Powder Metallurgy

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Debinding behaviour of feedstock for material

extrusion additive manufacturing of zirconia

Christian Kukla, Santiago Cano, Dario Kaylani, Stephan Schuschnigg,

Clemens Holzer & Joamin Gonzalez-Gutierrez

To cite this article: Christian Kukla, Santiago Cano, Dario Kaylani, Stephan Schuschnigg,
Clemens Holzer & Joamin Gonzalez-Gutierrez (2019) Debinding behaviour of feedstock for
material extrusion additive manufacturing of zirconia, Powder Metallurgy, 62:3, 196-204, DOI:
10.1080/00325899.2019.1616139

To link to this article: https://doi.org/10.1080/00325899.2019.1616139

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Published online: 15 May 2019.

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POWDER METALLURGY
2019, VOL. 62, NO. 3, 196–204
https://doi.org/10.1080/00325899.2019.1616139

Debinding behaviour of feedstock for material extrusion additive

manufacturing of zirconia
Christian Kukla a, Santiago Cano b
, Dario Kaylanib, Stephan Schuschnigg b
, Clemens Holzer b
and
Joamin Gonzalez-Gutierrez b
a
Industrial Liaison Department, Montanuniversitaet Leoben, Leoben, Austria; bPolymer Processing, Montanuniversitaet Leoben, Leoben,
Austria

ABSTRACT ARTICLE HISTORY

Material Extrusion Additive Manufacturing (MEAM) is mainly used for the production of Received 29 November 2017
polymeric components. Using feedstocks similar to those of powder injection moulding, Revised 13 August 2018
MEAM of ceramic components is possible. MEAM with filaments is also called Fused Filament Accepted 3 May 2019
Fabrication. Feedstocks are used as filaments; this imposes new requirements such as
KEYWORDS
flexibility for spooling, stiffness to avoid buckling and constant diameter to ensure a Material extrusion; fused
consistent mass flow. Additionally, the binder should be removed without damaging the filament fabrication;
shaped part. In this paper, the debinding behaviour of MEAM feedstocks with zirconia was feedstock; ceramic
investigated. It was observed that higher temperature increases the debinding rate, but
cracks occurred; the addition of a surfactant speeds up the debinding rate and reduces
cracks; and a mixture of 10% isopropanol and 90% cyclohexane initially decreases swelling
during debinding, but the debinding rate and the appearance of cracks is unaffected.

Introduction
the feedstocks. To be spooled as a filament, high flexi-
Fused Filament Fabrication (FFF) is a popular Material bility and strength is required for the feedstock. Since
Extrusion Additive Manufacturing (MEAM) tech- the solid filament must transmit the force from the
nique. The main reasons for its popularity are its safe feeding wheels to the molten feedstock, sufficient stiff-
and simple fabrication process, low cost and the avail- ness is required to avoid its buckling during the material
ability of a great variety of building materials. In FFF, a extrusion process. Furthermore, a low viscosity is
thermoplastic filament is extruded through a nozzle by necessary to reduce the flow resistance, and a good
the action of two counter-rotating feeding wheels and adhesion is necessary between the already extruded
deposited on a plate one layer at a time. The printing and deposited layers as well as to the building platform.
chamber and bed are kept at temperatures below the In order to achieve all these properties in a feedstock,
polymer melting point but higher than room tempera- multicomponent binder systems are required and the
ture to promote adhesion to the printing bed and to right proportion of the components is needed [7,9].
reduce thermally induced stresses [1,2]. Our research group developed a binder system con-
FFF can be used for the production of metallic or sisting of a thermoplastic elastomer for flexibility and a
ceramic parts with complex shape, in a process called grafted polyolefin for stiffness and tackiness. This rela-
Shaping, Debinding and Sintering (SDS) [3] or fused tively simple formulation has been demonstrated to
deposition of metals (FDMet) [4,5] or ceramics produce filaments processable by FFF with various
(FDC) [6–8]. Feedstocks used in SDS consist of a poly- metallic and ceramic powders such as stainless steel
meric binder and a high load of sinterable powder. 316L (d50 = 6.05 µm)[10], titanium alloy Ti6Al4V
After shaping, the binder is removed via solvent extrac- (d50 = 14.97 µm)[11], neodymium alloy NdFeB (d50 =
tion and/or thermochemical decomposition. Finally, 28.29 µm) [11], strontium ferrite SrFe12O19 (d50 =
the powder is sintered together to obtain a solid part. 1.35 µm)[11,12] and yttria stabilised zirconia YSZ
Therefore the content of powders in the feedstock (d50 = 0.6 µm) [11]. In Figure 1, the mechanical proper-
should be equal or higher than 50 vol.-% to reduce ties of filaments made out of feedstocks containing the
shrinkage and defects during the sintering process. In developed binder system and 55 vol.-% of solid content
addition to the requirements of a highly filled system, (except for the zirconia feedstock, with a solid content
the processing by FFF imposes further demands on of 50 vol.-%) are depicted.

