Determination of mechanical properties of plastic components made by 3D printing

Decembe 2022, Vol. 22, No. 6 M ANUFACTURING T ECHNOLOGY ISSN 1213–248 9 733 indexed on: h p://www.scopus.com DOI: 10.21062/m .2022.082 © 2022 Manu ac u ing Technology. All igh s ese ed. h p://www.jou nalm .com De e mina ion o Mechanical P ope ies o Plas ic Componen s Made by 3D P in ing Jose Sedlak (0000-0002-9819-8259)1, Zdenek Joska (0000-0001-6474-789X)2, Lucie H backo a (0000-0003-2498- 5492)1, E a Ju icko a (0000-0002-8018-7391)1, Denisa H usecka (0000-0003-1459-0040)1, Ond ej Ho ak3 1Tomas Ba a Uni e si y in Zlín, Facul y o Managemen and Economics, Depa men o Indus ial Enginee ing and In o ma ion Sys ems, Mos ni 5139, Zlin 760 01, Czech Republic. E-mail: [email p o ec ed], lh back[email p o ec ed], [email p o ec ed], h usecka@u b.cz 2 Uni e si y o De ence in B no, Facul y o Mili a y Technology, Depa men o Mechanical Enginee ing, Kouni- co a 65, B no 602 00, Czech Republic. E-mail: [email p o ec ed] 3Badalky 269, Lysice 679 71, Czech Republic. E-mail: [email p o ec ed] The p esen ed a icle deals wi h he de e mina ion o selec ed mechanical p ope ies o addi i e ma e ials used o 3D p in ing (PETG, PLA, ABS, ABS +, PLA ESD, ASA, PC / ABS). Due o he ac ha 3D p in ing has exploded o e ecen yea s and addi i e manu ac u ing has become popula in some in- dus ies, he quali y o inpu ma e ials and hei mechanical p ope ies is ex emely impo an . We used 3D p in e O iginal P usa MK3 o p epa e samples o es ing. Indi idual samples p in ed om all abo e men ioned ma e ials we e analyzed using selec ed mechanical es s (s a ic ensile es , ha dness es s). In he s a ic ensile es , selec ed pa ame e s ( ensile s eng h limi , ensile modulus, elonga ion) we e de e mined o all addi i e samples, which we e s a is ically p ocessed. The pa ame e s o wo me hods o measu ing ha dness we e also s a is ically e alua ed, namely Sho e and ball inden a ion. All es ed addi i e ma e ials we e compa ed wi h he aim o ob aining he inal anking (poin e alua ion o es ed ma e ials wi h quan i ica ion o p ice cos s). The bes p ope ies a e he pe o med es s we e achie ed by he addi i e ma e ial PLA Filamen Plas y Mladeč. Keywo ds: Adi i e manu ac u ing, 3D p in ing, Fused ilamen ab ica ion, Mechanical p ope ies, Tensile es , Ha dness es s In oduc ion The complex geome y o he inal p oduc was always he bigges p oblem o designe s, un il he ad- en o Rapid P o o yping addi i e echnology. Rapid P o o yping echnology, also known as 3D p in ing, consis s o se e al me hods de eloped in he la e 1980s. Fo a long ime, his echnology was used only in cons uc ion and in a p o essional indus ial en i- onmen o c ea e p o o ypes o e en inished com- ponen s. 3D p in ing is a e y b oad concep ha inc- ludes many p oduc ion me hods. One o hem is he addi i e me hod Fused Filamen Fab ica ion (FFF) [1], [2]. In ecen yea s, he si ua ion has changed sha ply and 3D p in ing has been g adually made a ailable o o dina y use s / consume s hanks o educed acqui- si ion cos s. Thanks o his, new p in ing me hods de- eloped apidly. Addi i e ma e ials used in 3D p in- ing a e also unde going g ea de elopmen [2], [3]. Nowadays, 3D p in ing echnology o e s a wide po - olio o addi i e ma e ials. In addi ion o he basic po- lyme ic ma e ial, o example, a ce amic, me al o composi e addi i e ma e ial is also used. A he same ime, he 3D p in ing echnology i sel has ad anced and is used mo e in o he a eas han jus in he posi- ion o enginee ing. 3D p in ing has been widely used, o example, in he ield o medicine (implan p oduc ion), pha macy (d ugs), enginee ing, cons uc ion, ood, bu also in he au omo i e, ae ospace, ene gy, consume in- dus ies, e c. [3], [4]. 