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Oas Secretary-General Regrets The “Hardness” Of The Law In Alabama : http://newish.info/12662-oas-secretary-general-regrets-the-hardness-of-the-law-in-alabama

Oas Secretary-General Regrets The “Hardness” Of The Law In Alabama ! http://newish.info/12662-oas-secretary-general-regrets-the-hardness-of-the-law-in-alabama

“Softness triumphs over hardness, feebleness over strength. What is more malleable is always superior over that which is immovable. This is the principle of controlling things by going along with them, of mastery through adaptation.”

—Lao-tzu

“And hardness it sets in. You need some protection, the thinner the skin. ”

—Kite

23-27. Spain Does Not Wrinkle At The German Hardness And Adds His Third Win ! http://newish.info/186429-23-27-spain-does-not-wrinkle-at-the-german-hardness-and-adds-his-third-win

“I love her for what she has dared to be, for her hardness, her cruelty, her egoism, her perverseness, her demoniac destructiveness. She would crush me to ashes without hesitation. She is a personality created to the limit." ”

— Anais Nin
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Properties of Materials: "The Rest" Part II Hardness

Hardness

  • Resistance to indentation/plastic deformation
  • Harder the material, smaller the indent after an applied load
  • Determind by load/projected area of indent
  • non-SI units of Force/Area, kgf/mm^2 - can be converted to MPa by multiplying by g. Converted value is then appoximately 3x yield stress
  • Made on surface of material, non-destructive, and therefore ideal for quality control and measuring surface properties post treatments
  • Vickers test uses a diamond, pyramid shape. Hv = F/A
  • Resistance to permanently indenting the surface
  • Large resistance = resistant to plastic deformation, or cracking under compression/high strength
  • Large resistance = better wear properties
  • Polymers < Alluminium Alloys, Brass < Easy Machine Steels < File Hard < Cutting Tools < Nitrided Steels < Diamond
  • As deformation is compressive, can’t test on ceramics
  • Lead < Annealed Alluminium < Annealed Copper < Steel < Tungston Carbide < Alumina < Diamond - Hardness and yield strength
  • Material selection isn’t driven by hardness, but it is a good indication of yield strength and resistance to wear and indentation
  • Good for a rapid assessment of properties, used for quality inspections between batches, ensuring that processing and heat treatments have the desired effect
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