Mechanical and Chemical Properties of Materials

Flashcards covering key concepts related to the mechanical and chemical properties of materials discussed in the lecture.

What is tensile strength?

The ability of a material to withstand tensile (pull) forces until it becomes thinner or is destroyed.

Define Young's modulus.

A measure of the stiffness of a material, calculated as stress divided by strain (E = σ/ε).

What does Mohs hardness measure?

The hardness of a material determined by scratching it against other minerals.

What is fracture toughness?

The ability of a material to resist the propagation of an existing fracture when subjected to load.

What is specific weight used for in mechanical engineering?

It determines the weight of a structure designed to carry loads while remaining within limits of deformation.

What are the properties of conductors?

Conductors have high electrical conductivity, high thermal conductivity, and allow free electron flow on their surface.

What is the significance of the band gap in materials?

The energy required to promote an electron from the highest to the lowest energy state; affects electrical properties of insulators, semiconductors, and metals.

How are semiconductors defined?

Materials that conduct electricity under some conditions but not others, making them suitable for current control.

What are the characteristics of dielectrics or insulators?

They have low conductivity, can be polarized by applying an electric field, and typically exhibit high oxidation and corrosion resistance.

What is ferromagnetism?

The strong attraction to magnetic fields, where materials retain magnetization even after the field is removed.