additive manufacturing technologies.

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Internal Links to Feature

Phenom XL SEM
Morphologi 4-ID
Mastersizer 3000+
FT4 Powder Rheometer

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