3D p in ing echnology is no lon- ge only used o he p oduc ion o p o o ypes and hei es ing p io o pu ing in o p oduc ion, bu also as an independen p oduc ion echnology in ce ain sec o s whe e he echnological p ocess and o he ci - cums ances allow. I is o his eason ha e e highe demands a e placed on he quali y o he ma e ial used, i s mechanical p ope ies, heal h sa e y (in heal hca e), and o he pa ame e s acco ding o he ype o indus y in which he inal p oduc is o be used. Many au ho s in hei s udies compa ed de o es jus indi idual pa a- me e s o he ma e ials in es iga ed in o de o assess hei sui abili y o a pa icula pu pose. One o he mos commonly used ma e ials o 3D p in ing is ABS (Ac yloni ile-bu adiene-s y ene). Raney e al. [5] es- ed he ensile s eng h o his ma e ial and ound ha he ensile o ce measu ed agains he laye s is only 74% o 79% o he o ce measu ed along he laye s. Decembe 2022, Vol. 22, No. 6 M ANUFACTURING T ECHNOLOGY ISSN 1213–248 9 indexed on: h p://www.scopus.com 734 Dizon e al. [6] made an ex ensi e esea ch in he ield o es ing mechanical p ope ies o ma e ials o 3D p in ing, du ing which ound ha he es c i e ia and he whole es ing p ocess is e y di e en in di e- en esea ch g oups and o en also depends on he pu pose o he use o esul ing 3D p in ing p oduc s. So a , he e is no s anda dized p ocedu e o es ing he mechanical p ope ies o ma e ials and indi idual s udies di e conside ably om each o he . Mos au - ho s ocus mainly on he ensile s eng h o ma e ials [5], [7], [8], [9], [10] and shea [11] o de o ma ion caused by p essu e [12], o he s ocus on some o he mechanical p ope ies such as " olding beha io " [13] o ac u e models du ing comp ession loading [14]. Fu he s udies a e de o ed o examining he spe- ci ic p ope ies o addi i e ma e ials o a speci ic pu - pose. Fo example, Alssabbagh e al. [15] analyzed nine ma e ials (including common ones such as PLA, ABS, e c.) o e alua e he mass a enua ion coe icien and selec he mos sui able ma e ial o eplace human so issue. Mos au ho s in hei s udies es he mos common ma e ials used o 3D p in ing (such as ABS, PETG o PLA). In p ac ice, howe e , he e a e also coun less special ma e ials o 3D p in ing o a ious special pu poses (ae ospace indus y, medicine, ene gy, e c.). Fo example, Zaldi a e al. [16] o Kap- lun e al. [17] in es iga ed he e ec o 3D p in ing on he mechanical and he mal p ope ies o one o he mos du able polyme s used o 3D p in ing ULTEM® 9085. The esul s we e compa ed wi h plas ic injec ion echnology, whe e he s eng h o he examined samples was demons ably highe by abou 40%. In addi ion o he ype o ma e ial, he mechanical p ope ies o addi i e p oduc ion p oduc s (3D p in- ing) a e also a ec ed by he p oduc ion p ocess i sel . Acco ding o he indings o Dizon e al [6], he bes ensile p ope ies a e achie ed when he ilamen is placed longi udinally, ie pa allel o he loading di- ec ion. Melenka e al [7] in u n es ed he elas ici y o he sample depending on he ibe olume ac ion and Sood e al [18] assessed he in luence o i e im- po an p ocess pa ame e s ( hickness o one ibe la- ye , o ien a ion, angle and wid h o he as e and ai gap) on he ensile, lexu al and impac s eng h o he sample. The esul s o esea ch on quali y pa ame e s (dimensions and su ace quali y) ca ied ou on 3D p in ing p oduc s p oduced by he DMLS me hod poin o compliance wi h he s a ed quali y o he p o- duc ion echnology and an e en dis ibu ion o i egu- la i ies