Experimental Willpower of the Results of Slicer Settings on the Mechanical Power 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 patron-level Fused Filament Fabrication (FFF) group has little scientific info out there on the mechanical properties of printed components. Even much less is understood in regards to the relationship between slicer settings, akin to hotend temperature, and the ensuing mechanical power with varied filaments. This paper presents a proposed technique of characterizing the connection between slicer settings for various filament sorts and the ensuing mechanical power of FFF components. 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 power 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 power depends the least on the course of the utilized pressure with an isotropic ranking of fifty%. Further parameters, akin to half fan pace, print pace, and infill proportion, are examined to find out their impact on tensile power.
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 stop infringement on Stratasys’ FDM trademark. Filament primarily based 3D printing maintains its place as the first printer expertise for customers as a result of relative low value of entry, and the worldwide help group. The aggressive FFF printer market modifications 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 sorts 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 provide the ‘finest’ prints potential; nonetheless, with out a scientific comparability of the alternate options it is inconceivable to validate these claims. The analysis workforce at Valparaiso College (Valpo) acknowledges that there’s a want for unbiased analysis of printer parts and consumables, and the workforce has spent two years growing a repeatable technique 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 Components that Have an effect on Printed Elements
A purpose for many 3D printing fans is to provide components which might be aesthetically pleasing, and have comparatively excessive mechanical power. Sadly, these two desired traits might not be potential with the identical printer/filament/slicer setting combos, and solely the person printing the half can decide if they need perform, kind, or a combination. A further problem with quantifying aesthetics is the subjective nature of attractiveness. Determine 1 reveals 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. Because of the subjective nature of aesthetics, the Valparaiso College analysis workforce is specializing in quantifying mechanical properties.
Determine 1. Examples of snowman prints in excessive decision (left) and low-poly (proper).
Step one in evaluating power is figuring out failure modes of printed components. Preliminary tensile testing of FFF specimens reveals three major modes of failure: yielding of the fabric, delamination between Z-layers, and delamination within the X-Y course. Subsequent, course of parameters are recognized which will contribute to failure for every of the three modes. The next conclusions are primarily based on evaluation of the failed specimens, evaluate of slicer settings, and comparability of printer parts.
1.2.1 Failure Resulting from Yielding
Yield power 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 as a result of materials properties of the polymer, and the interior residual stresses because of the injection course of. FFF printing is much like injection molding on this respect, however modifications in materials properties and the bodily strategy of producing inside residual stresses are distinctive. Extruded materials properties are largely a perform of the polymer sort, 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) mild, chemical substances, and most notable for FFF printing, heating. Some degradation doubtless happens earlier than the person receives the filament as a result of potential use of recycled plastics, and heating of the polymer on the time of filament manufacturing. Additional degradation can happen on the person’s finish from improper filament storage, or overheating throughout extrusion. Consequently, the three gadgets recognized as essential for materials properties are filament sort (materials, producer, and storage historical past), extruder-hotend-nozzle mixture, and slicer settings (hotend temperature and extrusion fee).
Inside residual stresses are attributable to the uneven cooling of a cloth. Injection molded components 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 interior materials could have no strategy to freely contract. Determine 2 reveals 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 hundreds are utilized, and in the end will have an effect on the yield power. FFF printed components expertise an identical inconsistency in cooling, however it’s attributable to the delay between extrusion of the layers. New layers are extruded at the next temperature than the cooled earlier layer, and when the brand new layer cools it can trigger a contraction of each layers. Determine 3 demonstrates warping of printed components that generally happens with out a heated mattress or managed environmental situations. Printing on a heated mattress or controlling ambient temperatures permits every layer to chill to the next ambient temperature, and thus leads to a extra constant cooling of layers and decreased warping. The first gadgets recognized as essential for inside residual stresses are filament sort (materials), printer ambient situations (heated mattress and heated chamber), and slicer settings (hotend temperature and extrusion pace).
[2] Beer, Ferdinand P., et al., Mechanics of Supplies, McGraw-Hill Training (India) Personal Restricted, 2017.
Determine 2. Dip within the floor of a roll of filament attributable to contraction throughout uneven cooling.
Determine 3. Warping of printed half on the construct floor.
1.2.2 Failure Resulting from Delamination within the Z-Path
Delamination of Z-layers, as seen in Determine 4, happens when there may be 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 as a result of filament (materials, producer, and storage historical past), extruder-hotend-nozzle mixture, printer heating functionality (mattress and chamber), and slicer settings (hotend temperature).
