Enhance Your 3D Printed Elements with Open-Supply 3D Printer Analysis

Experimental Willpower of the Results of Slicer Settings on the Mechanical Energy of Fused Filament Fabrication Manufactured Specimens

Samuel Hart and Trevor Grey

Mechanical Engineering
Valparaiso College
Valparaiso, Indiana

Dr. Daniel Blood

Assistant Professor of Mechanical Engineering and Bioengineering
Valparaiso College
Valparaiso, Indiana

ABSTRACT:

The buyer-level Fused Filament Fabrication (FFF) group has little scientific data obtainable on the mechanical properties of printed elements. Even much less is understood concerning the relationship between slicer settings, equivalent to hotend temperature, and the ensuing mechanical energy with numerous filaments. This paper presents a proposed methodology of characterizing the connection between slicer settings for various filament sorts and the ensuing mechanical energy of FFF elements. Moreover, outcomes of testing MatterHackers’ MH Construct PLA, PRO Collection PLA, PRO Collection ABS, PRO Collection PETG, PRO Collection Nylon, and NylonX filaments are reported. It’s discovered that NylonX has the best energy to weight ratio at 92 lbf/g, MH Construct PLA has the best peak load at 478 lbf, and PRO Collection Nylon has the best ductility of the filaments examined with 25.6% pressure at failure. PRO Collection PLA energy depends the least on the path of the utilized pressure with an isotropic score of fifty%. Extra parameters, equivalent to half fan velocity, print velocity, and infill share, are examined to find out their impact on tensile energy.

1. INTRODUCTION

1.1 Motivation

The expiration of Stratasys’ Fused Deposition Modeling (FDM) patent in 2009 resulted in a beforehand unimaginable explosion in do-it-yourself (DIY) tech [1]. The open-source group renamed the printing course of Fused Filament Fabrication (FFF) to forestall infringement on Stratasys’ FDM trademark. Filament based mostly 3D printing maintains its place as the first printer expertise for shoppers because of the relative low price of entry, and the worldwide help group. The aggressive FFF printer market adjustments at a staggering tempo from 12 months to 12 months, and new capabilities are allowed by this new tech. Improvements in printer {hardware} and new kinds of filament present customers with an ever-expanding array of choices. Whereas many of those improvements are designed to make printers extra user-friendly, many extra declare to supply the ‘finest’ prints doable; nonetheless, with no scientific comparability of the options it is not possible to validate these claims. The analysis crew at Valparaiso College (Valpo) acknowledges that there’s a want for unbiased analysis of printer parts and consumables, and the crew has spent two years creating a repeatable methodology of analysis.

[1] Crump, S. Scott, “Equipment and Methodology for Creating Three-Dimensional Objects,” U.S. Patent 5 121 329, 9 June 9, 1992.

1.2 Figuring out Elements that Have an effect on Printed Elements

A aim for many 3D printing fans is to supply elements which might be aesthetically pleasing, and have comparatively excessive mechanical energy. Sadly, these two desired traits might not be doable with the identical printer/filament/slicer setting combos, and solely the person printing the half can decide if they need perform, type, or a mixture. A further problem with quantifying aesthetics is the subjective nature of attractiveness. Determine 1 exhibits an instance of two prints that come from the identical mannequin and total settings, however with a distinction within the .STL decision leading to ‘easy’ and ‘low-poly’ prints. As a result of subjective nature of aesthetics, the Valparaiso College analysis crew is specializing in quantifying mechanical properties.

Step one in evaluating energy is figuring out failure modes of printed elements. Preliminary tensile testing of FFF specimens reveals three main modes of failure: yielding of the fabric, delamination between Z-layers, and delamination within the X-Y path. Subsequent, course of parameters are recognized that will contribute to failure for every of the three modes. The next conclusions are based mostly on evaluation of the failed specimens, overview of slicer settings, and comparability of printer parts.

