Premium
Measurement of Dynamic Hardness by Controlled Sharp‐Projectile Impact
Author(s) -
MARSHALL DAVID B.,
EVANS ANTHONY G.,
NISENHOLZ Z.
Publication year - 1983
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1983.tb10095.x
Subject(s) - quasistatic process , indentation , materials science , projectile , composite material , cracking , indentation hardness , hardness , contact mechanics , contact area , structural engineering , metallurgy , microstructure , finite element method , thermodynamics , physics , engineering
Impact of ZnS by a pyramidal projectile was used to provide a measurement of the dynamic hardness and to obtain direct comparison of the contact damage produced by static loading and impact. The dynamic hardness was evaluated from measurements of residual contact dimensions as a function of impact velocity, over the velocity range 5 to 40 m.s ‐1 . The value obtained ( H d =5.0 GPa) was higher than the static hardness ( H S = 1.9 GPa). The higher hardness in impact causes more extensive cracking, an increase in the elastic recovery of the depth of the residual contact impression, and a smaller plastic zone surrounding the contact site. The relative extents of cracking in impact and static loading are predicted by a quasistatic indentation fracture mechanics analysis along with the appropriate values of hardness.