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Page 8 of 13 Kumar et al. Vessel Plus 2019;3:35 I http://dx.doi.org/10.20517/2574-1209.2019.006

Figure 7. Relation among von-mises stresses and different load cases

Finite element simulation
Explicit solver (ABAQUS 6.10) was used to carry out simulations, which was used to produce to the
expansion of the balloon. Considering artery and plaque for the non linear pressure analysis of stent
expansion, for the stent inflation balloon was used as a medium for which various pressure load cases was
performed to know the mechanical behaviour of artery and stent, such as radial displacement of artery and
stent, von-mises stresses sharing of artery and stent and plastic strains at plaque and non-plaque regions.

RESULTS
Many researchers elaborated in their work, Co-Cr L605 alloy stent implant has higher modulus of
elasticity; owing to higher level of stresses developing in stent expansion which affects the coronary artery
during stent expansion, hence chances of vessel damage is very high. To overcome these problems, the
alternate material is essential for the cardiovascular stent implants. The results of PEEK450G stent implant
has discussed in following two methods.

Non-linear bending analysis
Von-mises stresses
The results of non-linear bending analysis of coronary stent by using PEEK 450G as shown in Figure 3. It
is observed that the stresses developed in case of PEEK 450G stent when subjected to different loading cases,
i.e., 1 mm displacement, 2 mm displacement with 0.1 radian rotation, 0.15 radian rotation and 0.25 radian
rotation are 7 MPa, 16 MPa, 11 MPa and 19 MPa as shown in Figure 7. The stresses generated in PEEK 450G
[15]
is very lesser and well below the yield function of the material, i.e., 100 MPa . The bending of coronary
[14]
stent causes high stresses on artery may injure the coronary artery . Hence, PEEK 450G has an ideal
material in terms of flexibility and stability, also recommended for future coronary stent implants.

Non-linear pressure analysis
Radial displacement
The results obtained for PEEK 450G stent in terms of radial displacement, when subjected to 0.8 MPa
pressure load case as shown in Figure 8. Radial displacement of PEEK 450G stent against the expanding
pressure at non-plaque region as shown in Figure 9. As can be seen in Figure 9, maximum radial
displacement is observed for the maximum pressure of 1.2 MPa. It is observing that the radial displacement
of PEEK 450G is 1.4 mm for the pressure load of 1.2 MPa at non-plaque. Figure 10 represents the relation
between radial displacement and pressure at plaque region. The radial displacement of PEEK 450G is