1.2.1 Failure Attributable to Yielding

Yield energy is outlined because the transition from elastic (recoverable) deformation to plastic (everlasting) deformation [2]. Within the case of an injection molded half, that is largely because of the materials properties of the polymer, and the inner residual stresses because of the injection course of. FFF printing is just like injection molding on this respect, however adjustments in materials properties and the bodily means of producing inner residual stresses are distinctive. Extruded materials properties are principally a perform of the polymer kind, however the materials properties are additionally affected by the extent of polymer degradation. This degradation of the polymers can happen from moisture, ultra-violet (UV) gentle, chemical compounds, and most notable for FFF printing, heating. Some degradation possible happens earlier than the consumer receives the filament because of the potential use of recycled plastics, and heating of the polymer on the time of filament manufacturing. Additional degradation can happen on the consumer’s finish from improper filament storage, or overheating throughout extrusion. Consequently, the three gadgets recognized as necessary for materials properties are filament kind (materials, producer, and storage historical past), extruder-hotend-nozzle mixture, and slicer settings (hotend temperature and extrusion fee).

Inner residual stresses are attributable to the uneven cooling of a cloth. Injection molded elements sometimes cool faster on the surface surfaces as in comparison with the within. The polymer turns into extra inflexible and contracts because it cools; consequently, if the surface floor cools too quickly the inner materials can have no solution to freely contract. Determine 2 exhibits an instance of this phenomenon with a visual dip within the injection molded half floor. This leads to a non-zero state of stress within the half earlier than any exterior masses are utilized, and finally will have an effect on the yield energy. FFF printed elements expertise the same inconsistency in cooling, however it’s attributable to the delay between extrusion of the layers. New layers are extruded at a better temperature than the cooled earlier layer, and when the brand new layer cools it’ll trigger a contraction of each layers. Determine 3 demonstrates warping of printed elements that generally happens with no heated mattress or managed environmental situations. Printing on a heated mattress or controlling ambient temperatures permits every layer to chill to a better ambient temperature, and thus leads to a extra constant cooling of layers and decreased warping. The first gadgets recognized as necessary for inner residual stresses are filament kind (materials), printer ambient situations (heated mattress and heated chamber), and slicer settings (hotend temperature and extrusion velocity).

[2] Beer, Ferdinand P., et al., Mechanics of Supplies, McGraw-Hill Training (India) Non-public Restricted, 2017.

1.2.2 Failure Attributable to Delamination within the Z-Route

Delamination of Z-layers, as seen in Determine 4, happens when there’s inadequate bonding between printed layers. This can be a results of incorrect extrusion temperature leading to a chilly joint, extreme contraction between layers, or from international contaminants stopping correct physiochemical adhesion. The recognized causes of delamination are primarily because of the filament (materials, producer, and storage historical past), extruder-hotend-nozzle mixture, printer heating functionality (mattress and chamber), and slicer settings (hotend temperature).

1.2.3 Failure Attributable to Delamination within the X-Y Route

Geometric accuracy of injection molded elements is closely influenced by the standard of the mould and the cooling of the elements after injection, however FFF print accuracy relies on the flexibility to exactly management the place and quantity of filament extruded. The right amount of the fabric have to be extruded within the appropriate location for every layer. The fabric is extruded in strains that could be parallel or overlap different extruded strains. The standard of the line-to-line bond is necessary to forestall extruded strains from separating underneath load. Slicing software program sometimes modifies the extruder path to create overlap between outlines and infill to advertise adhesion, but when the extrusion settings are incorrect there could also be inadequate materials extruded to permit correct bonding between the respective extruded strains. The recognized variables affecting delamination within the X-Y path are filament (materials, producer, and storage historical past), extruder-hotend-nozzle mixture, printer movement system accuracy/repeatability, and slicer settings (hotend temperature, define overlap, and extrusion multiplier).

1.3 Testing Parameters for Part One

Desk 1: Failure modes and recognized causes of failure.

Desk 1 exhibits a abstract of the earlier part evaluation. The seemingly limitless mixture of the above elements makes it impractical to check each doable variable directly. The Valpo crew acknowledges that many shoppers are financially restricted on {hardware} modifications, and the buyer group will profit extra from a information on free software-based adjustments to their printing course of. The crew additionally recognized the significance of performing early exams with generally utilized parts in order that outcomes usually tend to apply to a typical consumer’s setup.

