Base-isolation is a well-known technique used in earthquake-resistant structures and isolation devices sustainably preserve the entire structure by reducing earthquake energy transmitted to the structure. Lead Rubber Bearings (LRBs) are the most widely used devices as base-isolators, because of their seismic performance, stability, and being economical. LRBs are essential for structural sustainability, but they also have some characteristics that should be considered to improve sustainability. People are likely to be exposed to various forms of lead material, which is highly toxic and used extensively in LRBs, not only when it is damaged or needs replacement after major earthquakes, but also at each stage of lead's entire life cycle, from production to recycling. Due to the toxic properties of lead, which is also used in various parts of the structures, it is often possible to obtain outcomes equivalent to the results expected from the use of lead material with the use of alternatives, while the situation is quite different for the use of alternatives in LRBs. The necessity of alternative materials to provide various mechanical properties by complying with certain limits complicates the search for alternative materials. In addition, the seismic isolator system must be examined in detail, since the damping performance of alternative materials together with other materials in the composite structure of LRBs does not depend only on the mechanical properties of the alternative core material. It is important to consider not only the mechanical properties of alternative materials, but also the state of toxicity which is one of the properties to be avoided, thermal properties, and even recrystallization, which is often overlooked. The recrystallization property of lead, which starts at values lower than room temperature for lead, which increases its ductility, is one of the properties that make it difficult to find an alternative to lead. In this study, the properties of lead material were accepted as the lower limit for the mechanical properties of alternative core materials. On the other hand, it is necessary to have an upper limit for the mechanical properties of alternative materials in order not to damage the other components that make up the isolator, and in this context, to protect the structural form and stability of the isolator. For this reason, in addition to the results obtained from the performance analysis, plastic deformation-related outputs of the steel shims are also presented with additional evaluations.

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International İstanbul Scientific Research Congress - July 23-25, 2022
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SEISMIC PERFORMANCE PREDICTIONS of
CANDIDATE YIELDING METALS and METAL ALLOYS
INSTEAD of LEAD for LRBs
Gokhan Altintas
Manisa Celal Bayar University, Engineering Faculty, Civil Engineering Department, Manisa, Turkey
ORCID: 0000-0003-2334-7704
ABSTRACT
Base-isolation is a well-known technique used in earthquake-resistant structures and isolation devices
sustainably preserve the entire structure by reducing earthquake energy transmitted to the structure.
Lead Rubber Bearings (LRBs) are the most widely used devices as base-isolators, because of their
seismic performance, stability, and being economical. LRBs are essential for structural sustainability,
but they also have some characteristics that should be considered to improve sustainability. People
are likely to be exposed to various forms of lead material, which is highly toxic and used extensively
in LRBs, not only when it is damaged or needs replacement after major earthquakes, but also at each
stage of lead’s entire life cycle, from production to recycling. Due to the toxic properties of lead, which
is also used in various parts of the structures, it is often possible to obtain outcomes equivalent to the
results expected from the use of lead material with the use of alternatives, while the situation is quite
different for the use of alternatives in LRBs. The necessity of alternative materials to provide various
mechanical properties by complying with certain limits complicates the search for alternative materials.
In addition, the seismic isolator system must be examined in detail, since the damping performance of
alternative materials together with other materials in the composite structure of LRBs does not depend
only on the mechanical properties of the alternative core material. It is important to consider not only
the mechanical properties of alternative materials, but also the state of toxicity which is one of the
properties to be avoided, thermal properties, and even recrystallization, which is often overlooked. The
recrystallization property of lead, which starts at values lower than room temperature for lead, which
increases its ductility, is one of the properties that make it difficult to find an alternative to lead. In this
study, the properties of lead material were accepted as the lower limit for the mechanical properties of
alternative core materials. On the other hand, it is necessary to have an upper limit for the mechanical
properties of alternative materials in order not to damage the other components that make up the isolator,
and in this context, to protect the structural form and stability of the isolator. For this reason, in addition
to the results obtained from the performance analysis, plastic deformation-related outputs of the steel
shims are also presented with additional evaluations.
Keywords: Lead rubber bearing, toxicity, eco-friendly design, material selection, recrystallization,
lead

