This document compares various materials for use as smartphone shells based on their fracture toughness, thermal conductivity, stiffness, embodied energy, and other properties. It presents data on aluminum, polycarbonate, carbon fiber reinforced polymer (CFRP), epoxies, and polymethyl methacrylate (PMMA) in tables and charts. The objective is to optimize fracture toughness while minimizing mass. Polycarbonate has the best material index values for thermal conductivity and embodied energy, while aluminum ranks highest for stiffness and CFRP for fracture toughness. The conclusion is that polycarbonate may be the best material for smartphone shells based on the design criteria and objectives.
6. Design
Criteria:
•To protect the core system of a
smartphone.
•The compression and tension which
happen in bending can affect the
functionality of the phone and might
as well causes the phone to break
easily
•To avoid any plastic deformation
•Assumption: the shell must be an
elastic beam
10. Table of Materials and their Material Indices
Material Fracture Toughness/MPa*m^1/2 YieldStrength/MPa Material Index
Aluminum 35 500 0.07
CFRP 88 1050 0.083809524
Magnesium 18 400 0.045
Polycarbonate 4.6 70 0.065714286
Epoxies 2.22 71.7 0.030962343
PMMA 1.6 72.4 0.022099448
Table 1
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