Determine 4. Delamination of PLA specimens within the z-direction.
1.2.3 Failure Resulting from Delamination within the X-Y Path
Geometric accuracy of injection molded components is closely influenced by the standard of the mildew and the cooling of the components after injection, however FFF print accuracy relies on the power to exactly management the place and quantity of filament extruded. The correct quantity of the fabric have to be extruded within the appropriate location for every layer. The fabric is extruded in traces that could be parallel or overlap different extruded traces. The standard of the line-to-line bond is essential to stop extruded traces from separating beneath 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 traces. The recognized variables affecting delamination within the X-Y course 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 reveals a abstract of the earlier part evaluation. The seemingly limitless mixture of the above components makes it impractical to check each potential variable directly. The Valpo workforce acknowledges that many customers are financially restricted on {hardware} modifications, and the patron group will profit extra from a information on free software-based modifications to their printing course of. The workforce additionally recognized the significance of performing early assessments with generally utilized parts in order that outcomes usually tend to apply to a typical person’s setup.
1.4 Testing ‘Dumbbell’ Specimens
Determine 5. FFF printed ‘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 assessments 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:
- The specimen have to be clamped on each ends for tensile assessments, and this restricts the person to 100% infill of the ends to stop crushing.
- Any misalignment of the specimen within the testing equipment leads to non-uniaxial forces that contribute to inconsistent peak specimen hundreds.
- Printing the specimens in a vertical orientation leads to a comparatively tall and slender print that’s liable to geometric printing errors on the high.
- The vertical association additionally leads to stacked potential failure factors, and the weakest layer bond controls the breaking power.
- The size of the specimen limits variation within the p.c infill, variety of outlines, and variety of high/backside layers.
- The gap 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 partially heating can have an effect on the bond power, and this is able to lead to non-equivalent comparability of the 2 print orientations.
- Few horizontally oriented specimens will be printed at one time so it reduces batch specimen print dimension.
These shortcomings show 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 out the specimen geometry that leads to probably the most constant tensile testing. The purpose is to seek out probably the most applicable specimen geometry the place the outcomes will be extrapolated to a number of hotend and printer combos. Desired properties of the brand new specimen are:
- The flexibility to print the specimen in several orientations with out widespread printer limitations affecting the specimen power.
- A geometry that enables for a mess of slicer settings to alter the ensuing printed specimen.
- Comparatively low specimen quantity to attenuate print time and price.
- Comparatively small footprint to allow giant batch sizes.
- Ease of removing from printer mattress to attenuate the impact of specimen dealing with.
- Potential to attenuate non-uniaxial forces produced from misalignment within the tensile testing equipment.
Determine 6. Technical drawing of recent specimen.
Determine 7. New specimen design loaded in MTS QTest 150 tensile testing machine. View of the customized loading pins within the MTS machine (left) and post-testing PETG specimen (proper).
The brand new specimen design, as proven in Determine 6 and seven, overcomes the challenges found within the first set of assessments in a number of methods. First, the brand new specimen geometry self-aligns when performing tensile testing attributable to the usage of 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 the next stage of repeatability and reduces the cycle time for assessments. The specimen form can be designed with slicer settings in thoughts; particularly, high/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 components to be printed in various 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} as a result of 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 atmosphere. This permits for extra generalization as most funds shopper printers do not need enclosures. Sooner or later, an enclosure shall be added so the advantages of environmental safety from disturbances, akin to drafts from an AC vent, will be quantified. The printers have been assembled by one particular person on the workforce. 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 achieved to stop put on in order that the brass nozzles can be utilized for future specimens.
MatterHackers’ filament is used for the testing attributable to its widespread use, availability of filament sorts, and their filament particular strategies for baseline slicer settings. Within the identify 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 workforce with out modification.
2.3 Batch Printing Configuration
Ten specimens are printed in every batch to restrict print time whereas sustaining smaller printer compatibility. Further batches are printed after the ‘finest’ extrusion temperature is set 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 routinely by Simplify3D. This eliminates the possibility of inconsistent spacing when creating new print information. 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.
Determine 8: Simplify3D format of ten tensile specimens on a Prusa i3 MK2.