1.4 Testing ‘Dumbbell’ Specimens

The primary specimen geometry examined is the ASTM D412-06a ‘dumbbell’, as seen in Determine 5. This testing customary evaluates tensile properties of each thermoplastic elastomers and vulcanized thermoset rubbers. This customary was initially chosen to permit testing of inflexible filaments like PLA, and versatile filaments like TPU/TPE.

Preliminary exams with the ‘dumbbell’ specimen reveal that the geometry could also be efficient for testing polymer/elastomer sheets, however it’s not conducive for FFF printed half testing. The geometry’s faults are as follows:

1. The specimen have to be clamped on each ends for tensile exams, and this restricts the consumer to 100% infill of the ends to forestall crushing.
2. Any misalignment of the specimen within the testing equipment leads to non-uniaxial forces that contribute to inconsistent peak specimen masses.
3. Printing the specimens in a vertical orientation leads to a comparatively tall and slender print that’s vulnerable to geometric printing errors on the prime.
4. The vertical association additionally leads to stacked potential failure factors, and the weakest layer bond controls the breaking energy.
5. The size of the specimen limits variation within the p.c infill, variety of outlines, and variety of prime/backside layers.
6. The space between the highest floor of the printed half and the printer mattress is a number of orders of magnitude totally different for vertical and horizontally printed specimens. The distinction partly heating can have an effect on the bond energy, and this could end in non-equivalent comparability of the 2 print orientations.
7. Few horizontally oriented specimens could be printed at one time so it reduces batch specimen print dimension.

These shortcomings reveal the necessity for a brand new specimen geometry to correctly characterize the FFF course of.

2. EXPERIMENTAL SETUP

2.1 Tensile Specimen Geometry

The inherent variability of FFF 3D printers made it difficult to pick the specimen geometry that leads to essentially the most constant tensile testing. The aim is to search out essentially the most acceptable specimen geometry the place the outcomes could be extrapolated to a number of hotend and printer combos. Desired properties of the brand new specimen are:

1. The flexibility to print the specimen in several orientations with out frequent printer limitations affecting the specimen energy.
2. A geometry that enables for a large number of slicer settings to vary the ensuing printed specimen.
3. Comparatively low specimen quantity to reduce print time and price.
4. Comparatively small footprint to allow giant batch sizes.
5. Ease of elimination from printer mattress to reduce the impact of specimen dealing with.
6. Skill to reduce non-uniaxial forces produced from misalignment within the tensile testing equipment.

The brand new specimen design, as proven in Determine 6 and seven, overcomes the challenges found within the first set of exams in a number of methods. First, the brand new specimen geometry self-aligns when performing tensile testing as a consequence of using loading pins as a substitute of clamps. This additionally eliminates the necessity for clamping onto stable sections of the specimen. The brand new loading course of introduces a better degree of repeatability and reduces the cycle time for exams. The specimen form can also be designed with slicer settings in thoughts; particularly, prime/backside layers, variety of outlines, and p.c infill. The thicker specimen permits for a wider vary of those settings to be examined on the identical geometry. The print space decreases from 2500 mm2 to 1100 mm2, and the stable physique quantity stays comparatively low at 7000 mm3. Lastly, the form permits for the elements to be printed in numerous configurations with out requiring important helps, or rising the size to thickness ratio excessively.

2.2 Printing {Hardware} and Filament

The Prusa i3 MK2 printer is used because the testing {hardware} because of the sub $1000 price ticket, a direct-drive extruder, a heated mattress, real E3D-V6 hotend, and auto-leveling {hardware}. Additionally, there is no such thing as a enclosure to guard the specimen or printer from the house setting. This permits for extra generalization as most finances client printers should not have enclosures. Sooner or later, an enclosure will probably be added so the advantages of environmental safety from disturbances, equivalent to drafts from an AC vent, could be quantified. The printers have been assembled by one particular person on the crew. The one modification made to the printers is exchanging the brass nozzle for a hardened metal nozzle of the identical diameter when printing NylonX. That is performed to forestall put on in order that the brass nozzles can be utilized for future specimens.