in su ace oughness measu emen s [19]. In ou a icle, we ocus on he mechanical p ope - ies o addi i e ma e ials ha a e commonly used o 3D p in ing in bo h indus ial p oduc ion and hobby en i onmen s. In addi ion o he ensile s eng h o he sample, hei ha dness is also es ed in he o m o he esis ance o he sample su ace o he sc a ching o ano he , ha de ma e ial. This ype o es is mos ly neglec ed in he abo e esea ch, bu i is no less im- po an o he quali y o p oduc s p oduced by 3D p in ing echnologies [20]. Pa o he p esen ed s udy is also an economic e alua ion o all he mos commonly a ailable a ian s o ma e ials. In ecen yea s, 3D p in ing echnology has become qui e es a- blished in mo e echnologically ad anced indus ies and, oge he wi h he use o new ma e ials, makes i possible o imp o e he p ice / quali y a io and hus ensu e g ea e compe i i eness o he company [21]. Fused ilamen ab ia ion echnology Fused Filamen Fab ica ion (FFF) is a p in ing me- hod whose p oduc ion p ocess consis s o mel ing he inpu ma e ial. The ilamen wound on he spool is p essed by means o an injec ion mechanism ( wo gea s connec ed o he mo o ) in o a hea ed nozzle, in which i is mel ed in o a semi-liquid s a e. The mol en ma e ial is hen applied in indi idual laye s o a hea ed subs a e, whe e i is cooled by ambien ai un il i so- lidi ies. P in ing o one laye akes place simul a- neously in X and Y coo dina es. A e he end o one laye , he p in head wi h he nozzle mo es in he Z axis by he laye hickness upwa ds and a new laye is p in ed. In his way, he whole p ocess is epea ed un- il he esul ing objec is c ea ed. A he end o he p o- duc ion p ocess, i is necessa y o emo e he p in ing suppo s [22], [23], [24]. De o ma ion o he PLA ma- e ial can be caused depending on he hea ing o he p in ing pad and he solu ion can be o cu he objec du ing he p in ing p ocess [25]. Filamen as an inpu ma e ial is made o many y- pes o ma e ial. The addi i e FFF me hod equi es p in suppo o complex shapes ha a e c ea ed in he same way as he esul ing model, wi h only a lowe ill densi y and ewe edge loops. P in suppo s can be p in ed om he same ma e ial as he esul ing mo- del, o a special wa e -soluble building ma e ial. P o- o ype models p oduced by his me hod a e used in design es ing o p oduc inno a ion. Models can also be exposed o mechanical and wea he condi ions co esponding o eali y [22], [23], [24]. The densi y o he PLA ma e ial is also a ec ed by he densi y o he sample illing, which was es ed by a ensile es , his es con i med ha he shape o he ille does no a ec he alues ob ained by he ensile es [26]. The main ad an ages o FFF echnology a e mini- mal was e (suppo s), high p in ing speed and good mechanical p ope ies [22], [23]. Disad an ages inc- lude limi ed dimensional accu acy depending on he ma e ial used, p in nozzle diame e , and suscep ibili y o sh inkage du ing cooling. [22], [23], [28]. In he ex- pe imen , he ensile s eng h was es ed using he highe and lowe empe a u e limi s speci ied by he manu ac u e o PLA, PETG and ABS ma e ials, and Decembe 2022, Vol. 22, No. 6 M ANUFACTURING T ECHNOLOGY ISSN 1213–248 9 735 indexed on: h p://www.scopus.com i is app op ia e o use he uppe limi o he empe a- u es ecommended by he manu ac u e [27] . S a ic ension es and ha dness es s In his pa o he pape , selec ed mechanical es s, which we e subsequen ly applied in he expe imen al pa , will be cha ac e ized. S a ic ension es The s a ic ensile es is one o he mos o en used mechanical es s. The p inciple o he ensile es is p esc ibed by he ČSN EN ISO 527-2 s anda d. The es is usually