Instrumented Hardness Test on Alumina Ceramics and Single Crystal with Spherical Indenter

Single Crystal of γ-glycine lithium nitrate with non-linear optical material have been grown by slow evaporation method at room temperature. Structural and Crystalline nature of the grown γ-glycine lithium nitrate crystal was confirmed by powder X-ray diffraction technique. UV-Visible transmittance study was performed to analyze optical transparency of γ-glycine crystal and found that the crystal was transparent in the entire visible region. The mechanical properties of the grown crystal was subjected to Vickers hardness test and the Brittleness index (Bi), Fracture toughness (Kc), Elastic stiffness constant (C11) were estimated.

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Effect of ion fluence on the surface morphology of single crystal magnesium oxide implanted with xenon

Journal of Materials Research ◽

10.1557/jmr.1995.2823 ◽

1995 ◽

Vol 10 (11) ◽

pp. 2823-2828 ◽

Cited By ~ 2

Author(s):

Wenbiao Jiang ◽

M. Grant Norton ◽

David B. Poker

Keyword(s):

Atomic Force Microscopy ◽

Surface Morphology ◽

Single Crystal ◽

Magnesium Oxide ◽

Dislocation Loop ◽

Spherical Indenter ◽

Surface Roughening ◽

Force Microscopy ◽

Atomic Force ◽

Oriented Single Crystal

The surface morphology (001)-oriented single-crystal magnesium oxide (MgO) implanted with xenon ions has been examined using atomic force microscopy. It was found that at the lowest fluence used in this study (1.0 × 1014/cm2), a slight roughening of the (001) surface occurred. The magnitude of this roughening remained fairly constant with increases in fluence in the range 1.0 × 1014/cm2 to 3.0 × 1016/cm2. Implantation at fluences of ≥ 1.0 × 1017/cm2 caused significant surface roughening with the concomitant formation of micron-sized blisters. The appearance of some of these blisters resembles the rosette pattern that is also observed when the cleaved surfaces of MgO crystals are etched following indentation using a spherical indenter. This observation suggests that these blisters are formed by the growth of xenon inclusions, during implantation, by a dislocation loop punching mechanism.

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Estimation of Flow Stress of Porous Sintered Metals From Hardness Test With Pyramidal and Spherical Indenters

Journal of Engineering Materials and Technology ◽

10.1115/1.2903193 ◽

1990 ◽

Vol 112 (1) ◽

pp. 95-98 ◽

Cited By ~ 4

Author(s):

T. Tabata ◽

S. Masaki

Keyword(s):

Flow Stress ◽

Relative Density ◽

Surface Area ◽

Uniaxial Compression ◽

Vickers Hardness ◽

Applied Load ◽

Brinell Hardness ◽

Hardness Test ◽

Diameter Ratio ◽

Spherical Indenter

Relationship between hardness and flow stress in uniaxial compression is investigated for porous sintered metals. Hardness is defined here as the applied load divided by the surface area of the indentation. When the semi-angle α of the pyramidal indenter is 68 deg, i.e., the Vickers hardness indenter, the ratio of the hardness to the flow stress decreases with decreasing relative density ρ However, when α is 45 deg, the ratio is 2.7 regardless of the value of ρ. The ratio of the Brinell hardness to the flow stress decreases with decreasing ρ when the diameter ratio d/D of the impression to the spherical indenter is 0.4. When d/D is 0.8, the ratio is nearly constant regardless of ρ. The flow stress of sintered metals can, therefore, be estimated from the hardness measured by the pyramidal indenter with the semiangle of 45 deg or from the Brinell hardness at a diameter ratio of 0.8.

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Synthesis, Growth, Optical, Structural and Mechanical Characterization of SPNP and KPNP Single Crystal using Ethanol as a Solvent

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d4283.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 7782-7785

Keyword(s):

Single Crystal ◽

Mechanical Stability ◽

Green Light ◽

Hardness Test ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Window ◽

Uv Visible ◽

Vicker’S Microhardness

Single crystals of sodium para nitro phenol (SPNP) and potassium para nitro phenol (KPNP) was synthesized at room temperature by slow evaporation solution growth technique using ethanol as a solvent upto the size of 12 × 3 × 2 mm3 and 15 × 2 × 2 mm3 respectively. The grown crystals were characterized by UV- Visible, photoluminescence, Kurtz- Perry test, single crystal X-ray diffraction analysis and Vicker’s microhardness studies. Structural identification of grown crystals was done by single crystal X-ray diffraction and it shows both the crystals are belongs to triclinic crystal system. The SPNP and KPNP crystal emits green light radiation as evident from the PL measurement. The UV -Visible study revealed that the grown crystal has high transmission window with cut off wavelength of 207 nm and 208 nm respectively. And also the direct optical band gap was estimated to be 3.23 eV and 3.20 eV using Tauc’s plot. The SHG output of grown crystals was recorded by Kurtz Perry technique and it is found to be nearly five times greater than the reference KDP. The Vickers hardness test confirms the mechanical stability of the material.

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OS0309 Crystal Plasticity Analysis of Indentation with a Spherical Indenter in Magnesium Single Crystal

The Proceedings of the Materials and Mechanics Conference ◽

10.1299/jsmemm.2012._os0309-1_ ◽

2012 ◽

Vol 2012 (0) ◽

pp. _OS0309-1_-_OS0309-2_

Author(s):

Tsuyoshi MAYAMA ◽

Yuichi TADANO ◽

Hiromoto KITAHARA ◽

Shinji ANDO

Keyword(s):

Single Crystal ◽

Crystal Plasticity ◽

Spherical Indenter

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