Study of Microhardness and Its Related Physical Constants of Ferroelectric Glycine Phosphite (GPI) Single Crystals
TL;DR: In this article, the variation of hardness on (010) plane of monoclinic GPI crystals, (NH3CH2COOH3PO3), with load was studied, and fracture toughness values, determined from measurements of crack lengths, were estimated to be 0.1266 MN/m3/2, the brittleness indices "B i" were estimated as 4270.7 m−1/2.
Abstract: The ferroelectric crystals of Glycine Phosphite were grown by low temperature solution growth technique. The variation of hardness on (010) plane of monoclinic GPI crystals, (NH3CH2COOH3PO3), with load was studied. Vickers hardness, H v and Knoop hardness numbers, H k were found to decrease with an increase in load. Meyer's index ‘n’ was found to be less than 2 showing soft-material characteristics. The fracture toughness values ‘K c’, determined from measurements of crack lengths, were estimated to be 0.1266 MN/m3/2, The brittleness indices ‘B i’ were estimated as 4270.7 m−1/2. Elastic stiffness coefficient, C 11 and Young's modulus were calculated from the hardness.
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TL;DR: In this article, organic nonlinear optical l-phenylalanine d-mandelic acid (LPDMA) single crystals have been harvested adopting slow solvent evaporation solution growth technique (SSEST) with growth period of 15 days.
Abstract: Organic nonlinear optical l-phenylalanine d-mandelic acid (LPDMA) single crystals have been harvested adopting slow solvent evaporation solution growth technique (SSEST) with growth period of 15 days. The XRD studies of the crystal confirm the non-centrosymmetric nature of the crystal. The presence of functional groups for the formation of the compound was confirmed by Fourier Transform Infrared (FTIR) analysis. The UV–Visible spectral studies ascertained linear optical quality and estimation of optical parameters. The nonlinear optical property was studied from Kurtz-Perry powder technique and Z-scan technique. The quantum chemical calculations such as HOMO–LUMO and Molecular Electrostatic Potential (MEP) were calculated and presented. In order to find out various mechanical parameters such as Vicker’s hardness number (Hv), Mayer’s index (n), yield strength (σy) and stiffness constant (C11), Vicker’s microhardness tester was utilized.
20 citations
Cites background from "Study of Microhardness and Its Rela..."
...The hardness properties are basically related to the crystal structure of the material and hardness studies are carried out to understand the plasticity of the crystal [20, 21]....
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TL;DR: In this article, a new organic nonlinear optical material piperazinium (bis) hydrogen succinate single crystal (PPHS) was synthesized by the slow evaporation method.
14 citations
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TL;DR: In this article, a single crystal of urea oxalic acid was grown by slow evaporation method and the lattice parameters are a =5.13 A, b =12.48 A, c =7.07 A, β =98.13° with V =448.5 A 3.
13 citations
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17 Feb 2015TL;DR: In this paper, the semiorganic crystals of potassium boro-succinate (KBS) were grown by slow evaporation method and the microhardness study has been carried out over a load range of 25-100 g.
Abstract: The semiorganic crystals of potassium boro-succinate (KBS) were grown by slow evaporation method. KBS crystallizes in monoclinic system which was confirmed by powder XRD analysis. Vickers microhardness study has been carried out over a load range of 25-100 g. The Vickers hardness numbers (Hv) of the material increases as the load increases so the material is suitable for device fabrication. The Meyer index 'n' is estimated to be greater than 1.6, the crystal system belongs to the soft material category. The elastic stiffness coefficient, c11, has also been calculated using Wooster's empirical relation from the hardness data. The fracture toughness values 'Kc', determined from measurements of crack lengths, were estimated to be 0.15166 MN/m3/2. The brittleness indices 'Bi' were estimated as 276 m−1/2.
12 citations
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TL;DR: In this paper, single crystals of tri-glycine barium nitrate (TGBN) were grown from aqueous solution employing the techniques of slow cooling under controlled evaporation.