CONTACT Christian Kukla christian.kukla@unileoben.ac.at Industrial Liaison Department, Montanuniversitaet Leoben, Peter Tunner Straße 27,
Leoben 8700, Austria
© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-
nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or
built upon in any way.
 POWDER METALLURGY 197

in cyclohexane at 60°C at times up to 12 h is plotted

for the different feedstocks. The highest binder loss
was obtained for 316L feedstock. For short times
(3 and 6 h) a higher debinding rate was obtained for
NdFeB than for Ti6Al4V, nevertheless similar values
were obtained at 9 and 12 h. The feedstocks with the
two ceramic powders showed the lowest values for
the leached soluble binders. Figure 3(b) shows that
the filler used in the feedstock not only affect the
debinding rate, but also can lead to defects during
debinding. All the metal-filled feedstocks could be
debound without defects, but the ceramic ones devel-
oped cracks [11]. The small particle size of the ceramic
Figure 1. Strain-stress (ε – σ) curves for filaments containing
stainless steel (316L), titanium alloy (Ti6Al4V), neodymium powder is most likely responsible for these differences.
alloy (NdFeB), strontium ferrite (SrFe12O19) and yttria stabilised In general, feedstocks with small particles have smaller
zirconia (YSZ) [11]. pores between the particles and a higher number of
contact points between those particles [13,14]. This cre-
As can be seen in Figure 1, the mechanical proper- ates an intricate network through which the dissolved
ties of the filaments are greatly affected by the powder polymers must be evacuated. In addition, the particles
used. For those filaments containing 316L powder a have a high tendency to agglomerate [15], which gener-
yield stress point followed by strain hardening could ates defects during the debinding and sintering steps.
be observed. The highest elongation at break (∼41%) Since zirconia is an important material for industrial
and maximum stress (∼12%) values were measured and dental applications, it was decided to make a more
for this material. Filaments with titanium have a detailed investigation on the solvent debinding behav-
shorter elongation at break (∼10%) and no maximum iour of zirconia-filled feedstocks. Three main variables
after the onset of plastic deformation. The curve for were investigated: (i) solvent debinding temperature,
neodymium alloy filaments has a much shorter (ii) addition of a surfactant (stearic acid) to the binder
elongation at break (∼3%) and the stress continuously system and (iii) the incorporation of a swelling inhibi-
decays after reaching a maximum. Finally, filaments tor (isopropanol) into the solvent to reduce defects.
containing ceramic powders (strontium ferrite and zir- The solvent temperature is a major parameter affect-
conia) have very low elongation at break with high ing solvent debinding. Three major phenomena occur
stress values, i.e. very brittle filaments were obtained during the debinding: the diffusion of the solvent into
for the feedstocks with these powders. Despite the big the organic components, the dissolution of the soluble
difference in the tensile properties, all filaments were binder and the diffusion of the dissolved polymers
processable by FFF with a Hage3D-140L FFF machine from the inner regions to the surface [16]. A tempera-
(Hage Sondermaschinenbau GmbH & Co KG, Obdach ture raise speeds up these phenomena and thus the
Austria). Examples of the printed parts are shown in overall debinding rate. Nevertheless, it could also result
Figure 2. in defects and dimensional changes [13].
A two-step debinding process combining solvent One reason for adding surfactants to the binder
and thermal debinding can be conducted for the devel- system is the increase of the dispersion of the filler par-
oped binder. Therefore the solvent debinding behav- ticles ensuring that individual particles are surrounded
iour of the feedstock materials was also investigated. by binder [17]. Also the surfactant will be removed
In Figure 3(a), the amount of soluble binder removed easily from the binder at the same time as the soluble

