What are the three types of mechanical behavior (stress/strain curves) during tensile test? What are the types of materials that have these three types of mechanical behavior respectively?

The three types of mechanical behaviour (stress/strain curve) and their materials includes:

1. Perfectly Elastic: Glass, Ceramics, Cast Iron etc

2. Rigid Plastic: Cups, High Density Polyethelene tubs, Similar food containers etc

3. Elastic, Perfectly Plastic: solid shaft, Lead etc

Explanation:

1. In Perfectly Elastic Materials, there is negligible yielding. Here the stiffness of the material is indicated

2. In Rigid plastic: the materials continue to deform at the same rate/level once stress level has reached the yeild point.

3. In Elastic Perfectly Plastic: this is a combination of both perfectly elastic and rigid plastic, materials heated at a very high temperature behave in a way that it will undergo recovery when loading.

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