Espirales. Revista multidisciplinaria de investigación científica, Vol. 8, No. 51
October - December 2024 e-ISSN 2550-6862. pp 51-66
DOI https://doi.org/10.31876/er.v8i50.875
Elasticity and plasticity of PLA, PETG, ABS polymers for
printing automotive parts
Elasticidad y plasticidad de los polímeros PLA, PETG y ABS para la
impresión de piezas de automoción
Daniela Estefanía Cuenca Pérez*
Ember Geovanny Zumba Novay*
Holger Patricio Castillo Mazón*
Jean Pierre Quinchuela Llamuca*
Received: May 18, 2024
Approved: September 28, 2024
Abstract
The objective of this paper is to explore the elasticity and plasticity
properties of PLA, PETG and ABS polymers in the context of 3D
printing of automotive parts. The present research is qualitative,
descriptive, focusing on the theoretical analysis of the mechanical
properties of PLA, PETG and ABS polymers, which is based on the
collection of information from different authors. An analysis of the
properties of these polymers is very significant for their application in
the automotive industry, allowing a correct selection of materials. The
research found very important data, highlighting that PLA, with its
high stiffness and low plasticity, is ideal for prototypes and low-stress
parts, while PETG offers a balance between flexibility and strength,
suitable for functional components that require durability. ABS,
known for its high impact strength and ductility, is recommended for
applications that demand shock absorption and durability under
demanding conditions. Selecting the right material is crucial to
optimize the performance and longevity of 3D printed automotive
parts, contributing to the advancement of additive manufacturing
technology in the industry.
Keywords:
Elasticity, Plasticity, 3D Printing, Automotive parts.
* Ingeniera Química, Alicante, España. Docente Escuela
Superior Politécnica de Chimborazo – ESPOCH,
aleinad_cuenca@hotmail.com, https://orcid.org/0009-
0008-9446-8187
* Magister en Diseño Industrial y de Procesos - Magister en
Educación Tecnología e Innovación, Docente Escuela
Superior Politécnica de Chimborazo – ESPOCH, Riobamba,
Ecuador. ezumba@espoch.edu.ec, https://orcid.org/0000-
0002-2121-8418
* Magister en Pedagogía del Inglés como Lengua
Extranjera, Docente Escuela Superior Politécnica de
Chimborazo – ESPOCH, Riobamba, Ecuador.
holger.castillo@espoch.edu.ec,
https://orcid.org/0000-0002-6853-6341
* Ingeniero Mecánico. Ingeniero en Refrigeración Industrial,
Docente Escuela Superior Politécnica de Chimborazo –
ESPOCH, Riobamba, Ecuador, jean.quinchuela@epn.edu.ec
https://orcid.org/0009-0001-9222-3484
Cuenca, D., Zumba, E., Castillo, H.,
Quinchuela, J. (2024) Elasticity and
plasticity of pla, petg, abs polymers
for printing automotive parts.
Espirales Revista Multidisciplinaria
de investigación científica, 8 (51),
51- 66
Elasticity and plasticity of PLA, PETG, ABS polymers for printing automotive parts
Espirales. Revista multidisciplinaria de investigación científica, Vol. 8, No. 51
October - December 2024 e-ISSN 2550-6862. pp 51-66
52
Introduction
The word polymer literally means “many parts”. In this sense, a solid polymeric material
can be considered one that contains multiple chemically linked parts or units that are
joined together to form a solid. Plastics are divided into two classes, thermoplastics and
thermosets. (Hashemi, 2006)
According to studies carried out by Callister (2014) polymers include the well-known
plastic and rubber materials. Many of them are organic compounds chemically based
on carbon, hydrogen and other non-metallic elements. They have very large molecular
structures, often in the form of a chain, which usually have a backbone of carbon atoms.
While Askeland (2016) considers thermoplastics to be a special group of polymers in
which the molecular chains are entangled, but not interconnected. They can be easily
melted and formed into useful shapes. Generally, these polymers have a structure like
that of a chain.
A wide range of thermoplastic filaments such as PLA, ABS, and PETG are used in 3D
printing. Disposing of these in landfills or burning them is an ill-advised idea as they
have negative repercussions on the environment. Processing the materials before they
can be reused also requires energy and this adds to the impact that the respective
Resumen
El objetivo de este trabajo es explorar las propiedades de elasticidad
y plasticidad de los polímeros PLA, PETG y ABS en el contexto de la
impresión 3D de piezas de automoción. La presente investigación es
cualitativa, descriptiva, centrada en el análisis teórico de las
propiedades mecánicas de los polímeros PLA, PETG y ABS, que se
basa en la recopilación de información de diferentes autores. El
análisis de las propiedades de estos polímeros es muy significativo
para su aplicación en la industria automovilística, permitiendo una
correcta selección de los materiales. La investigación encontró datos
muy importantes, destacando que el PLA, con su alta rigidez y baja
plasticidad, es ideal para prototipos y piezas de bajo estrés, mientras
que el PETG ofrece un equilibrio entre flexibilidad y resistencia,
adecuado para componentes funcionales que requieren durabilidad.