Figure 2. Examples of parts build by FFF with 5 powder types: stainless steel (316L), titanium alloy (Ti6Al4V), neodymium alloy
(NdFeB), strontium ferrite (SrFe12O19) and yttria stabilised zirconia (YSZ) [11].
198 C. KUKLA ET AL.

Figure 3. (a) Mass loss of soluble binder component for feedstocks with stainless steel (316L), titanium alloy (Ti6Al4V), neodymium
alloy (NdFeB), strontium ferrite (SrFe12O19) and yttria stabilised zirconia (YSZ); (b) specimens after debinding in cyclohexane at 60°C
at different times [11].

component, since it has a low melting point, leaving GmbH & Co.KG) at 180°C and 60 rev min–1. The com-
space for more binder to leave without damaging pounding started with the filling of the binder (includ-
the part. ing the SA in the compounds in which it was included),
To conduct the solvent debinding process, a non- followed by the powder, which was introduced in 5
polar binder is coupled with a non-polar solvent, times every 5 min. A total compounding time of
which in principle should ensure the dissolution of 90 min was employed. After compounding the feed-
the main binder component. However, the solvent stocks were granulated in a cutting mill having a
could also interact easily with the non-polar polyolefin sieve with square orifices of 2 mm.
employed as a backbone, producing its swelling [18]. Cylinders with a diameter of 8 mm and a length
One way to reduce swelling is the incorporation of a 10 mm were produced by compression moulding in
swelling inhibitor with higher polarity as observed by a vacuum press (P200 PV, Dr. Collin GmbH,
Fan et al [19]. According to these authors, a significant Ebersberg, Germany). This approach enables the
swelling reduction and defect occurrence is attained study of the solvent debinding behaviour of small
while reducing only slightly the debinding rate [19]. quantities of material on a fast and efficient way. In
Table 1 the compression moulding parameters can be
found. After the specimens were prepared their mass
Experimental procedure was recorded.
Tetragonal zirconia powder used to prepare feedstocks Cyclohexane (Carl Roth GmbH + Co, KG, Karls-
in this investigation was TZ-3YS-E grade supplied by ruhe, Germany) was the selected non-polar solvent
the Tosoh Corporation (Tokyo, Japan). The powder for the dissolution of the main binder component. Iso-
is supplied as spray dried granules with a primary par- propanol (Carl Roth GmbH + Co, KG, Karlsruhe,
ticle size of d50 = 0.6 µm and a BET (Brunauer– Germany) was used as a polar solvent and thus swelling
Emmett–Teller) specific surface area of 7 ± 2 m2 g–1. inhibitor. A fixed ratio of 20 mL of solvent per gram of
Feedstocks with a 50 vol.-% of powder fraction were feedstock was used. The solvent and specimens were
produced with two types of binders. The first binder placed in a desiccator DN100 and a recirculating oil
investigated consisted of a thermoplastic elastomer bath with heat controllers (Lauda Thermosthat, Delran
TPE (Kraiburg TPE GmbH & Co.KG, Waldkraiburg, NJ, USA) was employed to control the temperature. A
Germany) and a grafted polyolefin (Byk Chemie Dimroth condenser was attached to the desiccator lid
GmbH, Wesel, Germany). To investigate the influence in order to reflux the solvent and prevent its evapor-
of a surfactant, 5 vol.-% of the TPE was substituted by ation. The tests were conducted at temperatures of
stearic acid SA (Merck, KGaA, Darmstadt, Germany). 50, 60 and 70°C and times of 1, 3.5 and 6 h. Right
Feedstocks without and with SA will be denoted as after extraction from the solvent, the length of the
feedstock A and B, respectively.
Before compounding, the powder was pre-dried at
Table 1. Parameters employed for the production of
180°C for 12 h in order to remove the moisture and specimens by compression moulding.
reduce its tendency to agglomerate as it is known Stage 1 2 3
from the ceramic injection moulding process [15]. Time min 40 5 20
Then the material was compounded in an internal Temperature °C 175 175 30
Pressure bar 1 50 50
mixer Brabender Plasticorder PL 2000 (Brabender
 POWDER METALLURGY 199