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INTRODUCTION
The properties that are primarily considered in structural materials are mainly the physical,
mechanical, and thermal properties. In order to maintain the performance of these properties throughout
the economic life, parameters belonging to the concepts of reliability and durability are presented
together with the materials and are taken into account in the material selection.
On the other hand, due to the increasing sensitivity about public health and environmental issues, the
determination to put forward the most eco-friendly approaches in an evaluation process that includes
all stages of the life cycle of materials as well as physical, mechanical, and thermal properties in the
selection of materials to be used in buildings is more important than ever. Reducing the use of toxic
materials in structures is important for sustainability [1, 2], and in this context, one of the most important
options in the list of things to do in reducing the use of toxic materials is to search for clean alternatives
of toxic materials [3, 4, 5]. The lead material, which is sought as an alternative in this study, is a metal
with well-known toxic properties [6] and has a high potential to increase undesirable environmental
effects due to the increasing use of LRBs. The neurotoxicity effects of lead are particularly dangerous
for the fetus, infant, and adolescent [7-12]. These effects are also dangerous for adults who are exposed
to various forms of lead [13-15]. Many regulations and safety warnings must be complied with in works
that require the use of lead, since lead is a metal that requires great care not only when it is used as a
structural material, but also throughout all stages of its entire life cycle [16-22]. However, this is not the
case, for non-regulated countries especially in the field of recycling, and as a result of intensive informal
recycling practices, they cause major problems both in human health and in the environment [23]. Due
to the toxic properties of lead arising from its natural structure, there are many studies in the literature
on the search for alternative materials in various fields where lead is used in order to avoid the contact of
any form with humans, especially in order to avoid the use of lead or to switch to situations where lead
is used in lesser amounts [24-31].
Although LRBs bulk up in a large amount of lead, they play a very important role in terms of structural
sustainability. In addition to providing life safety, LRBs have an increasing importance day by day due to
their role in preventing economic losses owing to the fact that the structure survives even major earthquakes
without damage. The importance of this situation in terms of sustainability is the protective effect of seismic
isolators not only for the materials that make up the structural systems, but also for the prevention of the
uncontrolled spread of all kinds of non-structural materials inside the buildings as a result of destruction.
From a broader point of view, the effect of the emergence of new carbon footprints that will arise due to the
reproduction of a destroyed structure and its contents, and the prevention of the start of new cycles in the
life-cycles of the materials to be used for new productions is very important.
A comprehensive study is required in order to accept the results of the research on the production
of seismic isolators with sustainable materials. Because, while it is possible to reach a conclusion by
evaluating one or more of the properties of the material in many cases in search of alternative materials
in various fields, the effects of the alternative core materials examined in this study on the seismic
performance of the isolators and other materials that make up the isolator need to be revealed through
detailed analysis.
In this context, based on a benchmark model [32], performance analyzes of seismic isolator models
with alternative core materials were made and additionally the plastic deformation results of the
components due to the interaction of different materials, which are important in terms of structural
integrity and stability, were also evaluated.
LRB MODEL and MODEL VERIFICATION
The LRB based on the analysis made within the scope of this study is the Skellerup 150 [32] isolator
manufactured by Skellerup Industries. In order for the isolator to be used appropriately in the simulations

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and to obtain realistic results, validation and calibrations of the numerical model to be created must be
done. To verify the numerical model, the numerical results are compared with the experimental results
provided by the manufacturer. The cyclic loading tests are an essential part of the procedure in the design
of the base isolators. Using the precise simulations of hysteresis tests and knowing the limitations of
the finite element (FE) models as numerical models, it is possible to design seismic isolators based on
experiments properly. Geometrical properties of Skellerup 150 are presented in Table 1.
Table 1 Geometrical properties of Skellerup 150 LRB.
Part Name Diameter (mm) Thickness / Height*
(mm)
Number of parts
Loading Plates 601 31.8 2
Fixing Plates 431 25.4 2
Rubber Layers 431 9.5 11
Steel Shims 431 3 10
Lead Core 116.8 185* 1
In order to make the structural form more understandable, the 3D rendered model of Skellerup
150 LRB was created as in Fig. 1, based on the schematic drawings of the manufacturer [32] and the
geometric dimensions provided by the manufacturer, which are presented in Table 1.
Fig. 1. Skellerup 150 lead rubber bearing.
Before mentioning the material properties, it will be useful to look at the FE model created for
this study. In the created FE model, special attention was paid to the nodal compatibility on the lines
with material transitions and the compatibility of the surface correspondences for different material
interaction surfaces. The optimum mesh obtained by mesh density analysis was created from 59200
linear 8 node hexahedral elements as shown in Fig. 2. 17472 of these elements have hybrid formulations
for hyperelastic rubber modeling.