pe o med a oom empe a u e (23 ºC). I is used o de e mine he ensile s eng h Rm, he yield s eng h Re, he con ac ual yield s eng h Rp0,2, he ensile modulus E and o he ensile s ess-depen- den cha ac e is ics. [29], [30]. The ul ima e s eng h Rm is he s ess alue ea- ched a maximum load be o e he es ba up u es. The alue o Rm is a signi ican ma e ial alue, classi- ying indi idual ypes o ma e ials and is de e mined acco ding o ela ion (1) [31], [32], [33]: 𝑅  𝐹  𝑆  󰇟𝑀𝑃𝑎󰇠, (1) Whe e: Rm…S ess a he limi o s eng h [MPa], Fm…Maximum load o ce [N], S0…Ini ial c oss-sec ion o he sample [mm2] [34]. Hooke's law ep esen s he ela ionship be ween s ess and ela i e elonga ion, see ela ionship (3). In he con ac ile ensile diag am, Hook's law is plo ed as a s aigh line. The di ec ion o he line is gi en by he modulus o elas ici y in ension E and can be ex- p essed by equa ion (2) [31], [32], [33]: 𝐸 an 󰇛𝛼󰇜, (2) Whe e: E…Modulus o elas ici y in ension [MPa], α…Angle o he line wi h ho izon al axis [º], S0…Ini ial c oss sec ion o he sample [mm2] [34], [35], [36]. 𝜎𝐹 𝑆𝐸∙ΔL L  𝐸∙𝜀󰇟𝑀𝑃𝑎󰇠, (3) Whe e: σ…Tensile s ess [MPa], F…Loading o ce [N], S…Ac ual c oss sec ion o he sample [mm2], E…Modulus o elas ici y in ension [MPa], ΔL…Change in he leng h o he es sample [mm], L0…Ini ial sample leng h [mm], ε…Rela i e elonga ion [-] [34], [35], [36]. Elonga ion (Ax) de e mines he scale o o mabili y o he ma e ial. The alue o duc ili y can be de e mi- ned om ε a e he up u e o he es ba by equa ion (4) [32], [33]. 𝐴  100∙       100∙     󰇟%󰇠, (4) Whe e: AX…Elonga ion [%], Lu…Final leng h [mm], L0…Ini ial leng h [mm], ΔLu…Absolu e inc emen o ini ial leng h a e up u e [mm] [32]. The index (x) ep esen s he ype o es od. Fo sho es ba s, "x" is no gi en. Fo long es ba s, he duc ili y is indica ed A11,3. The duc ili y o he ma e ial measu ed on he disp opo iona e es ba s is indica- ed ela i e o i s ini ial leng h (L0 = 50 mm is deno ed A50). The sho e he es od, he highe he duc ili y alue [32], [33]. The ac u e o he es ba mus be in he middle hi d o he measu ed leng h. I he qua y is loca ed in ano he a ea, he measu ed alue o Ax may di e om he ac ual [32], [33]. Ha dness es Ha dness is he mos commonly used es de ining he mechanical p ope ies o a polyme ic ma e ial. The esis ance o he su ace o he pene a ion o ano he ha de ma e ial is de ined and he ma e ials a e di ided in o igid, ha d and ough. The measu emen o ha d- ness by he pene a ion me hod is in p inciple he in- den a ion o an pene a ing body (inden e ) o a ious shape by a p ede ined o ce in o he su ace o he es- ed ma e ial. The measu emen me hod is di ided ac- co ding o he shape o he inden e (ball, cone). A e a de ined ime in e al, he pene a ion dep h o he inden e is hen measu ed. In he case o plas ic ma e- ial, bo h plas ic and elas ic de o ma ion a e aken in o accoun [32], [37], [38], [39]. Fig. 1 Ha dness measu emen by he ball inden a ion me hod [26] Decembe 2022, Vol. 22, No. 6 M ANUFACTURING T ECHNOLOGY ISSN 1213–248 9 indexed on: h p://www.scopus.com 736 The ball inden a ion me hod is de ined by he s an- da d ČSN EN ISO 2039-1: Plas ics - De e mina ion o ha dness - Pa 1: The ball inden a ion me hod is a measu emen me hod in which a ha dened s eel ball o diame e D (5 mm) is p essed in o he es ma e ial, see Fig. 1 [30], [40], [41]. The es specimen is i s loaded wi h an ini ial load o 9.8 N and hen wi h a es load o 49 N o 961 N. The magni ude o he es load depends on he esul- ing inden a ion dep h, which mus be be ween 0.15 mm and 0.35 mm. The ha dness is ead a e 30 s o measu emen and calcula ed acco ding