parts was measured and later the specimens were dried Effect of the solvent debinding temperature
in a vacuum oven (Binder GmbH, Tuttlingen,
In Figure 4 the defects observed after the immersion
Germany) at 80°C for 1 h. The mass loss and defect
tests at different temperatures are shown. All the speci-
appearance were studied after the parts were dried.
mens had large cracks, independently of the solvent
Using the measured mass loss of the specimens, the
temperature. The cracks can be attributed to the binder
loss of soluble binder (lsb ) was estimated as shown in
softening and swelling, which occur during the solvent
Equation (1):
debinding process [20,21]. When the specimens are
mi − mf 1 immersed in the hot solvent, a sharp expansion is pro-
lsb = · · 100% (1)
mi wsb duced due to the heat [13]. Then the solvent penetrates
into the specimens and diffuses between the polymer
where mi is the initial mass of the specimen after
molecules, producing the swelling of the non-soluble
compression moulding, mf is the final mass of the
and soluble components. Once the dissolution of the
specimen after being in the solvent for either 1, 3.5 or
second group occurs, the solved products are evacuated
6 h and after drying for 1 h at 80°C and wsb is the
out of the specimens by capillary forces [13]. As the
mass fraction of soluble binder in the feedstock,
time progresses, a more soluble binder is extracted
which is confidential.
and the solvent penetrates further into the specimens,
causing the increase of the cracks size (Figure 4).
Results and discussion
In Figure 5(a) the loss of soluble binder at differ-
The loss of soluble binder, length change and appear- ent times and temperatures can be observed. The
ance of defects during debinding was investigated as increase in temperature clearly increases the debind-
function of: (i) the debinding temperature (ii) the ing rate. An increase in temperature not only pro-
addition of SA to the binder and (iii) the use of isopro- duces an increase in the solubility of the binder,
panol as swelling inhibitor. but also facilitates the diffusion of the solvent into

Figure 4. Defects observed in solvent debound specimens at different times and temperatures for feedstock A.
200 C. KUKLA ET AL.

Figure 5. (a) Loss of soluble binder and (b) length change over time at different temperatures for feedstock A.

the specimen and of the dissolved polymers out to diffusion rate of the dissolved TPE seems to reduce
the components [22]. Nevertheless, these results the dimensional variation.
must be evaluated together with the dimensional
variation and defects observed in the parts, since
Incorporation of SA into binder formulation
these values are also expected to increase with the
temperature increase [13]. In Figure 6, the defects observed in the feedstocks with-
The maximum length change values at the differ- out (Feedstock A) and with SA (Feedstock B) at differ-
ent evaluated conditions are plotted in Figure 5(b). A ent times and at 60°C can be observed. The
larger dimensional variation occurs when debinding incorporation of SA into the binder formulation
at a higher temperature at 1 h, but the opposite resulted in a reduction of the cracks size, especially at
trend occurs after 6 h. According to previous studies, longer debinding times. Nevertheless, it did not solve
a peak of swelling is observed due to the expansion the appearance of cracks. In order to quantify the
of the soluble components prior to their diffusion effect of the stearic acid incorporation, the loss of sol-
out of the specimen [13,23]. Observing Figure 5, it uble binder and the length change were determined
can be stated that the swelling peak is observed at for both feedstocks.
3.5 h for 70°C, not being observed for the other Figure 7(a) shows the loss of soluble binder for the
temperatures and times. In addition, the highest tested feedstocks at different times and at 60°C. The
swelling value at 6 h is obtained at 50°C, since a fraction of removed binder after the incorporation of
smaller amount of binder could be leached compared SA increases at all measured times. Two phenomena
to the other temperatures. The improvement of the might explain this improvement. First, the stearic