El ABS, conocido por su gran resistencia al impacto y ductilidad, se
recomienda para aplicaciones que exigen absorción de impactos y
durabilidad en condiciones exigentes. Seleccionar el material
adecuado es crucial para optimizar el rendimiento y la longevidad de
las piezas de automoción impresas en 3D, contribuyendo al avance
de la tecnología de fabricación aditiva en la industria.
Palabras clave:
Elasticidad, Plasticidad, Impresión 3D, Piezas de
automoción.
Daniela Estefanía Cuenca Pérez, Ember Geovanny Zumba Novay, Holger Patricio Castillo Mazón, Jean Pierre
Quinchuela Llamuca
Espirales. Revista multidisciplinaria de investigación científica, Vol. 8, No. 51
October - December 2024 e-ISSN 2550-6862. pp 51-66
53
materials have on the environment. Therefore, the choice of filament type plays an
important role in the circular economy of filaments. Kumar (2022).
Materials and methods
A literature study was conducted on the mechanical properties of PLA, PETG and ABS
polymers. The values of tensile strength, modulus of elasticity and elongation at break
of each material were investigated. Concepts of 3D printing, elasticity and plasticity
were reviewed using official sources obtained from the library of the Faculty of
Mechanics as well as digital sources such as Google Scholar, Scopus and Microsoft
Academic. Having reviewed 30 articles, 1 documentary, 5 books, 14 videos which
contained information in accordance with the present research, 3 books and 30 articles
were selected.
In classical mechanics, “plasticity” describes the deformation induced by an external
stress that remains permanent after the stress is removed. “Elasticity” describes the
fdeformation that is reversed when the stress is released. Therefore, plasticity and
elasticity refer to clearly different stress response behaviors of the material. Colombi
(2024).
The two parameters that determine the elasticity of a material are its elastic modulus
and its yield strength. A high elastic modulus is typical of materials that are difficult to
deform; that is, materials that require a high load to achieve significant tension. An
example is a steel strip. A low elastic modulus is typical of materials that deform easily
under load; for example, a rubber band Mechatronics (2020).
Each material has its own characteristic stress-strain curve.
Figure 1.
Stress-Tension Diagram
Source: Mechatronics (2020)
A typical stress-strain diagram for a ductile metal subjected to a load. In this figure, the
stress is a fractional elongation (not drawn to scale). As the load is gradually increased,
Elasticity and plasticity of PLA, PETG, ABS polymers for printing automotive parts
Espirales. Revista multidisciplinaria de investigación científica, Vol. 8, No. 51
October - December 2024 e-ISSN 2550-6862. pp 51-66
54
the linear behavior (red line) that begins at the unloaded point (the origin) ends at the
limit of linearity at point H. For further load increments beyond point H, the stress-strain
relationship is nonlinear, although still elastic. In the figure, this nonlinear region is seen
between points H and E. Increasingly increasing loads drive the stress to the yield point
E, where elastic behavior ends and plastic deformation begins. Beyond the yield point,
when the load is removed, for example at P, the material relaxes to a new shape and
size along the green line. That is, the material is permanently deformed and does not
return to its initial shape and size when the stress is removed. Jesus, (2018).
Figure 2.
Stress and strain diagram
Source: Zumba (2024)
Importance in 3D Printing
In 3D printing, especially for automotive applications, elasticity and plasticity properties
are crucial for several reasons: Antolín, (2012)
Elasticity in Automotive Parts.
Shock Absorption: Components that may suffer impacts or vibrations (such as engine
mounts) need elastic materials that can absorb and dissipate energy, reducing damage
to other parts. Askeland, (2016)
Shape Recovery: Parts such as gaskets and seals need to recover their original shape
after deformation to ensure proper sealing and continued operation. Jesus, (2018)
Plasticity in Automotive Parts.
Formability: Some components require forming or adjusting after printing. The ability
of a material to be molded without fracturing is essential. Askeland, (2016)
Resistance to Permanent Deformations: In situations where parts are subject to
continuous loads or high temperatures, high plasticity ensures that parts do not fracture
under extreme stress, maintaining structural integrity. Romero, (2023).