2.4 Slicer Software program
Simplify3D is used because the slicer software program attributable to its versatility with setting decisions and its recognition amongst customers. All baseline parameters are pulled from the MatterHackers on-line information. If a spread 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 power stays comparatively fixed no matter a rise within the extrusion temperature. The bottom worth is reported to attenuate oozing/zits widespread with greater extrusion temperatures. Probably the most applicable hotend temperature is a hotly debated subject throughout the printing group; nonetheless, numerous variables can have an effect on the ‘finest’ temperature for every filament sort. The hotend temperature is the one parameter diversified within the first set of assessments. Further assessments are carried out after the ‘finest’ hotend temperature is set. These assessments concurrently range totally different parameters to find out tensile power 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 attributable to connection or software program points, and the usage of 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 power between the 2 printers is as a result of inherent variability within the course of. These assessments 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 carried out on the tensile power of the specimens after tensile testing. The impact of utilizing two separate printers will not be statistically important on the 0.05 significance stage (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 applicable to think about the printers as equal.
A number 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, akin to print pace, are generated from the Prusa i3 MK2 profile on Prusa’s official web site. Any remaining settings are chosen from previous expertise and data from the Valpo workforce.
Desk 3: A number of the slicer baseline slicer settings used within the first set of assessments.
3.3 Willpower of Minimal Hotend Temperature
Minimal hotend temperature for every sort of filament is set from evaluation of each the height load and power to weight ratios. Most temperature assessments begin at 15 °C under the MatterHackers common advisable hotend temperature; nonetheless, in some instances after knowledge 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 no less than 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 typical 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 pace 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 characterize the typical for specimens printed at or above the minimal advisable hotend temperature.
A comparability of the experimentally decided tensile properties for every respective filament sort is introduced 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, power to weight ratio, and pressure at failure are all averages of specimens that meet or exceed the minimal recommended hotend temperature. The models of lbf/g are chosen for the power to weight ratio attributable to customers’ familiarity with lbf and the widespread apply of measuring filament/prints in grams.
These numbers will not be meant to foretell the power of a person’s particular printed half. The outcomes are merely used to find out the relative power of 1 filament to a different. This permits a wider viewers to use the teachings discovered in the direction of their very own prints. The advanced nature of FFF printed components requires a extra advanced evaluation of stress concentrators, loading course/sort/fee, and the consequences of working temperature/humidity/age/and many others… 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 reveals the hotend-temperature power to weight ratio (S-W) curve for Black MH Construct PLA. The plot reveals that a rise from 185 °C to 200 °C yields a 43% enhance within the power to weight ratio. The graph reveals that after 200 °C the height load stays comparatively fixed; consequently, the advisable minimal hotend temperature for Black MH Construct PLA is 200 °C.
Determine 9: MatterHackers Black MH Construct PLA hotend temperature comparability for a horizontal specimen print orientation.
4.1.2 Black PRO Collection PLA
Determine 10 reveals the outcomes for MatterHackers Black PRO Collection PLA. It’s anticipated that PRO Collection PLA will carry out much like the MH Construct PLA, and above the 200 °C mark the 2 supplies produce comparable outcomes; nonetheless, PRO Collection PLA didn’t expertise the drop off in power under 200 °C. The authors suggest printing with no less than 200 °C for this explicit printer setup as a result of slight enhance within the S-W ratio; nonetheless, it doesn’t seem that there shall be a big discount within the half power for this testing orientation under 200 °C.
Determine 10: MatterHackers Black PRO Collection PLA hotend temperature comparability for a horizontal specimen print orientation.
4.1.3 Black PRO Collection ABS
Black PRO Collection ABS filament produced the weakest prints with most failing under 400 lbf. Determine 11 reveals the inconsistent S-W ratio pattern for the examined hotend temperatures. One concern with printing the ABS specimens is that warping of the specimens happens for many batches. It’s potential that the specimens carry out poorly throughout tensile testing attributable to residual stresses induced by the uneven cooling, and a rise within the ambient temperature may scale back this impact. Further assessments past the preliminary ten specimens will not be carried out as a result of challenges in printing ABS with the present setup. The Valpo workforce is hesitant to make a suggestion with out further assessments in an elevated temperature printing atmosphere, however the specimens printed at 220 °C demonstrated the best peak load and best ductility; due to this fact, that’s the present recommended minimal hotend temperature.