MatterHackers’ filament is used for the testing as a consequence of its widespread use, availability of filament sorts, and their filament particular options for baseline slicer settings. Within the title of transparency it also needs to be famous that MatterHackers donated filament to help this analysis, however all outcomes are absolutely generated by the Valparaiso College crew with out modification.

2.3 Batch Printing Configuration

Ten specimens are printed in every batch to restrict print time whereas sustaining smaller printer compatibility. Extra batches are printed after the ‘finest’ extrusion temperature is decided to scale back uncertainty. A complete of thirty specimens are produced for the ‘finest’, ‘finest’+5 ˚C, and ‘finest’-5 ˚C extrusion temperatures respectively. Format of the specimens, as seen in Determine 8, is dictated robotically by Simplify3D. This eliminates the prospect of inconsistent spacing when creating new print recordsdata. Specimens and unused filament are saved inside a Ziploc WeatherShield 26.5 Quart Storage container with a 1.7 lbm silica gel desiccant bead canister till testing or printing. Tensile testing is usually accomplished inside 3 days of printing the specimens.

2.4 Slicer Software program

Simplify3D is used because the slicer software program as a consequence of its versatility with setting selections and its recognition amongst shoppers. All baseline parameters are pulled from the MatterHackers on-line information. If a variety is given then the imply worth is used. Testing focuses closely on figuring out the ‘finest’ hotend temperatures for every respective filament. That is outlined because the minimal temperature the place the tensile energy stays comparatively fixed no matter a rise within the extrusion temperature. The bottom worth is reported to reduce oozing/zits frequent with larger extrusion temperatures. Essentially the most acceptable hotend temperature is a hotly debated matter throughout the printing group; nonetheless, numerous variables can have an effect on the ‘finest’ temperature for every filament kind. The hotend temperature is the one parameter different within the first set of exams. Extra exams are carried out after the ‘finest’ hotend temperature is decided. These exams concurrently fluctuate totally different parameters to find out tensile energy sensitivity.

All of the prints are carried out utilizing an SD card for g-code switch. Inconsistent switch of the g-code to the printer from a pc can come up as a consequence of connection or software program points, and using a SD card eliminates that further variability.

3. TESTING METHODOLOGY

3.1 Verification of Equal Printer Assumption

Two Prusa i3 MK2s are used on this part to expedite testing. It’s essential to validate the null speculation that any distinction within the tensile energy between the 2 printers is because of the inherent variability within the course of. These exams used a single roll of black MH Construct Collection PLA printed at 200 °C and 215 °C respectively. Outcomes for these take a look at are proven in Desk 2. A two-way evaluation of variance is performed on the tensile energy of the specimens after tensile testing. The impact of utilizing two separate printers will not be statistically important on the 0.05 significance degree (F ratio = 0.024, p>0.05). The statistically insignificant distinction justifies the transfer to deal with variability launched by the 2 printers as negligible

Desk 2: Tensile take a look at outcomes to find out whether it is acceptable to contemplate the printers as equal.

A collection of the baseline slicer settings for the printed specimens are listed in Desk 3, and detailed screenshots of settings are supplied within the appendix. Non-filament particular settings, equivalent to print velocity, are generated from the Prusa i3 MK2 profile on Prusa’s official web site. Any remaining settings are chosen from previous expertise and information from the Valpo crew.

Desk 3: A collection of the slicer baseline slicer settings used within the first set of exams.

3.3 Willpower of Minimal Hotend Temperature

Minimal hotend temperature for every kind of filament is decided from evaluation of each the height load and energy to weight ratios. Most temperature exams begin at 15 °C beneath the MatterHackers common advisable hotend temperature; nonetheless, in some instances after information is reviewed, it could be decided that the minimal hotend temperature will not be reached. In these instances, hotend temperature is dropped by 5 °C for each batch till both the minimal temperature is discovered, or print failure happens (e.g. delamination within the z-direction throughout printing).