Daniela Estefanía Cuenca Pérez, Ember Geovanny Zumba Novay, Holger Patricio Castillo Mazón, Jean Pierre
Quinchuela Llamuca
Espirales. Revista multidisciplinaria de investigación científica, Vol. 8, No. 51
October - December 2024 e-ISSN 2550-6862. pp 51-66
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Examples of Applications in Automotive 3D Printing:
Brackets and Mounts: They need elasticity to absorb vibrations and shocks without
breaking. Kumar, (2022)
Interior Components: Plastics with good plasticity to mold complex shapes and fit the
interior contours of the car. Callister, (2014)
Prototypes and Custom Parts: The ability to adjust 3D printed parts for a perfect fit is
vital, requiring both elasticity and plasticity. Askeland, (2016)
The right combination of elasticity and plasticity in 3D printed materials is essential to
ensure parts function properly under the dynamic and varied conditions found in
automotive applications. Antolín, (2012)
Analysis of PLA (Polylactic Acid)
Figure 3.
PLA
Source: Antolin Group.
Elasticity and Plasticity of PLA
Elasticity
Behavior under stress: PLA has limited elasticity and tends to be more brittle compared
to other polymers. Its elastic modulus is relatively high, meaning it is stiff and does not
deform easily under moderate stresses. Kumar, (2022)
Recovery: It does not recover well from plastic deformations, as it tends to break rather
than permanently deform. Rodriguez, (2023).
Plasticity:
Permanent deformation: PLA has low plasticity. Once its elastic limit is exceeded, it is
more prone to fracture than to permanently deform. Callister, (2014)
Ductility: PLA's ductility is limited, making it less suitable for applications that require
considerable deformation without fracture. Rodriguez, (2023).
Elasticity and plasticity of PLA, PETG, ABS polymers for printing automotive parts
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Advantages and Limitations of PLA in Automotive Applications
Advantages:
Biodegradability: PLA is biodegradable and compostable under industrial conditions,
which is a significant environmental benefit. Kumar, (2014).
Ease of printing: It prints well at low temperatures and does not require a heated bed,
reducing the cost and complexity of printing. Antolín, (2022).
Limitations:
Thermal resistance: PLA has a low thermal resistance (up to about 60°C), which limits its
use in components exposed to high temperatures. Rodríguez, (2023).
Fragility: Its low elasticity and plasticity make it more prone to fracture under mechanical
loads and shocks, limiting its use in structural parts or those subjected to significant
stresses. Rodríguez, (2023).
Figure 4.
Auto parts
Source: Antolin Group.
Figure 5.
PETG
Analysis of PETG (Polyethylene Terephthalate Glycol)
Source: Antolin Group.
Daniela Estefanía Cuenca Pérez, Ember Geovanny Zumba Novay, Holger Patricio Castillo Mazón, Jean Pierre
Quinchuela Llamuca
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Elasticity and Plasticity of PETG
Elasticity:
Behavior under stress: PETG has good elasticity, allowing it to withstand moderate
deformations and recover its original shape without fracturing. Hasemi, (2006).
Recovery: It has excellent elastic recovery, making it suitable for applications requiring
flexibility. Hasemi, (2006).
Plasticity:
Permanent deformation: PETG can be plastically deformed without breaking, which
gives it good ductility. Hasemi, (2006).
Ductility: It is more ductile than PLA, allowing greater deformation before reaching the
fracture point. Rodríguez, (2023).
Advantages and Limitations of PETG in Automotive Applications
Advantages
Impact resistance: It has a high impact resistance, making it ideal for parts that require
durability. Bozzelli, (2021).
Thermal stability: It has better thermal resistance than PLA (up to about 75-80°C),
allowing it to be used in more demanding environments. Rodríguez, (2023).
Chemical resistance: It offers good resistance to acids and alkalis, which is beneficial in
automotive applications. Antolín, (2022).
Limitations
Biodegradability: It is not biodegradable like PLA, which can be a disadvantage from an
environmental point of view. Kumar, (2022)
Cost: It can be more expensive than PLA, which can be a limiting factor in low-cost
applications. Rodríguez, (2023).
Elasticity and plasticity of PLA, PETG, ABS polymers for printing automotive parts
Espirales. Revista multidisciplinaria de investigación científica, Vol. 8, No. 51
October - December 2024 e-ISSN 2550-6862. pp 51-66
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Figure 6.
Gears
Source: Antolin Group
Analysis of ABS (Acrylonitrile Butadiene Styrene)
Elasticity and Plasticity of ABS
Figure 7
. ABS
Source: Antolin Group.
Elasticity
Behavior under stress: ABS has good elasticity and can absorb shocks and vibrations
without fracturing. Bozzelli, (2021).
Recovery: It recovers its shape well after elastic deformations, making it suitable for
applications requiring resilience. Bozzelli, (2021).
Plasticity
Permanent deformation: ABS has high plasticity, allowing significant permanent
deformations before fracturing. Antolín, (2022).
Ductility: It is highly ductile, allowing it to be molded and adjusted without risk of
breakage. Kumar, (2022)