Backing Materials For Stab Armor Testing
Stab and spike armor standards have been developed using 3 different backing materials. The Draft EU norm calls out Roma clay, The California DOC called out 60% ballistic gelatin and the current standard for NIJ and HOSDB calls out a multi-part foam and rubber backing material.
- Using Roma clay backing, only metallic stab solutions met the 109 joule Calif. DOC ice pick requirement
- Using 10% Gelatin backing, all fabric stab solutions were able to meet the 109 joule Calif. DOC ice pick requirement.
- Most recently the Draft ISO prEN ISO 14876 norm selected Roma as the backing for both ballistics and stab testing.
This history helps explain an important factor in Ballistics and Stab armor testing, backing stiffness affects armor penetration resistance. The energy dissipation of the armor-tissue system is Energy = Force x Displacement when testing on backings that are softer and more deformable the total impact energy is absorbed at lower force. When the force is reduced by a softer more compliant backing the armor is less likely to be penetrated. The use of harder Roma materials in the ISO draft norm makes this the most rigorous of the stab standards in use today.
Read more about this topic: SN-42
Famous quotes containing the words backing, materials, stab, armor and/or testing:
“Better risk loss of truth than chance of error—that is your faith-vetoer’s exact position. He is actively playing his stake as much as the believer is; he is backing the field against the religious hypothesis, just as the believer is backing the religious hypothesis against the field.”
—William James (1842–1910)
“What is most interesting and valuable in it, however, is not the materials for the history of Pontiac, or Braddock, or the Northwest, which it furnishes; not the annals of the country, but the natural facts, or perennials, which are ever without date. When out of history the truth shall be extracted, it will have shed its dates like withered leaves.”
—Henry David Thoreau (1817–1862)
“Because of the unusual remoteness of Russia, and because of nostalgia’s remaining throughout one’s life an insane companion, with whose heartrending oddities one is accustomed to put up in public, I feel no embarrassment in confessing to the sentimental stab of attachment to my first book.”
—Vladimir Nabokov (1899–1977)
“Such was the very armor he had on
When he the ambitious Norway combated.”
—William Shakespeare (1564–1616)
“No testing has overtaken you that is not common to everyone. God is faithful, and he will not let you be tested beyond your strength, but with the testing he will also provide the way out so that you may be able to endure it.”
—Bible: New Testament, 1 Corinthians 10:13.