3.4 Tensile Testing Process

After a batch of specimens finishes printing, it’s positioned in a Ziploc WeatherShield 26.5 Quart Storage container with a 1.7 lbm silica gel desiccant bead canister inside for at the least 8 hours. Specimens are examined at room temperature, 70 ± 5 °F. When sufficient specimens are printed, every batch is then weighed with an AWS-100 scale, and the common recorded. Specimens are loaded right into a MTS QTest 150 tensile machine through the loading pins which begin with a center-to-center distance of roughly 19 mm. A relentless elongation fee of 5 mm/min is utilized when testing begins. This testing velocity relies off the ASTM customary mentioned beforehand. A 33700 lbf (150 kN) MTS load cell is used to measure the utilized load, the displacement relies on the body readings, and the info is collected by a Dell Optiplex 990 PC at 60 Hz.

4. RESULTS

4.1 Hotend Tensile Outcomes

Desk 4: Tensile take a look at outcomes for MatterHackers filament. Values signify the common for specimens printed at or above the minimal advisable hotend temperature.

A comparability of the experimentally decided tensile properties for every respective filament kind is offered in Desk 4. The desk compares prints of MatterHackers MH Construct PLA, PRO Collection PLA, PRO Collection PETG, PRO Collection ABS, PRO Collection Nylon, and NylonX. The height load, energy to weight ratio, and pressure at failure are all averages of specimens that meet or exceed the minimal instructed hotend temperature. The items of lbf/g are chosen for the energy to weight ratio as a consequence of customers’ familiarity with lbf and the frequent follow of measuring filament/prints in grams.

These numbers are usually not meant to foretell the energy of a consumer’s particular printed half. The outcomes are merely used to find out the relative energy of 1 filament to a different. This permits a wider viewers to use the teachings discovered in direction of their very own prints. The advanced nature of FFF printed elements requires a extra advanced evaluation of stress concentrators, loading path/kind/fee, and the results of working temperature/humidity/age/and so on… to find out the mechanical properties of a particular half.

4.1.1 Black MH Construct PLA

MatterHackers Black MH Construct PLA is the primary filament examined. Determine 9 exhibits the hotend-temperature energy to weight ratio (S-W) curve for Black MH Construct PLA. The plot exhibits that a rise from 185 °C to 200 °C yields a 43% enhance within the energy to weight ratio. The graph exhibits that after 200 °C the height load stays comparatively fixed; consequently, the advisable minimal hotend temperature for Black MH Construct PLA is 200 °C.

4.1.2 Black PRO Collection PLA

Determine 10 exhibits the outcomes for MatterHackers Black PRO Collection PLA. It’s anticipated that PRO Collection PLA will carry out just like the MH Construct PLA, and above the 200 °C mark the 2 supplies produce related outcomes; nonetheless, PRO Collection PLA didn’t expertise the drop off in energy beneath 200 °C. The authors suggest printing with at the least 200 °C for this explicit printer setup because of the slight enhance within the S-W ratio; nonetheless, it doesn’t seem that there will probably be a major discount within the half energy for this testing orientation beneath 200 °C.

4.1.3 Black PRO Collection ABS

Black PRO Collection ABS filament produced the weakest prints with most failing beneath 400 lbf. Determine 11 exhibits the inconsistent S-W ratio pattern for the examined hotend temperatures. One situation with printing the ABS specimens is that warping of the specimens happens for many batches. It’s doable that the specimens carry out poorly throughout tensile testing as a consequence of residual stresses induced by the uneven cooling, and a rise within the ambient temperature may cut back this impact. Extra exams past the preliminary ten specimens are usually not carried out because of the challenges in printing ABS with the present setup. The Valpo crew is hesitant to make a suggestion with out further exams in an elevated temperature printing setting, however the specimens printed at 220 °C demonstrated the best peak load and best ductility; subsequently, that’s the present instructed minimal hotend temperature.

Future exams on all filament sorts will reveal what enhancements within the tensile energy are available with an elevated ambient temperature.