Future assessments on all filament sorts will reveal what enhancements within the tensile power are available with an elevated ambient temperature.
Determine 11: MatterHackers Black PRO Collection ABS hotend temperature comparability for a horizontal specimen print orientation.
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 workforce to counsel a minimal hotend temperature of 240 °C. You will need to word 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 as a result of form of the stress-strain curve. The upper extrusion temperature and slight variability of samples leads the Valpo workforce to hypothesize that further good points in power could also be discovered with a rise within the ambient print temperature.
Determine 12: MatterHackers Crimson PRO Collection PETG hotend temperature comparability for a horizontal specimen print orientation.
4.1.5 Blue PRO Collection Nylon
Nylon is broadly thought of as a comparatively ductile polymer. MatterHackers Blue PRO Collection Nylon carried out as anticipated with the best ductility ranking of all filaments by greater than 100%. PRO Collection Nylon’s most attention-grabbing 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 the next hotend temperature earlier than the failure mode dies out. Determine 13 reveals that the S-W ratio dips at 250 °C and the Valpo workforce 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 recommended minimal hotend temperature for PRO Collection Nylon on this explicit setup is 245 °C.
Determine 13: MatterHackers Blue PRO Collection Nylon hotend temperature comparability for a horizontal specimen print orientation.
4.1.6 NylonX
Maybe probably the most attention-grabbing 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 workforce attributes this to an open print mattress atmosphere relatively 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 ranking after the 260 °C mark. Using a hardened metal nozzle of 0.4 mm allowed the workforce 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 workforce printed at greater hotend temperatures than different filaments. Determine 14 reveals that rising the hotend temperature from 255 °C to 260 °C leads to a 55% enhance within the S-W ratio. The recommended hotend temperature for NylonX with a hardened metal nozzle is no less than 260 °C.
Determine 14: MatterHackers NylonX hotend temperature comparability for a horizontal specimen print orientation.
4.2 Further Exams
Figuring out minimal hotend temperatures is a vital side of FFF printing, nevertheless it doesn’t embody all the components that have an effect on print power. The Valparaiso College workforce realizes that the tensile power of components printed within the earlier part are depending on further components akin to half fan cooling, z-layer peak, variety of outlines, variety of high/backside layers, infill proportion, and print pace. An in-depth evaluation of all these components 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 assessments with Black MH Construct PLA.
The usage of an element 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 power for layers to bond. Testing this impact on the tensile power 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 reveals that printing with the half fan off produces a statistically important impact on the height load; nonetheless, the rise in power is barely 5%. The fan’s low impression on half power signifies that the fan can be utilized with a statistically important, however minimal impact on the power of PLA components.
4.2.2 Layer Top
Lowering the layer thickness can have a optimistic impact on the beauty look of a printed half, however it could possibly additionally enhance the general print time. These are comparatively straightforward outcomes to foretell with fashionable slicer outputs, however the impact on mechanical power 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. Further assessments are run with 0.1 mm layers to find out if the thinner layers have a statistically important impact on the tensile power. One further modification to the baseline g-code is to regulate the variety of high 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 reveals the outcomes of the layer peak take a look at, and the 0.3 mm and 0.1 mm tensile outcomes are statistically comparable. Further assessments are obligatory to enhance the statistical certainty that layer peak doesn’t have an effect on the tensile power of specimens, however these preliminary assessments counsel that it doesn’t play a big function.
Desk 6: Tensile outcomes for layer peak assessments with Black MH Construct PLA.
4.2.3 Outlines or Prime/Backside Layers
Including materials to printed components can enhance the general power. The person can add outlines, high/backside stable layers, or enhance infill proportion, however which technique of addition is best in rising power? The Valpo workforce 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 as a result of comparable specimen weight in comparison with the opposite two modified specimens.
Evaluation of the leads to Desk 7 demonstrates that a rise within the power to weight ratio is feasible with outlines and stable layers, however that rising the infill proportion didn’t have a statistically important impact. You will need to word that the kind of loading and print geometry is crucial to the place materials needs to be added. Compressive hundreds or advanced geometry might shift the essential areas. Future assessments with totally different loading configurations might shine mild on these results.
Desk 7: Tensile power 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. Further infill percentages should be investigated to find out if the rise in power follows a pattern.
