Chapter 4 - The families of engineering materials and their properties Flashcards
What is Stiffness is Mechanical Engineering?
An indicator of the tendency for an element to return to its original from after being subjected to a force.
What is Density?
Atomic weight, atom size and packing density.
What is Modulus?
Interatomic bonds and packing density
What is Yield Strength?
Max stress applied before permanent body form change
What is Fracture Toughness
Resistance against crack propagation
How can we do Property Control?
2 ways:
- Composition
- Microstructure
Variants of Material Data
- Numerical
- Non-Numerical
- Additional data, specific
- Additional data, general
Variants of Material Data - Numerical
Properties described by numbers: Density, Modulus, Price
Variants of Material Data - Non Numerical
Properties described by YES or NO (Boolean) or bad-moderate-good (Ranking)
Variants of Material Data - Additional Data, specific
Which experiences are available for the material?
Variants of Material Data - Additional Data, general
What else should be respected?
Important material properties for engineering applications
- Physical Props
- Mechanical Props
- Technological Props
- Usage
- Economics
Structural Steel Sections
Low mass per unit length is more important than low density.
Bending stiffness is maximized
What is an Alloy?
Mixture of two or more chemical components, most of time one of them is a metal
Polymers Classification
- Plastics
- Polymers
- Thermoplastics
- Thermosets
- Elastomers
- Thermoplastic Elastomers
