Question

A brittle material is subjected to a tensile stress of 1.65 MPa. If the specific surface energy and modulus of elasticity for this material are 0.60 J/m2 and 2.0 GPa, respectively. What is the maximum length of a surface flaw that is possible without fracture

Answer 1

Answer:

The maximum length of a surface flaw that is possible without fracture is

$2.806 \times 10^{-4} m$

Explanation:

The given values are,

σ=1.65 MPa

γs=0.60 J/m2

E= 2.0 GPa

The maximum possible length is calculated as:

$\begin{gathered}a=\frac{2 E \gamma_{s}}{\pi \sigma^{2}}=\frac{(2)\left(2 \times 10^{9} \mathrm{~N} / \mathrm{m}^{2}\right)(0.60 \mathrm{~N} / \mathrm{m})}{\pi\left(1.65\times 10^{6} \mathrm{~N} / \mathrm{m}^{2}\right)^{2}} \\=2.806 \times 10^{-4} \mathrm{~m}\end{gathered}$

The maximum length of a surface flaw that is possible without fracture is

$2.806 \times 10^{-4} m$