Determine 15 shows p.c infill versus peak load for specimens present process tensile loading. This graph reveals that from 50% to 80% infill the slope for rising power is comparatively shallow; nonetheless, the slope is roughly 4 occasions larger above 80% infill. That is doubtless attributable to elevated bonding between infill traces. These outcomes will should be repeated for different geometries and hundreds, akin to pure compression, to definitively state a larger enhance within the peak load is noticed for the 80-100% infill vary.
Determine 15: MatterHackers Black MH Construct PLA and Black PRO Collection PLA p.c infill versus peak load.
4.2.5 Print Pace
Print pace is one other issue that sometimes has an impact on the person expertise. The flexibility to print ever sooner is a requirement on the FFF business, however the impact of this enhance in print pace on half power is usually missed.
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 sooner. Further pace take a look at outcomes are proven in Determine 16. Black MH Construct PLA reveals no statistically important lower in power when rising the pace 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 much like MH Construct PLA it decreases at 4800 mm/min. Solely the top person can decide if this lower in power is suitable, and if there are further beauty results from printing at these greater speeds. The impact of accelerating print pace will doubtless change primarily based on the geometric accuracy of printers at greater speeds, and on the power of the hotend-nozzle mixture to switch ample vitality into the extruded filament.
Determine 16: Black MH Construct PLA and Black PRO Collection PLA print pace versus power.
4.3 Abstract of Check Outcomes
Desk 8: Comparability of MatterHackers filaments.
Desk 8 reveals the relative rankings of peak load, power to weight ratio, ductility, and isotropic (non-directionality of power). Analyzing the desk reveals that MH Construct PLA and PRO Collection PLA are wonderful basic use filaments for the typical person. They’ve excessive peak hundreds, and exhibit the most effective isotropic ranking. The principle 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 assessments with the bottom peak load, S-W ratio, and comparatively low ductility. These outcomes, coupled with the problem of warping specimens, make it arduous to suggest ABS for this printer setup. The emission of styrene whereas printing ABS additional reduces the attractiveness of this filament sort [3]. The Valpo workforce believes that the appearance of newer filament sorts eliminates the necessity for ABS within the shopper 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 ranking and the second highest isotropic ranking. There are nonetheless challenges related to printing in PETG, akin to the upper extrusion temperature, however total PETG has the potential to problem PLA as the first filament sort.
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 recommended filament. NylonX then again is extra appropriate for weight-dependent purposes, like customized drone components.
[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 workforce at Valparaiso College is working to tell the patron FFF group on how slicer settings, significantly hotend temperature, have an effect on tensile properties of various filament supplies. The outcomes can dispel many conventional myths relating to shopper FFF printing, and they’re going to hopefully help each skilled and novice 3D printer customers in figuring out probably the most relevant filament for his or her challenge. FFF printers have many variables that have an effect on half power exterior of simply the slicer settings; due to this fact, it’s not advisable to make use of this knowledge to estimate the power of printed components. As an alternative, the analysis workforce suggests you take a look at the relative values to find out how totally different filament sorts will doubtless carry out by yourself printer. Probably the most applicable slicer settings for different hotend fashions, filament diameters, nozzle diameters, and many others.… might range broadly. The Valpo workforce hopes the outcomes introduced on this report encourage customers to think about how all these variables may have an effect on printed components, and the workforce hopes future experiments will solely enhance parameter consciousness.
The Valpo workforce is all the time on the lookout for methods to help the patron FFF group. You’ll be able to vote on the following space of analysis by visiting our social media accounts on the following web page!
ABOUT THE ACCELERATED 3D PRINTING LAB AND VALPARAISO UNIVERSITY
The Accelerated 3D Printing Lab is positioned within the School of Engineering at Valparaiso College. Engineering at Valpo is an undergraduate solely program that’s persistently ranked within the high 20 undergraduate engineering applications within the nation by U.S. Information & World Report. The Accelerated 3D Printing Lab was established within the Summer season of 2018 to help Valpo’s additive manufacturing analysis. College students examine a wide range 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 power of components. The outcomes on this paper wouldn’t be potential with out their arduous work and dedication. Dr. Daniel Blood, Assistant Professor of Mechanical Engineering and Bioengineering at Valpo, oversaw the work carried out by Sam and Trevor.
Further due to Kelsey Unser, Rima Miller, Tyler Smar, and William Foy for his or her assist in organising 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 workforce appreciates MatterHackers’ donation of filament for these assessments, and likewise 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