4.1.4 Crimson PRO Collection PETG

Crimson PRO Collection PETG outcomes, as proven in Determine 12, reveal a rise within the S-W ratio from 235 °C to 240 °C, after which a comparatively fixed S-W ratio above 240 °C. This leads the Valpo crew to counsel a minimal hotend temperature of 240 °C. It is very important be aware that though PRO Collection PETG has a decrease S-W ratio as in comparison with PLA, it didn’t fail in a brittle method. PRO Collection PETG specimens sometimes stayed intact, and had roughly double the elongation earlier than failure as in comparison with PLA. This enhance within the elongation result in an roughly threefold enhance within the toughness because of the form of the stress-strain curve. The upper extrusion temperature and slight variability of samples leads the Valpo crew to hypothesize that further beneficial properties in energy could also be discovered with a rise within the ambient print temperature.

4.1.5 Blue PRO Collection Nylon

Nylon is broadly thought-about as a comparatively ductile polymer. MatterHackers Blue PRO Collection Nylon carried out as anticipated with the best ductility score of all filaments by greater than 100%. PRO Collection Nylon’s most fascinating attribute is its failure modes. At decrease hotend temperatures PRO Collection Nylon’s layers delaminate inflicting peak load functionality to drop. The delamination impact disappears after a hotend temperature threshold of 245 °C is obtained, and the failure mode transitions right into a extra anticipated yielding failure. Each PRO Collection PETG and NylonX expertise the delamination failure, however the Nylon filament requires a better hotend temperature earlier than the failure mode dies out. Determine 13 exhibits that the S-W ratio dips at 250 °C and the Valpo crew believes this is because of a single 10 specimen batch that exhibited decrease S-W ratios as in comparison with the opposite batches at 250 °C. The instructed minimal hotend temperature for PRO Collection Nylon on this explicit setup is 245 °C.

4.1.6 NylonX

Maybe essentially the most fascinating filament take a look at outcomes are MatterHackers’ NylonX. There may be important issue bonding the z-layers of NylonX at low hotend temperatures. The crew attributes this to an open print mattress setting fairly than an enclosed chamber. The S-W ratio of NylonX is the bottom of all filaments examined on the low temperature finish, nevertheless it achieves the best score after the 260 °C mark. Using a hardened metal nozzle of 0.4 mm allowed the crew to protect the brass nozzles for testing continuity, however the decrease thermal conductivity of the metal limits warmth switch to the filament. To rectify this, the crew printed at larger hotend temperatures than different filaments. Determine 14 exhibits that rising the hotend temperature from 255 °C to 260 °C leads to a 55% enhance within the S-W ratio. The instructed hotend temperature for NylonX with a hardened metal nozzle is at the least 260 °C.

4.2 Extra Checks

Figuring out minimal hotend temperatures is a vital side of FFF printing, nevertheless it doesn’t embody the entire elements that have an effect on print energy. The Valparaiso College crew realizes that the tensile energy of elements printed within the earlier part are depending on further elements equivalent to half fan cooling, z-layer peak, variety of outlines, variety of prime/backside layers, infill share, and print velocity. An in-depth evaluation of all these elements would require a paper of its personal, however these preliminary outcomes ought to help customers in making extra knowledgeable selections about their slicer settings.

4.2.1 Half Fan Cooling

Desk 5: Tensile outcomes for half fan exams with Black MH Construct PLA.

The usage of a component fan can enhance the capabilities of a printer throughout bridging operations or for areas with steep angles, nevertheless it additionally might have an effect on the flexibility for layers to bond. Testing this impact on the tensile energy first requires figuring out the minimal hotend temperature, after which printing a batch of thirty specimens in Black MH Construct PLA with the half fan off. Desk 5 exhibits that printing with the half fan off produces a statistically important impact on the height load; nonetheless, the rise in energy is simply 5%. The fan’s low affect on half energy signifies that the fan can be utilized with a statistically important, however minimal impact on the energy of PLA elements.

4.2.2 Layer Peak

Decreasing the layer thickness can have a constructive impact on the beauty look of a printed half, however it might additionally enhance the general print time. These are comparatively straightforward outcomes to foretell with trendy slicer outputs, however the impact on mechanical energy with totally different layer thicknesses is unknown.