o equa ion (5) [30]: 𝐻𝛼∙   , 󰇟Nmm  󰇠, (5) Whe e: α…Fac o (0,0535) [mm-1], FC…To al load [N], h…Dep h o pene a ion o he ball in o he ma e- ial [mm], H…Ball inden a ion ha dness [N·mm-2] [30]. Sho e ha dness is one o he mos common ha d- ness measu emen s in p ac ice. Acco ding o he ha d- ness ange, a dis inc ion is made be ween Sho e A ha dness measu emen s, used o so e ma e ials, and Sho e D, o ha de ma e ials. Sho e A and Sho e D measu emen me hods di e in he shape o he in- den ed ip. The ips a e p essed in by a sp ing. The dep h o which he measu ing ip is p essed de e mi- nes he deg ee o ha dness. The ha dness o he plas ic ma e ial akes on alues in he ange 0 o 100 HSh o he Sho e me hod [30]. The hickness o he es ma e ial mus be a leas 6 mm o bo h me hods. When measu ing wi h he Sho e A me hod, he alue is ead a e 3 s (measu ed om he i s con ac wi h he su ace) and he ha d- ness by he Sho e D me hod is ob ained a e 15 s o he measu emen [30]. Expe imen al pa Indi idual es specimens we e made on an FFF 3D p in e O iginal P usa MK3. The p in ing pa ame- e s o he indi idual ypes o ma e ials we e chosen wi h ega d o he in o ma ion ob ained om he ma- e ial shee s and da a o indi idual manu ac u e s (ex- ude and pad empe a u e). O he necessa y pa ame- e s, such as p in speed, ex usion and cooling, a e p ede ined by he p in e manu ac u e and a e al eady in he P usaSlice compu e so wa e. Tab. 1 Addi i e ma e ials used [41], [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53] Ma e ial P oduce Rm [MPa] E [MPa] A [%] Ha dness [HRH] ABS P usa - - - - ABS+ De il Design - - 30 105 PC/ABS Filamen Plas y Mladeč - - - - ASA De il Design - - 20 107 Filamen Plas y Mladeč - - - - Fillamen um 40 1726 35 92 PETG Filamen Plas y Mladeč - - - - P usamen - 1500 - - Spec um 27,1 360 9,5 - PLA Filamen Plas y Mladeč - - - - Fillamen um 53 3600 6 - P usamen - 2200 - - PLA ESD 3DXSTAT 55 2560 10 - Filamen s wi h a diame e o 1.75 mm we e chosen o he 3D p in e used. In addi ion o di e en ypes o addi i e ma e ial, ma e ials om se e al supplie s a e es ed. The addi i e ma e ials used, including supplie s and basic mechanical p ope ies, a e lis ed in Tab. 1. The es specimens we e p in ed ho izon ally wi h 100 % inne ill and h ee ci cum e en ial pe ime- e s. P epa a ion o es samples 4.1.1 S a ic ensile es The shape and dimensions o he es specimen we e chosen acco ding o he ČSN EN ISO 527-2 s anda d. This s anda d speci ies he condi ions o es ing o plas ic ma e ial and he de e mina ion o hei mechanical p ope ies in he ensile es . The s anda d was chosen despi e he ac ha i desc ibes es specimens c ea ed by injec ion molding, p essing o cas ing because he e is s ill no s anda d ha would Decembe 2022, Vol. 22, No. 6 M ANUFACTURING T ECHNOLOGY ISSN 1213–248 9 737 indexed on: h p://www.scopus.com desc ibe he ensile es o samples c ea ed by 3D p in- ing echnology [55], [56]. Fo he ensile es , acco ding o he s anda d ČSN EN ISO 527-2, a es od ma ked 1BA was chosen, see Fig. 2. The 1BA es od was chosen due o he sa ings o he used addi i e ma e ial o p oduc ion and sho e 3D p in ing ime [55], [56]. Fig. 2 Dimensions o ensile es ba Fo be e s a is ical e alua ion o ensile es s, 5 pieces o es ods we e made om each ype o ma- e ial and supplie . The o al p in se ies was 65 pieces. 