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Fig. 2. FE model views of LRB; (a) FE model view with cutout section, (b) FE model view without top and
bottom steel parts.
The properties of the materials used in LRB are presented in Table 2. In all analyzes performed
in this study, steel and rubber properties were the same as presented in Table 2, and the properties of
core materials were modeled as trilinear. Although the properties of the lead material used in model
validation are close to those in the publications using the benchmark isolator [33, 34], the additional
information required to use it in trilinear form has been created by using the results obtained from
various experiments for the lead [35, 36, 37].
Table 2 Mechanical properties of the materials used in LRB.
Steel Properties [34, 38]
Young’s Modulus 210000 MPa
Yield Stress 240 MPa
Poisson’s Ratio 0.3
Rubber Properties (Arruda-Boyce) [34]
Coefficients of the strain energy functions
C10 0.569053
C01 3.039270
Lead Properties
Yield Stress 6.5 MPa
Tensile Strength 21.8 MPa
Young’s Modulus 17000 MPa
In order for the created FE model to be used in the analyzes, it is of great importance that the results
of the FE model are compatible with the experimental data. In this context, in the numerical analysis
performed using the FE model with the optimized mesh, 667 kN loading in the vertical direction and
cyclic horizontal displacement with an amplitude of ±0.1524 m were applied to the FE model.

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-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-30000
-20000
-10000
0
10000
20000
30000
Force
(N)
Data from manufacturer [32-34]
Doudoumis et al. [33]
This study
Fig. 3. Closed envelope curves based on the second cycle.
Force-displacement envelopes obtained from the manufacturer’s experiment [32], Duodoumis et. al.
[33], and analysis performed in this study are presented in Fig. 3. As can be seen, the envelope curve of
the model created within the scope of the study verifies both the maximum and minimum force values
exactly and stays within the other envelopes.
Although different ways can be followed in the creation of envelopes, the envelope of the second
cycle can be used because the instability seen in cyclic curves almost completely decreases in the
second cycle, in the cases where the yield stress or ultimate tensile strength is exceeded in the first
cycle, especially in systems that are forced up to the limit values. The same approach was used in this
study.
Fig. 4. Lead core Von-Mises stress distribution; (a) at the end of the first quarter, (b) at the end of 5th
quarter.
Considering that each cycle consists of 4 quarters in the displacement domain, it is seen that the
distribution of Von-Mises stresses becomes more stable in the 5th quarter (first quarter of the second
cycle), although the lead core yields almost completely at the end of the first quarter. Due to the large
displacement value used in the experiment conducted by the manufacturer, the stress values of core

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material almost reach the last part of the trilinear curve of material behavior, starting from the ultimate
strength value, in the first quarter, so it is obvious that the determining stress values for the envelopes or
cyclic curves in this study will be ultimate tensile strength values of core materials.
ALTERNATIVE MATERIALS and PERFORMANCE PREDICTIONS
In LRB type seismic dampers, there are many evaluation criteria that an alternative core material
to be proposed instead of lead core material should meet [4, 39]. In this study, materials from a large
commercially defined metal and metal alloy pool were used due to the nature of the study for the
materials evaluated in terms of sustainability. Before starting the evaluations within the scope of the
analysis, as well as the mechanical, physical and some other properties of the materials, a large metal and
alloy pool was excluded from the evaluation due to the preselection criteria of the candidate materials
as shown in Fig. 5. To give a brief detail, since it is obvious that rare, inaccessible, and precious metals
will not be an option for such production, a very large set of alloys with related metals are not options
that can be used for core metal production. In the materials to be used as cores, criteria such as keeping
the residual stresses at the lowest level after the production phase, producing homogeneous and isotropic
cores, and the ability to cast and process metals and alloys without any problems were also used in the
preliminary evaluation stages.
Fig. 5. Material selection.
Due to the use of the mechanical properties of the materials in the analyzes, some limitations have
been placed on the mechanical properties to be used for the core material. In this context, two important
criteria were determined in the limitations of mechanical properties, the first of these criteria was decisive
in the creation of the lower limit and the second one in the creation of the upper limit. As the minimum
values of the mechanical properties, the properties of the lead material compiled from various sources
were accepted as the approximate lower limit [32-38, 40-47]. In terms of mechanical performance,
the use of soft materials, or in other words, Young’s modulus, yield, and ultimate strength values far
below those of lead, is avoided. It is clear that the use of a softer metal or alloy than lead will reduce the