Figure 6. Defects observed in solvent debound specimens for feedstocks without (feedstock A) and with SA (feedstock B).
 POWDER METALLURGY 201

Figure 7. (a) Loss of soluble binder and (b) length change over time at 60°C for feedstocks without (feedstock A) and with SA (feed-
stock B).

acid has a lower molecular weight and a lower melting reduction in defects, since the reduced swelling caused
temperature than the thermoplastic elastomer in the by the solvent penetration into the specimen is also
binder, thus enhancing the dissolution and mobility homogeneous in the part.
of the dissolved polymer [24,25]. Additionally, the dis-
solution process might be facilitated by the improve-
Incorporation of isopropanol as swelling
ment in the dispersion of the powder, which has
inhibitor
been reported for ceramic oxide feedstocks containing
SA [26]. The length change of specimens was com- Figure 8 shows specimens after the immersion at differ-
pared to determine the influence of the surfactant in ent times in cyclohexane without and with 10 vol.-% of
the dimensional variation. It was observed that the isopropanol. No significant changes in the cracks could
use of SA clearly reduces the length of samples after be observed at any of the immersion times evaluated.
immersion in cyclohexane (Figure 7(b)), which results Therefore, the use of isopropanol as inhibitor could
in smaller defects (Figure 6). The small molecular not be considered as an effective solution for the
weight of SA not only improves the mobility and dis- large defects observed in the tested system.
solution, but results also in less swelling [24,25]. In Figure 9(a), the loss of soluble binder (lsb ) over
Additionally, the improvement of the powder dis- time for the different solvents is plotted. Only a small
persion in the specimens contributes to a further binder fraction (around 10% of binder) could be lea-
ched out of the specimens with isopropanol. For the
tests combining cyclohexane with 10 vol.-% of isopro-
panol no significant changes were observed compared
to those using only cyclohexane as solvent. The high
concentration of solvent per mass of part and the par-
tial solubility of some of the components of the ther-
moplastic elastomer in isopropanol might explain
why no difference was observed.
A different trend was observed by Fan et al. [19]
for paraffin wax Powder Injection Moulding (PIM)
feedstocks, where a clear reduction in the dissolved
fraction was measured when incorporating the swel-
ling inhibitors. The feedstock used in our investi-
gation contains a commercial TPE as soluble
Figure 8. Defects observed in solvent debound specimens component; commercial TPEs are multicomponent
after debinding in different solvents at 1, 3.5 and 6 h. compounds. As it can be observed in Figure 9, 10%
202 C. KUKLA ET AL.

Figure 9. (a) Mass loss of soluble binder and (b) length change over time in different solvents.

