Indentation of power law creep solids by self-similar indenters

Abstract

a b s t r a c tFor creep solids obeying the power law under tension proposed by Tabor, namely = bε m , it has been established through dimensional analysis that for self-similar indenters the load F versus indentation depth h can be expressed ashere the dimensionless factor˘˛depends on material parameters such as m and the indenter geometry. In this article, we show that by generalizing the Tabor power law to the general three dimensional case on the basis of isotropy, this factor can be calculated so that indentation test can be used to determine the material parameters b and m appearing in the original power law. Hence indentation test can replace tension test. This could be a distinct advantage for materials that come in the form of thin films, coatings or otherwise available only in small amounts. To facilitate application values of this constant are given in tabulated form for a range of material parameters.

Non-destructive test of steel structures by conical indentation

“…In practice widly known indenters in the form of a sphere [8,9], cone [10,11], pyramid, flat punch [12]. A large amount of testing of materials in industry poses the problem of the real structure testing instead of laboratory standart method.…”

Metal structures diagnosis by truncated cone indentation

“…The choice of the shape of the indenter in this case is an important task [8]. Most common in modern practice are indenters in the form of a sphere [9,10], cone [11,12], pyramid, flat punch [13], but they have one significant drawback -the complexity of the registration of the beginning of plastic flow. Great practical interest is the study of the influence of basic background stresses in the existing structures, under load, by the methods of indentation.…”