Specimens from part 4 are printed with 0.3 mm layer heights to lower the general print time. Extra exams are run with 0.1 mm layers to find out if the thinner layers have a statistically important impact on the tensile energy. One further modification to the baseline g-code is to regulate the variety of prime and backside stable layers. That is an try to keep up the general thickness of the stable layers on the highest and backside of every tensile specimen.

Desk 6 exhibits the outcomes of the layer peak take a look at, and the 0.3 mm and 0.1 mm tensile outcomes are statistically related. Extra exams are mandatory to enhance the statistical certainty that layer peak doesn’t have an effect on the tensile energy of specimens, however these preliminary exams counsel that it doesn’t play a major function.

Desk 6: Tensile outcomes for layer peak exams with Black MH Construct PLA.

4.2.3 Outlines or Prime/Backside Layers

Including materials to printed elements can enhance the general energy. The consumer can add outlines, prime/backside stable layers, or enhance infill share, however which methodology of addition is best in rising energy? The Valpo crew printed specimens with double the variety of outlines, double the stable layers on the highest/backside, and a rise to 70% infill. The worth of 70% infill is chosen because of the related specimen weight in comparison with the opposite two modified specimens.

Evaluation of the leads to Desk 7 demonstrates that a rise within the energy to weight ratio is feasible with outlines and stable layers, however that rising the infill share didn’t have a statistically important impact. It is very important be aware that the kind of loading and print geometry is essential to the place materials must be added. Compressive masses or advanced geometry might shift the necessary areas. Future exams with totally different loading configurations might shine gentle on these results.

Desk 7: Tensile energy of specimens with added materials in several areas.

4.2.4 Infill

The earlier part critiques the impact of a rise from 50% infill to 70% infill. Extra infill percentages should be investigated to find out if the rise in energy follows a pattern.

Determine 15 shows p.c infill versus peak load for specimens present process tensile loading. This graph exhibits that from 50% to 80% infill the slope for rising energy is comparatively shallow; nonetheless, the slope is roughly 4 instances higher above 80% infill. That is possible as a consequence of elevated bonding between infill strains. These outcomes will should be repeated for different geometries and masses, equivalent to pure compression, to definitively state a higher enhance within the peak load is noticed for the 80-100% infill vary.

4.2.5 Print Pace

Print velocity is one other issue that sometimes has an impact on the consumer expertise. The flexibility to print ever quicker is a requirement on the FFF business, however the impact of this enhance in print velocity on half energy is typically neglected.

The Prusa i3 MK2 baseline specimens are all printed at 1800 mm/min with the intent of minimizing geometric errors. The printer is, nonetheless, able to printing quicker. Extra velocity take a look at outcomes are proven in Determine 16. Black MH Construct PLA exhibits no statistically important lower in energy when rising the velocity from 1800 to 3600 mm/min, however at 4800 mm/min the S-W ratio decreases by 8%. Black PRO Collection PLA S-W ratio barely will increase at 3600 mm/min, however just like MH Construct PLA it decreases at 4800 mm/min. Solely the top consumer can decide if this lower in energy is suitable, and if there are further beauty results from printing at these larger speeds. The impact of accelerating print velocity will possible change based mostly on the geometric accuracy of printers at larger speeds, and on the flexibility of the hotend-nozzle mixture to switch ample vitality into the extruded filament.

4.3 Abstract of Check Outcomes

Desk 8: Comparability of MatterHackers filaments.

Desk 8 exhibits the relative rankings of peak load, energy to weight ratio, ductility, and isotropic (non-directionality of energy). Analyzing the desk exhibits that MH Construct PLA and PRO Collection PLA are wonderful normal use filaments for the common consumer. They’ve excessive peak masses, and exhibit the very best isotropic score. The primary downside is the comparatively brittle failure as in comparison with PRO Collection PETG and PRO Collection Nylon.