of the TPE is soluble in isopropanol, which might be attributed to the smaller particle size and the use of a
enough to compensate for the replacement of 10 vol.- binder with a large swelling. Despite the debinding
% of cyclohexane. Figure 9(b) shows the change in rate could be increased at high temperatures, the
length with time for different solvents at a tempera- large cracks observed in the specimens occurred at all
ture of 60°C. For pure isopropanol, a small length temperatures investigated. The incorporation of SA
change was measured. The immersion of the speci- to the binder in the melt mixing process could improve
men into a polar solvent results in a small dimen- the debinding rate and contribute to the reduction of
sional variation due to the poor interaction with defects, but it did not completely eliminate cracks.
the binder as observed in the mass loss values. Incor- Incorporating isopropanol as a swelling inhibitor has
porating 10 vol.-% of isopropanol only reduced the been also studied here, observing no significant
length change at short times. For the rest of the changes in the debinding rate and defects.
tested times, the incorporation of the second solvent For further reduction of the dimensional variation
did not have a significant effect reducing swelling and and defects, the modification of other parameters will
cracks still developed in all the specimens tested be studied in further steps. For instance, the improve-
(Figure 8). The partial solubility of the binder in iso- ment of the particle dispersion by using compounding
propanol can be the reason of the ineffectiveness of equipment with an increased shear and dispersive mix-
this substance as swelling inhibitor. Fan et al. [19] ing, such as co-rotating twin screw extruders and the
showed that alcohols could be used as swelling modification of the binder formulation to reduce swel-
inhibitors, while using substances that are able to ling and increase the debinding rate.
partially dissolve the binder had no significant
effect reducing swelling. In addition, paraffin wax
employed by Fan et al.[19] has a smaller molecular Disclosure statement
weight than TPE and thus less swelling is expected. No potential conflict of interest was reported by the authors.
This might explain the discrepancies observed here.

Funding
Conclusions and outlook This work was financially supported by the European Com-
mission for projects REProMag and CerAMfacturing under
A new binder system has been developed, which allows grant agreements 636881 and 678503, respectively.
processing of highly filled filaments by FFF with metal
and ceramic particles that later on can be solvent
debound and sintered for the production of metal Notes on contributors
and ceramic parts. Unlike its metallic counterparts, Christian Kukla is an expert in polymer engineering and the
feedstocks containing zirconia experience crack for- polymer-related processes in powder metallurgy MIM and
mation during solvent debinding [11]; this has been Additive Manufacturing-AM/Material Extrusion. He is
 POWDER METALLURGY 203