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capacity of the seismic isolator. On the other hand, there is a risk that the use of harder materials without
a certain upper limit may jeopardize the integrity and stability of the isolator. Although it is thought that
not setting an upper limit on hardness and strength will not cause any problems in terms of stability at
first glance, steel shims, which are one of the most important elements of the isolator in terms of stability
and bearing, can be damaged due to an excessively hard core. In this context, attention was paid to
ensure that the highest Young’s modulus and strength values to be used are below that of steel shims in
order not to damage the steel shims during exposure to seismic loads. However, it is still possible that,
due to the shape and rigidity properties, in a system in motion, materials that are even softer than thin
steel shims can cause plastic deformation in steel shims. For this reason, plastic deformation results in
steel shims were included in the evaluation criteria in the analysis results.
Table 3 Limitations of material properties
Property Minimum Maximum
Young’s Modulus (Pa) 13e9 2e11
Yield Strength (Pa) 6e6 2.15e8
Tensile Strength (Pa) 15e6 2.5e8
In addition to the material limits presented in Table 3, the strain limit of the lead material was chosen
as the lower limit of the core’s strain limit [32-38, 40-47]. Representative materials to be used in the
analyzes in accordance with the mechanical limitations presented above and in accordance with other
evaluation criteria are presented in Table 4.
Table 4 Alternative core material properties [5, 36, 40-47].
Full Name UNS
number or
Designation
Young’s
Modulus
(N/mm2
)
Yield
Strength
(N/mm2
)
Tensile
Strength
(N/mm2
)
Poisson’s
Ratio
Aluminum, commercial purity A01501 7.05E+04 3.00E+01 8.00E+01 0.34
Lead-calcium alloy, cast, tin-free Pb-0.07Ca 1.50E+04 3.00E+01 3.75E+01 0.44
Zinc, commercial purity, Prime western Z19001 100000 120 150 0.25
Zinc, commercial purity, Special high grade Z13001 100000 120 135 0.25
Tin-antimony alloy, White Metal sn92sb8 5.25E+04 30 53 0.35
Brass, CuZn15As0.2, C23000 C23000 1.00E+05 9.50E+01 1.80E+02 0.345
Brass, CuZn35Sn1, C85700 C85700 9.60E+04 9.00E+01 2.80E+02 0.345
In here, tin-antimony alloy [48, 49], which is one of the alloys used in the analysis, has some toxic
properties, although not as much as lead, should be considered in the final evaluations. It should be
known that C23000 contains around 0.05% to 0.2% arsenic, although it is not considered toxic as a
component in the alloy. While the contents of some materials are different from each other, materials
such as lead-tellurium (L51123), whose mechanical properties are not much different from pure lead, are
not included in the analysis. In addition, the lead-tellurium (L51123) alloy contains the toxic properties
of both lead and tellurium [50]. On the other hand, even though it contains 99.9% lead, lead-calcium
alloy is included in the analyzes due to its higher mechanical properties than pure lead material. Because
of the mechanical properties, it is obvious that the performance that will be demonstrated in the use of
pure lead can be achieved with the use of less lead in case of using lead-calcium.

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ANALYSES and RESULTS
The geometric and material properties of Skellerup 150, which is the LRB type seismic damper used
in the evaluations, are the same as those in the verification section, and the analyzes were made again
for the same loading conditions with alternative core materials shown in Table 4.
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-2400000
-2000000
-1600000
-1200000
-800000
-400000
0
400000
800000
1200000
1600000
2000000
Force
(N)
C85700
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-1600000
-1200000
-800000
-400000
0
400000
800000
1200000
1600000
Force
(N)
C23000
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-1200000
-800000
-400000
0
400000
800000
1200000
Force
(N)
Z19001
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-1000000
-800000
-600000
-400000
-200000
0
200000
400000
600000
800000
1000000
Force
(mm)
Z13001
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-800000
-600000
-400000
-200000
0
200000
400000
600000
800000
Force
(N)
A01501
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-500000
-400000
-300000
-200000
-100000
0
100000
200000
300000
400000
500000
Force
(N)
Tin-Antimony Alloy
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-400000
-300000
-200000
-100000
0
100000
200000
300000
400000
Force
(N)
Lead Calcium (Pb-0.07Ca)
-160 -120 -80 -40 0 40 80 120 160
Displacement (mm)
-2400000
-2000000
-1600000
-1200000
-800000
-400000
0
400000
800000
1200000
1600000
2000000
Force
(N)
C85700
C23000
Z19001
Z13001
Tin-Antimony
Lead Calcium
A01501
Lead
Fig. 6. Force-displacement diagrams of the bearing models for the various core materials.

