The ductility of 3d printed parts – to printing orientation and material choices – which worries startups and mid-sized firms. That’s because low ductility can cause 3d printed parts to fail, which costs more to produce and slows time-to-market. That’s key for regulatory compliance in aerospace and automotive, for example. This article will discuss novel approaches to overcome these limitations and enhance the ductility of 3d printed parts.
What is Ductility?
Ductility is how much a material can be deformed by stretching or drawing. This property plays an important role in the performance and use of 3D printed parts. Ductility, in terms of 3D printing, is important for printed parts. The standard measure of ductility is tensile testing, where a material is pulled with ever-greater force until it breaks.
Ductility can be measured using two primary indicators: elongation and reduction in area. For instance, if a metal bar elongates 10% before fracturing, then its ductility is 10%.
1. Beyond Bending
Traditional bending tests are not the best way to measure ductility. Other measures like tensile testing and impact resistance offer a deeper insight into a material’s ductility. Ductility is influenced by things such as material composition and microstructure — parameters that can be optimized through material selection and design.
Knowing how ductility affects a material’s ability to resist deformation and failure is key to understanding 3D printed part performance and reliability.
2. The Brittle Contrast
Ductility vs Brittleness Ductile and brittle materials have different mechanical properties, with ductile materials able to endure significant deformation prior to failure, while brittle materials tend to fracture abruptly. Brittle materials crack or shatter in response to stress and deformation, something that can have serious consequences on the performance and reliability of 3D printed parts.
There are significant challenges in working with brittle materials in 3D printing, which need specialized printing and handling to reduce chances of failing.
3. Measuring Deformation
Measuring deformation in 3D printed parts is crucial for evaluating ductility, and various methods are available, including strain gauges and optical methods. Accurate deformation measurement is essential for optimizing material properties and print settings, as it allows for the identification of areas where the material may be prone to failure.
Deformation mechanisms, such as necking and shear banding, are closely related to ductility and can provide valuable insights into a material’s behavior under stress.
4. Visualizing Failure
Visual inspection is a useful measure for the ductility of 3D printed parts, as you can see if the material has been deformed or damaged. Knowing failure modes and mechanisms in ductile materials is crucial, as it helps you identify defects and optimize your print settings!
Techniques such as microscopy and imaging can be used to visualize failure, providing a detailed understanding of the material’s behavior under stress. Ductile materials like copper have better mechanical properties like tensile strength and toughness.
Why Ductility Matters in 3D Printing
That’s why ductility is so important when it comes to 3D printing parts — it means that printed materials can bend without cracking, which is critical if you’re printing something that will experience some tension. Such a property is crucial to fields like aerospace and automotive, where 3D printed parts are implemented in high demand applications.
The importance of ductility in 3D printing cannot be overstated, as it directly affects the performance and lifespan of printed parts. For example, two perennial problems in 3D concrete printing (3DCP) are low tensile strength and a lack of ductility in non-reinforced members.
Impact Resistance
There is a strong connection between ductility and impact resistance in 3D printed parts. In aerospace and automotive applications, impact resistance is crucial, and ductility is key to the safety and reliability of 3D printed components.
You can use drop testing or impact testing—methods of measuring impact resistance—to determine how materials stand up to different types of loading and stress. Designing for impact resistance is about knowing ductility and how it relates to material properties.
That’s where ductility comes in, the cornerstone of impact-resistant design. For instance, introducing materials with better ductility, like carbon fibers, can boost printed structures’ flexural strength. After all, what does it matter that something is ductile when 3D printing it!
Failure Warning
Ductility matters because, in 3D printing, predicting and preventing failure for parts is crucial, and ductility can be used as a signal pointing to potential failure. Ductility can identify early indications of failure, including cracks and deformation, that can be remedied prior to catastrophic failure.
Visual inspection, non-destructive testing, and mechanical testing are methods for identifying early signs of failure. Failure analysis is fundamental in understanding the correlation between ductility and failure, as it allows you to pinpoint the underlying causes of failure and devise methods for enhancement.
Functional Prototypes
The role of ductility in functional prototyping and testing is significant, as it enables the creation of complex structures that can withstand various types of loading and stress. It is important to test for ductility in prototype development, so you know your printed parts will be up to the task.