4.1.2 Sho e ha dness es The shape and dimensions o he es specimen o measu ing he Sho e ha dness we e chosen acco ding o EN ISO 7619. This s anda d speci ies he condi i- ons o es ing specimens made o ubbe , ulcanized o he moplas ic elas ome . The dimensions o mea- su ing Sho e ha dness a e shown in Fig. 3. Fig. 3 Sho e ha dness es specimen 4.1.3 Ball inden a ion es Nei he he shape no he dimensions o he es specimen o measu ing he ha dness by he ball in- den a ion me hod a e p esc ibed in any exis ing s an- da d. Fo es specimens, i is impo an o ha e a su icien heigh so ha he measu ed ha dness o he es specimen is no a ec ed in any way by he ha d- ness o he base o he measu ing de ice. The dimen- sions o he es specimen o measu ing ha dness by ball inden a ion a e shown in Fig. 4. Fig. 4 Tes specimen o measu ing he ha dness o inden a- ion by a ball Ca ying ou mechanical es s 4.2.1 S a ic ensile es The ensile es was pe o med on a Zwick Z100 es ig. The es equipmen is connec ed o he com- pu e uni in which he es p og am XX supplied by Zwick is loca ed ia a cable. The p og am also se es o e alua e he cou se o ensile es s and he esul ing pa ame e s (yield s eng h, yield s eng h, modulus o elas ici y and plo ing he cou se o eco ds om he ensile es ). A he beginning o he measu emen , i was ne- cessa y o se he inpu da a. I was he dis ance be ween he clamping jaws, which was 60 mm, and he inpu dimensions o he na owed pa o he es ba s. A e he es od has been co ec ly a ached be ween he jaws, i is possible o s a a es measu emen using he compu e p og am es Xpe . The es is au oma- ically e mina ed a e he es ba up u es. The p o- g am eco ds and hen e alua es he indi idual ensile p ope ies o he ma e ial, which a e expo ed o Excel o u he s a is ical e alua ion. 4.2.2 Sho e ha dness es The Sho e D me hod was used o measu e ha d- ness, which allows measu ing plas ic ma e ials in he ha dness ange o 10 o 90 HShD. The ha dness o he es specimens was measu ed on a Digi Tech ha dness es e . A es specimen is placed on he suppo o he es equipmen . A e s a ing he measu emen , he inden e is p essed in o he es specimen o 15 s. A - e he ime has elapsed, he esul ing measu ed ha d- ness is displayed on he ou pu de ice. 4.2.3 Ball inden a ion es Ball ha dness measu emen e y unique. A special measu ing de ice is equi ed o measu e he ha dness, and he e o e i was necessa y o pe o m he es in coope a ion a he Ins i u e o Tes ing and Ce i ica- ion based in Zlín. The measu emen o he ha dness Decembe 2022, Vol. 22, No. 6 M ANUFACTURING T ECHNOLOGY ISSN 1213–248 9 indexed on: h p://www.scopus.com 738 o he inden a ion by he ball was pe o med on one piece o es specimen wi h i e epe i ions. E alua ion o esul s achie ed The expe imen ally ob ained da a we e e alua ed o indi idual es measu emen s sepa a ely, including a compa ison o he alues gi en by he supplie in he ma e ial shee s. The e alua ed pa ame e s include he ensile s eng h, ensile modulus, elonga ion, Sho e ha dness and ball inden a ion ha dness. The ob ained da a we e indi idually e alua ed using he s a is ical so wa e Mini ab. Fi s , he Ande son-Da ling No - mali y Tes was used o de e mine whe he o no he da a had a no mal dis ibu ion. The assump ion o no mally dis ibu ed da a is equi ed when calcula ing s a is ical pa ame e s and he Ano a es . In gene al: i he P- alue is less han 0.05, da a wi h a eliabili y g e- a e han 95 % do no ha e a no mal dis ibu ion. In his case, i is impo an o dele e some alues. O he wise, he da a can be u he p ocessed and he mean, mean, e o , s anda d de ia ion, median, mi- nimum, maximum and con idence in e al de e mi- ned using he One-Sample T- es . Tab. 2 shows he basic s a is ically e alua ed pa a- me e s and hei alues o he ABS addi i e ma e ial. The e alua ion o all addi i e ma e ials was pe o med in he same way as o he ABS addi i e ma e ial. Wi h a ew