Page 39 - eBook_Proceedings of the International Conference on Digital Manufacturing V1

Mechanical Performance and Structural Feasibility of Recycled HDPE in
Furniture Design: Experimental and Finite Element Analysis

Tensile tests were performed using a universal testing machine at
a constant crosshead speed of 5 mm/min at ambient temperature
(25 °C). The average tensile strength and elongation at break were
calculated, and standard deviations were reported.

In parallel, the material's modulus of elasticity was determined
from the stress–strain curves. This value was subsequently used in
the Finite Element Analysis (FEA) simulations to ensure material
model consistency between physical testing and computational
modelling.

Design of Experiment

Experimental Procedure and Material Preparation.

The experimental procedure adopted in this research involved a
comprehensive, structured approach designed to rigorously
evaluate the mechanical suitability of recycled high-density
polyethylene (HDPE) from discarded plastic bottles. HDPE
bottles (classification type #2) were specifically chosen for their
favourable mechanical properties, wide availability, and recycling
potential, thus making them ideal candidates for sustainable
seating material.

Initially, post-consumer HDPE bottles were manually
segmented into smaller, manageable pieces, facilitating the
subsequent cleaning and drying phases. The manual segmentation
process ensured precise inspection and removal of non-HDPE
contaminants, crucial in maintaining consistency in the material
properties during testing. The segmented pieces were then
meticulously washed using a detergent solution, thoroughly rinsed
to eliminate residual contaminants, and subsequently dried
naturally at ambient room temperature for 24 hours to ensure
complete removal of moisture, which can adversely affect the
material’s mechanical integrity.

The dried HDPE segments were then subjected to mechanical
crushing, employing a high-efficiency plastic crusher specifically
designed for polymers, to produce uniformly sized flakes.

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