Practical ways to print ductile functional prototypes include iterative design and testing, where you iteratively refine your designs based on test results to achieve optimal ductility. For example, a high ductility can be achieved in 3D printed HEAs with a hierarchical structure, which imparts a high tensile elongation of 34%.
The PR-5CB resins exhibit improved mechanical properties such as tensile strength and toughness, both of which demonstrate enhanced ductility.
Factors Influencing Ductility
Ductility in 3D printed parts is a crucial trait that influences their capacity to endure strain, particularly in flexible 3D printing materials. Factors affecting this property include material choice, print parameters, part geometry, and post-processing techniques, all essential for optimizing the tensile properties and overall strength of additive manufacturing technology.
Material Choice
Material choice is key to ductility. All materials aren’t ductile and some are better suited than others. For example, aluminum and copper are highly ductile, whereas ceramics and glass are not. The techniques for measuring ductility are tensile testing and impact testing.
Material selection for ductility includes the choice of material and optimization of material composition.
-
Material properties like grain size and microstructure influence ductility. For instance, smaller grain sized materials have more ductility.
-
Fiber addition for ductility in 3D concrete printing is a solution route that has been investigated, with scientists incorporating 3–6 mm basalt, glass, and carbon fibers to a printable blend.
-
Use of various fibers like steel, glass and polymer fibers.
-
The length and volume of fibers can play a role, with researchers comparing different glass fiber lengths (3, 6 and 8 mm) and volumes.
Print Settings
Among the most important factors for ductility are print settings. Temperature, layer thickness and print speed are a few of the important print settings that influence ductility.
The effects of different print settings on the microstructure and mechanical properties of 3D printed parts are summarized in the following table:
|
Print Setting |
Effect on Microstructure |
Effect on Mechanical Properties |
|---|---|---|
|
Temperature |
Grain size and orientation |
Strength and ductility |
|
Layer Thickness |
Porosity and density |
Strength and toughness |
|
Print Speed |
Crystal structure and defects |
Strength and fatigue resistance |
Part Geometry
Part geometry is another important consideration. Part design can influence where stress and strain accumulates resulting in different ductility values.
Fillets and rounds to optimize part geometry for ductility. Part geometry is important because it minimizes stress concentrations and encourages uniform deformation.
Print Settings
Optimizing print settings for optimal ductility involves adjusting temperature, layer thickness, and print speed to achieve the desired microstructure and mechanical properties.
You can do so through trial and error or with the help of simulation tools to forecast the impact of various print settings.
Part Geometry
Designing parts for good ductility implies designing for good stress and strain distribution. You can do this by using CAD software to simulate the part under loading.
Post-Processing
Post-processing methods, including heat treatment and machining, impact ductility. Heat treatment will change the microstructure, and thus ductility.
Machining can introduce defects and stresses. Optimizing post-processing for optimal ductility involves selecting the appropriate techniques and parameters to achieve the desired properties.
Need a 3D Printed Part That's Durable, Not Brittle?
Our AI-powered platform helps you select the right material and optimizes print settings to maximize ductility and impact resistance.
Get Your Durable, High-Ductility 3D Printed Parts.
The Ductility-Strength Trade-off
The ductility-strength trade-off means that as a material becomes stronger, it tends to become less ductile. Such a trade-off plays a vital role in 3D printed parts. Typically, strength materials tend to be low ductility and vice versa.
For example, the very high strength aluminum alloys with a higher silicon content can be quite brittle, cracking and fracturing under stress.
The beauty of the ductility-strength trade-off lies in its flexibility. In 3D printing, you can effect the ductility-strength trade-off via material and design choices. For instance, it was found later in the researches that some alloying elements, like silicon, can influence the ductility-strength trade-off in aluminum alloys.
Moreover, the microstructure determines ductility and strength with some microstructures exhibiting a better balance between the two. The ductility-strength trade-off can be impacted by the presence of defects like porosity, necessitating prudent material selection and design.