PRO Collection ABS carried out poorly within the tensile exams with the bottom peak load, S-W ratio, and comparatively low ductility. These outcomes, coupled with the problem of warping specimens, make it exhausting to suggest ABS for this printer setup. The emission of styrene whereas printing ABS additional reduces the attractiveness of this filament kind [3]. The Valpo crew believes that the arrival of newer filament sorts eliminates the necessity for ABS within the client printing market.

PRO Collection PETG outcomes characterize the fabric as a well-rounded filament. The filament is barely weaker than PLA, however with a ~100% enhance within the pressure at failure. It has the second highest ductility score and the second highest isotropic score. There are nonetheless challenges related to printing in PETG, equivalent to the upper extrusion temperature, however total PETG has the potential to problem PLA as the first filament kind.

PRO Collection Nylon and NylonX are difficult filaments to print; nonetheless, additionally they include some distinctive advantages. If there’s a want for prints to exhibit excessive deformation with out failure, Nylon is the instructed filament. NylonX alternatively is extra appropriate for weight-dependent purposes, like customized drone elements.

[3] P. Azimi, D. Zhao, C. Pouzet, et al., “Emissions of Ultrafine Particles and Risky Natural Compounds from Commercially Out there Desktop Three-Dimensional Printers with A number of Filaments,” Environmental Science and Know-how, Vol. 50, pp 1260-1268, Jan. 2016.

5. CONCLUSION

The analysis crew at Valparaiso College is working to tell the buyer FFF group on how slicer settings, notably hotend temperature, have an effect on tensile properties of various filament supplies. The outcomes can dispel many conventional myths relating to client FFF printing, and they’ll hopefully help each skilled and novice 3D printer customers in figuring out essentially the most relevant filament for his or her mission. FFF printers have many variables that have an effect on half energy outdoors of simply the slicer settings; subsequently, it’s not advisable to make use of this information to estimate the energy of printed elements. As an alternative, the analysis crew suggests you have a look at the relative values to find out how totally different filament sorts will possible carry out by yourself printer. Essentially the most acceptable slicer settings for different hotend fashions, filament diameters, nozzle diameters, and so on.… might fluctuate broadly. The Valpo crew hopes the outcomes offered on this report encourage customers to contemplate how all these variables may have an effect on printed elements, and the crew hopes future experiments will solely enhance parameter consciousness.

The Valpo crew is all the time on the lookout for methods to help the buyer FFF group. You may vote on the subsequent space of analysis by visiting our social media accounts on the subsequent web page!

ABOUT THE ACCELERATED 3D PRINTING LAB AND VALPARAISO UNIVERSITY

The Accelerated 3D Printing Lab is situated within the School of Engineering at Valparaiso College. Engineering at Valpo is an undergraduate solely program that’s persistently ranked within the prime 20 undergraduate engineering applications within the nation by U.S. Information & World Report. The Accelerated 3D Printing Lab was established within the Summer time of 2018 to help Valpo’s additive manufacturing analysis. College students examine quite a lot of conventional and novel additive manufacturing strategies with the intent of open entry to the analysis.

ABOUT THE AUTHORS

Samuel Hart ’17 and Trevor Grey ’20 examined over 2000 specimens to find how slicer settings have an effect on the tensile energy of elements. The outcomes on this paper wouldn’t be doable with out their exhausting work and dedication. Dr. Daniel Blood, Assistant Professor of Mechanical Engineering and Bioengineering at Valpo, oversaw the work carried out by Sam and Trevor.

Extra because of Kelsey Unser, Rima Miller, Tyler Smar, and William Foy for his or her assist in establishing the analysis.

Valparaiso College School of Engineering Web site

Accelerated 3D Printing Lab Fb: @Accelerated3DPrintingLab

Twitter: @printing_lab

SPECIAL THANKS TO DAVE GAYLORD AT MATTERHACKERS

The Valpo crew appreciates MatterHackers’ donation of filament for these exams, and in addition for Dave’s invaluable enter on testing. All filaments examined on this report can be found at their on-line retailer.

Store 3D Printing:

www.matterhackers.com

MatterHackers Fb:

@MatterHackers

Twitter:

@MatterHackers

APPENDIX – SIMPLIFY3D SETTINGS