A simple method to evaluate anisotropic plastic properties based on dimensionless function of single spherical indentation – Application to SiC whisker-reinforced aluminum alloy

Influence of sample thickness and experimental device configuration on the spherical indentation of AISI 1095 steel

“…Some studies have also considered anisotropic materials and proposed to use the geometry of the residual imprint as additional information. 17,18 The main advantages of the indentation test compared, for instance, to the tensile test, are the local probing of mechanical characteristics and the few restrictions on the sample shape and size. However, most of the theoretical and numerical models proposed so far consider infinite sample dimensions compared to the indenter radius, which implies no influence on the indentation response.…”

Determining the stress level of monotonic plastically pre-hardened metal sheets using the spherical instrumented indentation technique

“…The work-hardening law of the studied material is built by determining various − values (representative stresses and strains). In the second approach, the work-hardening law is no longer built by determining various − values but by determining its mechanical parameters [7][8][9][10][11][12][13][14][15][16]. In all these studies, the work-hardening law of the studied materials is considered as a Hollomon law.…”

“…Even though these studies [7][8][9][10][11][12][13][14][15][16] are based on the same approach, they rely on different hypotheses making them more or less accurate depending on the studied case. On one hand, the model of Taljat et al [7] uses the penetration depth h, the contact radius r and the indentation effort F of a spherical indenter for determining the plastic parameters of A c c e p t e d m a n u s c r i t p t the Hollomon law.…”

Deducing the stress–strain response of anisotropic Zr–2.5%Nb pressure tubing by spherical indentation testing

“…Several methods have been proposed to determine the average representative stress r avg from spherical indentation load-depth data. While these methods usually assume that the indentation is made in mechanically isotropic material [2][3][4][5][7][8][9][10][11][12][13][14], several researchers have considered, with the application of numerical simulation and other techniques, the spherical indentation of mechanically anisotropic material [6,[15][16][17][18]. In this paper we present an improved procedure for determining r avg for a mechanically anisotropic material, extruded and cold-drawn Zr-2.5%Nb CANDU pressure tubing, which is based upon the application of equations developed to express r avg of an isotropic material along with an expression to account for the mechanical anisotropy in terms of the Hill's anisotropy coefficients of the indented material.…”

“…While the average stress r avg resulting from spherical indentation must be proportional to the average indentation contact pressure, the actual proportionality is complex and has been much studied [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]21,22]. The following equation expresses r avg for the case of spherical indentation involving elastic-plastic deformation of an isotropic work-hardening material [21] …”