3 ms·
You might find it interesting that toughness and "won't shatter when dropped" are different things. Toughness(G) = slowly absorb energy without fracture. Shat
by vlehto 11y ago
You might find it interesting that toughness and "won't shatter when dropped" are different things.
Toughness(G) = slowly absorb energy without fracture.
Shattering is more dependable of:
Fracture toughness(Kc) = (E*G)^0,5
Where E = modulus. That explains why plastics with low E shatter easily while being tough. Metals have additional hardening methods that allow them to go beyond this rule.
PS. Your knowledge on the subject is already what I'd wish laymen had. So I really don't mean any offense.
- blt 11y agoNone taken, thanks for the info!
- personjerry 11y agoTo clarify, is fracture toughness the ability to withstand a sudden increase in energy?
- vlehto 11y agoNot really.. I had kind of error there. It's still often toughness when you wish to study how material reacts to sudden increases in (kinetic)energy. Fracture toughness describes relation between maximum tension and maximum depth of pre-existing crack that still doesn't launch phenomena called "fast fracture". https://en.wikipedia.org/wiki/Fast_fracture https://en.wikipedia.org/wiki/Fast_fracture It's highly relevant in many cases, because most real world materials have microscopic cracks. And because the load where fast fracture might happen is often lot smaller than yield load. Curiously Charpy impact test still indicates more toughness than fast fracture. But it's never used to quantify toughness in real life. https://en.wikipedia.org/wiki/Charpy_impact_test https://en.wikipedia.org/wiki/Charpy_impact_test Thanks for that comment. I need to clear this stuff bit more in my head.