Strength, hardness, ductility, toughness and stiffness.
Strength (yield, ultimate), stiffness (E), ductility (% elongation, reduction of area), toughness (energy to fracture), hardness, fatigue strength and creep resistance. Each is measured by standard tests; designers need combinations, not single numbers.
Titanium alloys have a very high specific strength, valuable in aerospace.
Mechanical property definitions are the common language for comparing materials, so knowing what each measures prevents wrong choices.
Strength, hardness, ductility, toughness and stiffness.
Mechanical property definitions are the common language for comparing materials, so knowing what each measures prevents wrong choices.
Strength is the stress a material can carry before permanent deformation or fracture. Toughness is the energy it absorbs before fracture, which includes the ability to deform.
Hardness measures resistance to indentation, which correlates with strength in metals but is not a direct measure of it.
Typical applications include choosing a material that resists wear but is not too brittle for a shaft, comparing the stiffness of two plastics for a housing and deciding whether a part needs more toughness or more hardness.
Study "Diffusion" first (topic 7 of 100 in Materials & Chemical). It covers the groundwork this topic builds on.
Elastic vs plastic. True stress-strain. Specific strength σ/ρ.
Titanium alloys have a very high specific strength, valuable in aerospace.
The next topic is "Hardness testing", which builds directly on this one.
It is classed as Beginner in Materials & Chemical (topic 8 of 100). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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