Evaluating the Ductility-Strength Trade-off
The following table summarizes common methods for evaluating the ductility-strength trade-off in flexible materials and titanium alloys.
|
Method |
Description |
|---|---|
|
Tensile testing |
Measures the ultimate tensile strength and elongation at break |
|
Charpy impact testing |
Evaluates the impact toughness of a material |
|
Microstructural analysis |
Examines the microstructure of a material to identify potential defects or weaknesses |
|
Computational modeling |
Simulates the behavior of a material under various loading conditions |
Optimizing the Ductility-Strength Trade-off
Maximizing the levers in the ductility-strength trade-off for your application is key in 3D printing. Some processing methods, like laser powder bed fusion, can generate materials with enhanced ductility and strength.
Heat treatments like annealing can get involved in the ductility-strength trade-off, with some studies demonstrating the ability of certain heat treatments to improve ductility at the expense of strength.
The ductility-strength trade-off isn’t always a simple trade-off — some materials are both highly ductile and highly strong in certain circumstances. For example, studies proved that equal channel angular pressing and high-pressure torsion could attain a great trade-off between ductility and strength.
Designing for Ductility
Designing for ductility in 3D printed parts is crucial to ensure the material can withstand stress and strain without breaking. Ductility is the degree to which a material can deform before breaking and it’s crucial in many applications such as construction, automotive, and aerospace.
The importance of designing for ductility lies in its ability to improve the overall performance and safety of 3D printed parts. By designing for ductility, manufacturers can make parts that are less likely to crack and break — saving them millions of dollars and making their products more dependable.
Strategic Orientation
Strategic orientation is important to the ductility of 3D printed parts. The part’s orientation can impact the stress and strain distribution, and good orientation can reduce the likelihood of cracking and breaking.
For instance, in 3D printed ECC, the fiber orientation can have a major effect on tensile ductility. By orienting the fibers in an optimized manner, they can get better ductility and strain capacity.
Ways to optimize orientation involve computational modeling of the stress and strain distribution of the part and using this to tune printing parameters to achieve optimal fiber orientation.
The employment of such moderately low fiber volume fraction, like less than 2% PVA or PE fibers, can enhance the ductility of 3D printed components. This is due to the fibers’ ability to help absorb stress and strain, thus minimizing cracking and breaking.
The use of supplementary cementitious materials, like Fly ash (FA) and Blast furnace slag (S), offers the potential for partial cement substitution and reducing the cement content applied in ECCs and different concrete mixes.
Fillets and Rounds
Fillets and rounds are key in dictating ductility in 3D printed parts. Fillets and rounds can aid in stress concentration reduction, which can cause cracking and breaking.
Designing parts with optimal fillets and rounds can increase the ductility and strain capacity of 3D printed parts. For instance, fine aggregates have been adopted for ECC over coarse aggregate to get greater strain capacity and multiple cracking with <60 μm.
Even the shorter length fibers, for example 8 mm, could obtain acceptable printability and increased ductility.
Stress Concentrators
Stress concentrators can kill the ductility of 3D printed parts. Stress concentrators, like sharp corners or sudden transitions in geometry, can develop high stress concentrations, which in turn can cause cracking and breaking.
By identifying and mitigating stress concentrators, manufacturers can enhance the ductility and strain capacity of 3D printed parts. For instance, the compressive strength of ECC was greater than 115 MPa, with a tensile strength and strain of 12 MPa and 9%, respectively.
A 3D printed ECC with 7 MPa tensile strength and 4% strain capacity using 12 mm PE fibers was accomplished via nozzle standoff distance adjustments.
Testing Your Part’s Ductility
Testing the ductility of 3D printed parts is crucial to determine their ability to deform without breaking, which is essential for applications that require flexibility and resistance to deformation. Ductility, a property of materials, specifically refers to a material’s ability to deform without fracture and to be stretched or drawn out without failure.
For example, materials such as TPU 70-A combine their rubber-like properties with high elongation at break and consequently are the go-to for any applications requiring high ductility. Knowing why you should test your 3D printed parts for ductility is crucial.
To test a part’s ductility, you usually apply tensile stress. This aids engineers in understanding the material’s performance under various loads and tweaking their designs as necessary. For instance, material ductility can be affected by its microstructure, with some materials benefiting from a heterogeneous structure.
Here are some methods for testing ductility:
-
Tensile testing: This involves subjecting the material to tensile stress until it deforms or breaks, providing valuable insights into the material’s ability to withstand plastic deformation.
