The microhardness indentation load/size effect in rutile and cassiterite single crystals

Indentation Load-Size Effect in Al2O3 — SIC Nanocomposites The indentation load-size effect (ISE) in Vickers hardness of Al2O3 and Al2O3 + SiC nanocomposites has been investigated and analysed using Meyer law, proportional specimen resistance (PSR) model and modified proportional specimen resistance (MPSR) model. The strongest ISE was found for alumina. Both the PSR and MPSR models described the ISE well, but the MPSR model resulted in slightly lower true hardness values for all materials investigated. No evidence of the effect of machining stresses on the ISE has been found.

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Indentation Testing of an Al2O3/Al2O3 + ZrO2 Layered Composite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.290.316 ◽

2005 ◽

Vol 290 ◽

pp. 316-319

Author(s):

Peter Zimovčák ◽

Tibor Köves ◽

Ján Dusza ◽

Ladislav Pešek ◽

Francis Chalvet ◽

...

Keyword(s):

Fracture Toughness ◽

Residual Stresses ◽

Size Effect ◽

Vickers Hardness ◽

Layered Composite ◽

Indentation Load ◽

Indentation Fracture ◽

Depth Sensing ◽

The Individual ◽

Load Size

Micro- and macro-hardness of the individual layers of an Al2O3 / Al2O3 + ZrO2 layered composite have been investigated. The indentation load size effect has been studied in a range of indentation load of 25 mN – 100 N using depth sensing indentation technique and conventional Vickers hardness testers. Fracture toughness values of the layers have been measured using indentation fracture method. The effect of residual stresses on the KIC value has been analyzed.

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Nanohardness of Individual Phases in WC – Co Cemented Carbides

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.586.23 ◽

2013 ◽

Vol 586 ◽

pp. 23-26 ◽

Cited By ~ 3

Author(s):

Annamária Duszová ◽

Radoslav Halgaš ◽

Pavol Priputen ◽

Marek Bľanda ◽

Pavol Hvizdoš ◽

...

Keyword(s):

Size Effect ◽

Significant Influence ◽

Crystallographic Orientation ◽

Grain Orientation ◽

Indentation Load ◽

Cemented Carbides ◽

Indentation Modulus ◽

Instrumented Indentation ◽

Load Size

The nanohardness of WC – Co hardmetals has been investigated using instrumented indentation and Berkovich tip indenter. The nanohardness, HIT, and indentation modulus, EIT, of Co phase and individual WC grains and the influence of their crystalographic orientation have been studied. SEM, AFM and EBSD methods were used for the characterization of the microstructures and indents and for the identification of crystallographic orientation of WC grains, respectively. Strong indentation load-size effect and significant influence of the crystallographic orientation of WC crystals on HIT and EIT have been found. The nanohardness of Co binder was approximately 10 GPa and that of WC grains varied between 25 and 50 GPa, depending on the grain orientation and load. The nanohardness values of the basal and prismatic planes of individual WC grains at load of 10 mN were 40.4 ± 1.6 GPa and 32.8 ± 2.0 GPa, respectively.

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