working in the field of MIM since 1995 and in the field of [2] Spoerk M, Gonzalez-Gutierrez J, Sapkota J, et al. Effect
AM since 2012. His current position is at the Industrial Liai- of the printing bed temperature on the adhesion of
son Department of the Montanuniversitaet Leoben, where he parts produced by fused filament fabrication. Plast,
is responsible for R&D projects together with the industry. Rubber Compos. 2018;47(1):17–24. DOI:10.1080/
Santiago Cano received the M. Sc. degree in Industrial 14658011.2017.1399531.
Engineering from the University of Castilla-La Mancha in [3] Gonzalez-Gutierrez J, Cano S, Schuschnigg S, et al.
2016. After the completion of his studies, he started working Additive manufacturing of metallic and ceramic com-
at the Institute of Polymer Processing of the Montanuniver- ponents by the material extrusion of highly-filled poly-
sitaet Leoben, where he is currently pursuing his PhD degree. mers: A review and future perspectives. Materials
His research interests include the production of ceramics (Basel). 2018;11(5), DOI:10.3390/ma11050840.
and metals by powder injection moulding and fused filament [4] Wu G, Langrana NA, Rangarajan S, et al. Fabrication
fabrication, with focus on the development of binder of metal components using FDMet: fused deposition
formulations. of metals. Solid Freeform Fabrication Symposium; 9–
11 August; Austin, Texas, 775–782.
Dario Kaylani received the B.Sc. degree in Polymer Engin- [5] Cruz N, Santos L, Vasco J, et al. Binder system for
eering and Science from theMontanuniversitaet Leoben in fused deposition of metals. Euro PM2013 Congress &
2017. Currently he is pursuing his M.Sc. degree at the Insti- Exhibition; 15–18 September; Gothenburg, Sweden.
tute of Polymer Processing of the Montanuniversitaet Leo- EPMA, 79–84.
ben. His research interests are the processing and [6] Agarwala MK, Jamalabad VR, Langrana NA, et al.
characterization of polymer composites, including feed- Danforth: ‘structural quality of parts processed by
stocks for powder injection moulding. fused deposition’. Rapid Prototyp J. 1996;2(4):4–19.
Stephan Schuschnigg received his M.Sc. Degree in polymer DOI:10.1108/13552549610732034.
engineering at the Montanuniversitaet Leoben. His PhD [7] McNulty TF, Mohammadi F, Bandyopadhyay A, et al.
deals with the solid conveying zone of single screw extruders. Development of a binder formulation for fused depo-
Currently he is the work group leader for Additive Manufac- sition of ceramics. Rapid Prototyp J. 1998;4(4):144–
turing and Extrusion at the Institute of Polymer Processing 150. DOI:10.1108/13552549810239012.
in the Department of Polymer Engineering and Science. [8] Pistor CM. Thermal properties of green parts for fused
His main research is material extrusion and the use of highly deposition of ceramics (FDC). Adv Eng Mater 2001;3
filled systems. (6):418–423. DOI:10.1002/1527-2648(200106)3:6<
418::AID-ADEM418 > 3.0.CO;2-Q.
Prof. Clemens Holzer received his PhD in Polymer Engineer-
[9] Agarwala MK, van Weeren R, Bandyopadhyay A, et al.
ing and Science at Montanuniversitaet Leoben. After seven
Filament feed materials for fused deposition processing
years in the industry at Huber+Suhner, Switzerland as
of ceramics and metals’. solid Freeform fabrication
research engineer, head of production and finally head of
Symposium. Austin (TX): University of Texas.
research and development in a business unit he was deputy
[10] Gonzalez-Gutierrez J, Godec D, Kukla C, et al.
head of the Institute of Polymer Nanotechnology INKA
Shaping, debinding and sintering of steel components
and associate professor at FHNW, Switzerland. Since 2009
via fused filament fabrication. 16th International
head of Polymer Processing at the Department of Polymer
Scientific Conference on Production Engineering; 8 –
Engineering and Science and full professor at Montanuniver-
10 June; Zadar, Croatia. Croatian Association of
sitaet Leoben. His main research themes are injection
Production Engineering, 99–104.
moulding, extrusion, compounding, recycling, additive man-
[11] Kukla C, Gonzalez-Gutierrez J, Cano S, et al. Fused
ufacturing, simulation and determination of material data.
filament fabrication (FFF) of PIM feedstocks. VI
Joamin Gonzalez-Gutierrez received the PhD degree in Congreso Nacional de Pulvimetalurgia y I Congreso
Mechanical Engineering from the University of Ljubljana, Iberoamericano de Pulvimetalurgia; Ciudad Real,
Slovenia in 2014. Currently he is a postdoctoral researcher Castilla La Mancha, Spain. Comité Español de
at the Institute of Polymer Processing, Montauniversitaet Pulvimetalurgia, 1–6.
Leoben, Austria. His research interest includes powder injec- [12] Gonzalez-Gutierrez J, Duretek I, Holzer C, et al. Filler
tion moulding, additive manufacturing, and development content and properties of highly filled filaments for
and characterisation of highly filled polymeric systems. fused filament fabrication of magnets. ANTEC,
Anaheim, CA, USA, 8–10 May. Society of Plastics
Engineers, 1–4.
ORCID [13] Westcot EJ, Binet Andrandall C, German RM. In situ
Christian Kukla http://orcid.org/0000-0002-2233-009X dimensional change, mass loss and mechanisms for
Santiago Cano http://orcid.org/0000-0001-6361-6185 solvent debinding of powder injection moulded com-
Stephan Schuschnigg http://orcid.org/0000-0002-2601- ponents. Powder Metall. 2003;46(1):61–67. DOI:10.
967X 1179/003258903225010442.
Clemens Holzer http://orcid.org/0000-0001-5149-7895 [14] Contreras JM, Jiménez-Morales A, Torralba JM.
Joamin Gonzalez-Gutierrez http://orcid.org/0000-0003- Fabrication of bronze components by metal injection
4737-9823 moulding using powders with different particle charac-
teristics. J Mater Process Technol. 2009;209(15–
16):5618–5625. DOI:10.1016/j.jmatprotec.2009.05.021.
[15] Mutsuddy BC, Ford RG. Ceramic injection moulding.
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