-
Impact testing: This method involves subjecting the material to sudden impacts to determine its ability to absorb energy without breaking.
-
Bend testing: This test involves bending the material to determine its ability to deform without breaking.
-
Compression testing: This method involves subjecting the material to compressive stress to determine its ability to withstand deformation.
Testing is instrumental in measuring and refining ductility. By testing 3D printed parts, engineers can figure out their ductility and optimize their designs accordingly. For example, the introduction of reinforcements, like TiB nanowires, can enhance the tensile ductility of some materials.
Companies like Wefab AI offer contract manufacturing services that include design for manufacturability, quality control, and logistics, which can help optimize the ductility of 3D printed parts.
Iterative testing and design for ductility optimization is an important process in making sure 3D printed parts are up to snuff. This includes designing and testing several versions of a part, each time making modifications based on your test results.
With AI-driven solutions, businesses can fine-tune their concepts and minimize the iterations needed to attain the specified ductility. For instance, Wefab AI’s AI-first method allows for automated checks for manufacturability and material optimization — potentially reducing lead times and increasing quality.
Are Your 3D Printed Parts Failing Under Real-World Stress?
Our manufacturing experts can help you design for ductility, advising on material selection, part orientation, and geometric features to prevent stress concentrations and create truly resilient components.
Get a Free Design Review to Enhance Your Part's Durability.
Conclusion
Manufacturers in industries such as climate tech, robotics, electric vehicles (EVs), and consumer hardware face significant challenges in balancing strength and ductility in 3D-printed parts, often grappling with material limitations, inconsistent performance, and costly iterations that delay production. Understanding and optimizing ductility—the ability of a material to deform without fracturing—enables designers to create more robust, reliable components tailored to demanding applications. By leveraging advanced material selection, precise printing parameters, and iterative design strategies, manufacturers can enhance part durability, reduce failure rates, and accelerate time-to-market.
Wefab.ai’s AI-driven platform empowers teams by providing real-time insights into material properties, design optimization, and process controls, achieving up to 30% faster production cycles and reduced material waste. Ready to elevate the performance of your 3D-printed parts? Explore Wefab.ai’s advanced additive manufacturing solutions and request an instant quote to drive precision, durability, and efficiency in your projects.
Frequently Asked Questions
What is ductility in the context of 3D printing
Ductility, a crucial property of flexible 3D printing materials, refers to a material’s ability to deform plastically without fracturing, ensuring that 3D-printed parts can withstand mechanical stress in robotics and EV applications.
How does ductility impact the performance of 3D-printed parts?
Higher ductility in flexible materials enhances a part’s resistance to cracking and deformation under stress, significantly increasing durability and lifespan, which is vital for functional parts in climate tech and consumer hardware subjected to dynamic loads.
What factors influence ductility in 3D-printed parts?
Material type, print orientation, and infill density significantly affect the tensile properties of flexible 3D printing materials. Optimizing these factors ensures robust parts, with Wefab.ai’s AI tools providing precise parameter recommendations for additive manufacturing.
Is high strength always preferable to high ductility in 3D printing?
High strength in alloys may compromise ductility, leading to brittle parts unsuitable for certain applications. Balancing both properties, guided by project needs, ensures optimal performance, especially for flexible materials in EV and robotics components.
How can manufacturers improve ductility in 3D-printed parts?
Ductility can be enhanced through careful material selection, including flexible 3D printing materials, optimized print settings, and iterative design testing. Wefab.ai’s platform offers real-time DFM feedback to improve ductility and reduce defects by up to 25%.
How does Wefab.ai support ductility optimization in 3D printing?
Wefab.ai’s AI-driven platform analyzes flexible 3D printing materials and print parameters to maximize ductility, ensuring high-quality metal parts for climate tech and consumer hardware while reducing production time by up to 30% through precise process optimization.
How does Wefab.ai enhance cost efficiency for ductile 3D-printed parts?
Wefab.ai minimizes material waste and iteration costs through AI-guided material selection and process controls, cutting expenses by up to 28%. Its integrated platform ensures cost-effective, high-ductility flexible materials for robotics and EV projects.
