In reality not all stress strain curves perfectly resemble the one shown in strain figure 6 2.
Stress strain curve of metals ceramics and polymers.
Elastic energy ductile fracture.
Stress strain curves for metals ceramics and polymers objective we are interested about studying and comparing stress strain curves of metals ceramics and polymers.
Primarily differences are due to their different chemical bonding properties homework 1.
A typical stress strain curve would look like figure 6 2strain curve.
Stress strain curve is the plot of stress and strain of a material or metal on the graph.
The stress strain curve for metals ceramics and polymers the curve i have shown you is a typical curve for ductile materials.
After plotting the stress and its corresponding strain on the graph we get a curve and this curve is called stress strain curve or stress strain diagram.
Plasticity happens when the atoms slip when they break bonds and reform new ones.
This stress curve is typical for ductile metallic elements.
Metals and its alloys contain atoms that are arranged in orderly manner.
Approximate by the area under the stress strain curve brittle fracture.
A highly elastic polymer may stretch over 10 times the original length before breaking while a metal might elastically stretch 10 of the original length elastically and may stretch plastically to double the original length before reaching its fracture point.
Based on the mentioned properties.
The stress shown in is an example of a textfigure 6 2 book stress strain curve.
The yield point is the maximum of the stress strain curve the weird circle symbol.
Metallic bonding is great for this sort of re bonding which is why metals are usually ductile.
It makes them dense and eventuall.
While some of the stress strain curves for polymers might look similar to ones for metals polymers are mechanically different than metals or ceramics.
For brittle ceramics a three point bending apparatus shown in the figure below is used determine the stress strain behavior and the measurement results are used to calculate an equivalent modulus of elasticity.
The linear portion of the curve is the elastic region and the slope is the modulus of elasticity or young s modulus.
In this the stress is plotted on the y axis and its corresponding strain on the x axis.
Elasticity ductility and tensile strength those four materials can be simplified by these definitions.
Elastic plastic energy very small toughness unreinforced polymers engineering tensile strain ε engineering tensile stress σ small toughness ceramics large toughness metals adapted from fig.
Difference between metals ceramics and polymers with respect to modulus and tensile strengths the modulus values for highly elastic polymeric materials are lower than those of metals.