excep ions, he ma e ial shee s do no con ain, see Tab. 1, no mechanical p ope ies speci ied by he supplie [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54]. Tab. 2 Basic s a is ical pa ame e s o ABS addi i e ma e ial Pa ame e s Tensile s eng h alues Tensile modulus alues Elonga ion alues Sho e ha dness alues Ball inden a ion ha dness alues Mean alue 37.82 MPa 748.92 MPa 6.88 % 76.73 HShD 55.24 N·mm-2 Mean alue e o 0.20 88.31 0.18 0.21 1.23 S . de ia ion 0.46 197.46 0.41 0.87 2.75 Median 37.84 MPa 787.55 MPa 6.76 % 76.90 HShD 55.90 N·mm-2 Minimum 37.20 MPa 438.11 MPa 6.50 % 74.70 HShD 51.80 N·mm-2 Maximum 38.42 MPa 920.15 MPa 7.56 % 77.70 HShD 58.20 N·mm-2 Reliabili y le el (95,0 %) 0.93 0.36 0.26 0.15 0.53 Con idence in e al 37.25 MPa 38.39 MPa 503.70 MPa 994.10 MPa 6.37 % 7.39 % 76.27 HShD 77.18 HShD 51.82 N·mm-2 58.66 N·mm-2 Discussion on achie ed esul s The g aphical dependence on Fig. 5 shows he mean alues o he pa ame e Rm o indi idual ypes o addi i e ma e ials, including hei con idence in e - al. F om he g aphical dependence on Fig. 5 i is e i- den ha he ensile s eng h Rm o se e al ma e ials exceeds he o he s. This is he case, o example, wi h PC / ABS and PLA ma e ials, ega dless o he supplie (o he ma e ials do no each he Rm alues o hese ma e ials). Acco ding o he compa ison and pe o med analysis o indi idual addi i e ma e ials, o mos o hei Rm alues hey do no each he p esc ibed alue om he ma e ial shee , see Tab. 1. Acco ding o he a ailable and s a ed alues om he ma e ial shee see Tab. 1 and Fig. 5, he max. alue Rm ( o PLA ESD addi i e ma e ial) and he min. Rm a- lue ( o PETG Spec um addi i e ma e ial) is always plo ed [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54]. F om he o e all e alua ion see Tab. 3 and Fig. 5, i can be seen ha he highes alue o he ensile s eng h Rm is eached by he addi i e ma e ial PLA Filamen Plas y Mladeč. Tab. 3 shows he mean alues in he 95 % con i- dence in e al. Decembe 2022, Vol. 22, No. 6 MANUFACTURING TECHNOLOGY ISSN 1213–248 9 739 indexed on: h p://www.scopus.com Tab. 3 Mean alues in he 95% con idence in e al Ma e ial P oduce Rm [MPa] E [MPa] A [%] Ha dness [HShD] Ha dness [N·mm-2] ABS P usa 37.82 748.92 6.88 76.73 55.24 ABS+ De il Design 31.90 906.53 6.20 75.38 85.58 PC/ABS Plas y Mladeč* 55.52 989.74 5.97 76.23 60.78 ASA De il Design 40.38 1086.98 5.33 76.04 73.48 Plas y Mladeč* 40.46 857.67 6.64 75.76 87.20 Fillamen um 34.41 832.67 7.34 71.45 43.00 PETG Plas y Mladeč* 41.90 1053.66 8.65 72.80 67.86 P usamen 45.74 1946.50 5.53 71.79 64.60 Spec um 46.59 1041.46 10.12 74.03 78.15 PLA Plas y Mladeč* 58.61 1684.03 4.83 77.92 118.14 Fillamen um 55.61 1259.19 5.08 81.73 99.56 P usamen 55.98 1551.65 4.67 78.06 92.76 PLA ESD 3DXSTAT 35.62 826.96 16.56 65.75 77.22 *Filamen Plas y Mladeč Fig. 5 Compa ison o ensile s eng h Rm [MPa] The g aphical dependence on Fig. 6 shows he mean alues o he pa ame e E o indi idual ypes o addi i e ma e ials, including hei con idence in- e al. PLA ESD PLA P usamen PLA Fillamen um PLA Filamen Plas y Mladeč PETG Spec um PETG P usamen PETG Filamen Plas y Mlade č ASA Fillamen um ASA Filamen Plas y Mlade č AS A De il De sign PC/ABS ABS+ ABS 60 50 40 30 20 10 0 Rm [MPa] PLA ESD PETG Spec um 37.82 31.90 55.61 55.98 35.62 55.52 40.38 40.46 34.41 41.90 45.74 46.59 58.61 Decembe 2022, Vol. 22, No. 6 MANUFACTURING TECHNOLOGY ISSN 1213–248 9 indexed on: h p://www.scopus.com 740 Fig. 6 Compa ison o modulus o elas ici y in ension E [MPa] F om he o e all e alua ion see Tab. 3 and Fig. 6, i can be seen ha he highes modulus o elas i- ci y in ension