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Force-displacement loops of seismic isolators with alternative core materials are presented in Fig.
6. The presented performance curves are placed according to the horizontal force values of the seismic
isolators that occur at the largest displacement values used in the analysis. The hysteresis loops of the
investigated materials exhibit a very stable behavior, and the horizontal reaction forces were found to be
the same in absolute value at the largest displacement values of the isolator in both opposite directions.
All other core materials except C85700 and C23000 yielded completely in the first quarter, while C85700
and C23000 completely yielded before the second cycle started. At the maximum displacement of the
isolator at the end of the 7th quarter, the smallest horizontal force value was found to be 252.6 kN for the
lead, and the largest horizontal force value was found to be 1765.3 kN for the brass C85700. All of the
core materials not only yielded but also reached the ultimate tensile strengths. For this reason, the order
of the hysteresis loops presented according to the greatest horizontal force values is naturally the same
as the ordering of the core materials according to the ultimate tensile strengths. In the last graphic of Fig.
6, the force-displacement curves of the materials are presented together so that the examined materials
can be compared with each other more easily. Comparisons of the comments made about the ordering of
the curves and some other properties can be easily made from this last diagram. Since the areas inside
the force-displacement loops, which are the biggest evaluation criteria for the dissipated energy amount,
are directly related to the force and displacement values, the order to be made according to the dissipated
energy amount will also be the same as the previous orderings. Although the core material with the
highest energy dissipation capacity seems to be superior to the others, if an upper limit is not set for the
core stiffness of the seismic damper, it is inevitable that the steel shims, which are very important for the
stability of the seismic isolator, will be damaged. Soever there are some limitations for the core material
to be used initially to have lower mechanical strength and elasticity properties than steel shims, there is
always the possibility of damage to steel shims due to the rigidity of the core. In order to determine the
possible damage, it is important to include the relevant outputs from the results of the analyzes in the
evaluations. In this context, to evaluate the plastic deformations that may occur in the steel shims of the
analyzed models with alternative core materials, the plastic deformations of the shims of the isolators
returned to their original position at the end of the 2nd cycle are presented in Fig. 7.

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Fig. 7. Scalar plastic strain distribution of models with different core materials.
The results of the analyzes with equivalent plastic deformations are all presented in the same color
scale, in which the red color shows the highest plastic deformation value with 4.2%, and the common
blue color shows the regions without plastic deformation. The largest plastic deformation value in the
shims was obtained for the core material C85700, and almost no plastic deformation was obtained for
the pure lead. Images of plastic deformation outputs on shims of isolators with alternative core materials
are sorted according to plastic deformation damage. This sequence is the same as those of the previous
output presentations of the study, in other words, the amount of plastic deformation seen in the shims
increases with the increase in the ultimate strength values of the core materials.
It is thought that it would be beneficial to know some of the other properties of the materials before
making a final evaluation according to the mechanical properties and analysis results. Recrystallization,
which has some of the parameters that are not traditionally included in performance analyzes or other
mechanical analysis formulas, plays a very important role in reducing the level of problems caused by
exceeding the elongation limits of the material [5, 36, 40, 45-47, 51-53]. Recrystallization property,
permits for orientation and grain size changes, can prevent crack growth and crack propagation. Instead
of creating a fracture, strain can initiate the growth of a new grain or change the size of the existing
grain, by consuming atoms from adjacent pre-existing grains. In this way, the recrystallization process

