Premium
Determination of the R ‐Curve from the Strength—Indentation Load Relation
Author(s) -
Hsueh ChunHway,
Becher Paul F.
Publication year - 1995
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.1151-2916.1995.tb08645.x
Subject(s) - indentation , envelope (radar) , tangent , toughness , function (biology) , curve fitting , mathematics , materials science , composite material , mathematical analysis , geometry , statistics , computer science , evolutionary biology , telecommunications , radar , biology
Strength as a function of indentation load has been measured to evaluate toughness versus crack size curves (i.e., R ‐curves) of ceramics. In the past, this evaluation is achieved by generating a family of global stress intensity versus crack size curves (i.e., K ‐curves) at each indentation load and its corresponding strength, and then fitting an envelope of tangency points to these curves. This envelope yields the R ‐curve. A methodology is proposed in the present study to define the point in the K ‐curve at which the R ‐curve intersects. This methodology complements the conventional “tangency condition” approach in determining the R ‐curve from the experimental strength‐indentation load relation.