E was eached by he addi i e ma e- ial PETG P usamen . The mean alue o he PETG P usamen addi i e ma e ial exceeds he wo PLA ma e ials, and i s con idence in e al is much wide han ha o he PLA ma e ial. Du ing he en- sile es , he PETG ma e ial showed ce ain p o- blems, and he e o e he bes esul in e ms o he modulus o elas ici y in ension E was achie ed by he addi i e ma e ial PLA Filamen Plas y Mladeč. I he alue o he modulus o elas ici y in en- sion E was p esc ibed by he supplie in he ma e ial shee , i s de e mined / measu ed alue did no each he p esc ibed size (excep o he addi i e ma e ial PETG P usamen and PETG Spec um) see Tab. 1 [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54]. Acco ding o he a ailable and s a ed alues om he ma e ial shee see Tab. 1 and Fig. 6, he max. alue E ( o he addi i e ma e ial PLA Filla- men um) and he min. E alue ( o PETG Spec um addi i e ma e ial) is always plo ed [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54]. The g aphical dependence on Fig. 7 shows he mean alues o he pa ame e A o indi idual y- pes o addi i e ma e ials, including hei con idence in e al. F om he g aphical dependence on Fig. 7 i is e iden ha he highes mean alues o duc ili y A each he addi i e ma e ial PLA ESD. Howe e , i s con idence in e al is e y wide, and he e o e i is no app op ia e o conside his ma e ial as he bes in e ms o duc ili y. Fo his eason, he bes elas ic p ope ies a e achie ed by he addi i e ma e ials PLA Filamen Plas y Mladeč and PETG P usamen . Acco ding o he a ailable and s a ed alues om he ma e ial shee see Tab. 1 and Fig. 7, he max. alue E ( o he addi i e ma e ial PLA Filla- men um) and he min. E alue ( o PETG Spec um addi i e ma e ial) is always plo ed [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54]. The g aphical dependence on Fig. 8 shows he mean alues o Sho e ha dness o indi idual ypes o ma e ials, including hei con idence in e al. All ma e ials ha e almos he same ha dness. The highes ha dness alues a e achie ed by PLA Filla- men um and he lowes ha dness alues a e achie- ed by PLA ESD. PLA ESD PLA P usamen PLA Fillamen um PLA Filamen Plas y Mladeč PETG Spec um PETG P usamen PETG Filamen Plas y Mladeč ASA Fillamen um ASA Filamen Plas y Mladeč ASA De il Design PC/ABS ABS+ ABS 4000 3000 2000 1000 0 E [MPa] PLA Fillamen um PETG Spec um 748.92 906.53 1259.19 1551.65 826.96 989.74 1086.98 857.67 832.67 1053.66 1946.50 1041.46 1684.03 Decembe 2022, Vol. 22, No. 6 MANUFACTURING TECHNOLOGY ISSN 1213–248 9 741 indexed on: h p://www.scopus.com Fig. 7 Elonga ion compa ison A [%] Fig. 8 Sho e ha dness compa ison [HShD] The g aphical dependence on Fig. 9 shows he mean alues o he ball inden a ion ha dness o indi- idual ypes o ma e ials, including hei con idence in e al. F om he g aphical dependence on Fig. 9 i is e iden ha he highes ha dness alues a e achie ed by he ma e ial PLA Filamen Plas y Mladeč and he lowes ha dness alues a e achie ed by he ma e ial ASA Fillamen um. PLA ESD PLA P usamen PLA Fillamen um PLA Filamen Plas y Mlade č PETG Spec um PETG P usamen PETG Filamen Plas y Mladeč ASA Fillamen um ASA Filamen Plas y Mlade č ASA De il Design PC/ABS ABS+ ABS 40 30 20 10 0 A [%] ASA Fillamen um PLA Fillamen um 6.88 6.20 5.08 4.67 16.56 5.97 5.33 6.64 7.34 8.65 5.53 10.12 4.83 PLA ESD PLA P usamen PLA Fillamen um PLA Filamen Plas y Mladeč PETG Spec um PETG P usamen PETG Filamen Plas y Mladeč ASA Fillamen um ASA Filamen Plas y Mladeč ASA De il Design PC ABS ABS+ ABS 90 80 70 60 50 40 30 20 10 0 H [HShD] 76.73 75.38 81.73 78.06 65.75 76.23 76.04 75.76 71.45 72.80 71.79 74.03 77.91