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allows the material to become more ductile. The starting temperature of the recrystallization property
starts as low as -4 °C for lead, which is a great advantage for lead used as a yielding material [36, 40,
41]. Tin, which has a recrystallization initial temperature of -4 °C, has the same advantage as lead.
Zinc has this advantage to a large extent, with recrystallization starting temperature at 10 °C, which is
below room temperature. However, it is difficult to say that aluminum (80 °C) and brass (~475 °C) have
this advantage [40-42]. It is also important to consider the melting temperatures of the core material to
be used in LRBs, where most of the seismic energy is converted into heat by the core through plastic
deformation [37, 54, 55]. In this context, the approximate melting temperatures of the materials used
in the study, lead (327 °C), aluminum (650 °C), brass (1010 °C), tin-antimony alloy, (246 °C), and zinc
(420 °C) values should also be taken into account [36, 40-43, 47]. Except for experimental cases, it is
unlikely that the amount of heating in LRBs can easily approach the melting temperatures of the lead
core. However, rather than melting, it should be noted that the core material’s strength-related values
will begin to decrease due to the increase in the heat occurring in the core due to the dissipation of the
energy. In this framework, care should be taken in the use of tin-antimony alloy, which has a melting
temperature well below the melting temperature of lead.
CONCLUSION
The study was conducted to ensure that LRBs, one of the most frequently used seismic isolators,
which are one of the important elements of structural sustainability, conform to the definition of
sustainability as much as possible. Materials that are likely to replace the toxic lead material, which
is the most important component of the damping process in LRBs as a yielding metal, have been
investigated. In this framework, representative materials to be used in the analyzes were determined
based on pre-selection criteria such as mechanical, thermal, and castability properties of the materials
as well as their availability. Performance analyzes of the selected materials were made based on a
benchmark model. Since the analysis naturally included stress and deformation information, it was
possible to obtain information not only about the isolator’s performance, but also about the critical
material interactions.
In the analyzes made, the highest dissipated energy amount was found for brass C85700, which has the
highest Young’s modulus, ultimate, and yield stress, as expected. However, although it was not enough
to risk the stability of both brass materials used in the study, it caused a significant amount of damage
to steel shims. As another core material with high mechanical properties, zinc Z19001 and zinc Z13001
come right after brass alloys in terms of performance, the plastic deformation values they create in steel
shims are much lower than those in brass alloys. Plastic deformation values in steel shims are negligible
in cases where aluminum, tin-antimony alloy and lead-calcium alloy used as core material. Almost all of
the materials studied, including the lead-calcium alloy, showed better mechanical performance than the
pure lead. However, within the scope of the examined problem, it is not appropriate to use brass alloys
in a system in the examined configuration due to the damage they cause to steel shims. In addition, the
starting temperature value of the recrystallization, which enables the lead to make high elongations
with minimum damage, is very high in brass alloys and it is not possible for them to benefit from this
advantage.
The performance of the aluminum A01501 is higher than that of lead and the damage to steel shims
is negligible. For this reason, aluminum material has the potential to be used as a yield metal in isolators,
but also disadvantages such as low deformation limit and inability to benefit from recrystallization at
operating temperatures should be considered. Although the lead-calcium alloy, which was included in
the analysis considering that it could be an additional option in the study, performs better than lead, it
has almost the same toxic properties as pure lead in terms of sustainability, only it has a small advantage
such as using less lead material. Leaving the low level of toxicity value aside, tin-antimony alloy is
better than lead in terms of performance and may be considered as an important alternative to lead
because it has the same temperature value for starting recrystallization. However, since it has a very low

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melting temperature compared to the lead, it should be taken into account that there is a possibility that
it may suffer a rapid loss of strength due to heating in cases such as dynamic loadings with long duration
or with high strain rates. Although zinc (Z13001 and Z19001) used as core material in this study caused
some plastic deformation in steel shims, it was concluded that it could be an important alternative to
lead due to its advantages such as high performance, low recrystallization starting temperature and high
melting temperature. In addition to being an alternative to lead in terms of mechanical and performance
properties, it is a well-known fact that zinc is one of the materials with the highest environmental and
sustainability properties. As a natural element zinc has a crucial role in the organic processes of all
plants and animals. In this context, we can say that zinc is the most eco-friendly and sustainable material
among the materials examined. It is thought that the results and evaluations obtained in this study will
guide the LRBs to be more sustainable structural elements.
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4(3) (2011) 281–287. https://doi.org/10.1080/19397038.2011.569583.
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