Abstract: Single crystals of ferroelectric material tri-glycine barium nitrate (TGBN) were grown from aqueous solution employing the techniques of slow cooling under controlled evaporation. Highly transparent seed crystals were harvested after repeated recrystallization process. Optical quality seed crystal has been used for the bulk growth. The solubility of the synthesized material was determined by using water as solvent. The solubility of TGBN was determined for various temperatures between 20°C and 50°C. It is found that this material has a positive temperature coefficient of solubility. Single crystal X-ray diffraction analysis confirms the crystal structure. The FTIR analysis confirms the presence of functional groups in the complex. The Vicker's microhardness of the samples were found using Mitutoyo MH 120 microhardness tester. The measurements were done at room temperature for different forces.
8 citations
References
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01 Jan 1973561 citations
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TL;DR: A survey of the relation between four physical properties of crystals and their structural characters is given in this paper, where the properties discussed are the magnetic, optical, piezoelectric and elastic.
Abstract: A survey is given of the relation between four physical properties of crystals and their structural characters. The properties discussed are the magnetic, optical, piezoelectric and elastic. The well-established relations between (a) diamagnetic anisotropy and molecular orientation and (b) paramagnetic anisotropy and the environment of complex ions are briefly reviewed. The more recent study of paramagnetic resonance absorption at high frequencies in a magnetic field is also included. The work on antiferromagnetic crystals is discussed in connection with the spinels. The study of optical activity and Raman spectra are considered under the heading of optical properties. The experimental confirmation by X-rays of the original convention concerning atomic configurations and the sign of optical activity in a molecule are described and also the connection between special features of the structures of tartrates, of sodium chlorate and of quartz and the handedness of the rotatory power is analysed. The piezoelectric properties of zinc blende, quartz, tourmaline, Rochelle salt and potassium dihydrogen phosphate are considered in relation to their structures. In the study of quartz and tourmaline the origin of the piezoelectric charge is attributed to tetrahedra of SiO4 stressed in a direction from one corner to the opposite face. The spontaneous electric polarization of Rochelle salt and KH2PO4 is attributed to cooperative movements of hydrogen ions. Broad generalizations concerning the relation between elastic constants and the crystal structure are given. It is shown that the hardness increases in a regular way with the elastic constant c11 (or an average of c11, c22, c33) and also that there is a close connection between directions of strong interatomic bonds and a large value of the corresponding elastic constant.
365 citations
"Study of Microhardness and Its Rela..." refers methods in this paper
...The elastic stiffness constant (C11) was calculated by Wooster’s empirical relation [14]....
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25 May 2005-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, a Vickers microhardness study has been carried out on (1 − 0 -0) and (0 − 1 − 0) faces of single crystals of magnesium sulphate hepta-hydrate (MgSO 4 ·7H 2 O) over a load range of 10 − 80 ǫ.
Abstract: A Vickers microhardness study has been carried out on (1 0 0) and (0 1 0) faces of solution-grown single crystals of magnesium sulphate hepta-hydrate (MgSO 4 ·7H 2 O) over a load range of 10–80 g. The Vickers hardness numbers ( H v ) are found to decrease initially with increase in load and then appear to level-off. The (1 0 0) face is the softest one. The Meyer index ‘ n ’ of the two faces is less than 2 as expected theoretically if the particular crystal system belongs to the soft material category. Neither Kick's law nor Hays and Kendall's law can fully explain the nonlinear variation of microhardness with load. Instead, preference is given to Li and Bradt's proportional specimen resistance (PSR) model. The elastic stiffness coefficient, c 11 , has also been calculated using Wooster's empirical relation from the hardness data and it shows reasonable agreement with a reported value. A hardness anisotropy for both planes has been observed in accordance with the orientation of the crystallographic planes.
115 citations
"Study of Microhardness and Its Rela..." refers background in this paper
...The Meyer’s law, gives an expression regarding load and size of indentation [12]:...
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