In this research, atomic force microscopy (AFM) with a flat tip cantilever is utilized to measure Young's modulus of a whole yeast cell (Saccharomyces cerevisiae BY4741). The results acquired from AFM are similar to those obtained using a microfluidic chip compression system. The mechanical properties of single yeast cells are important parameters which can be examined using AFM. Conventional studies apply AFM with a sharp cantilever tip to indent the cell and measure the force-indentation curve, from which Young's modulus can be calculated. However, sharp tips introduce problems because the shape variation can lead to a different result and cannot represent the stiffness of the whole cell. It can lead to a lack of broader meaning when evaluating Young's modulus of yeast cells. In this report, we confirm the differences in results obtained when measuring the compression of a poly(dimethylsiloxane) bead using a commercial sharp tip versus a unique flat tip. The flat tip effectively avoids tip-derived errors, so we use this method to compress whole yeast cells and generate a force–deformation curve. We believe our proposed method is effective for evaluating Young's modulus of whole yeast cells.

Illitic clay from the locality of Liepa, Latvia, was investigated using dynamic thermomechanical analysis during the heating and cooling stages of firing. Differential thermal analysis, thermogravimetry, thermodilatometry, X-ray diffraction and porosimetry were also performed to shed light on the processes influencing the elastic properties of clay. The increase in the Young's modulus (YM) at low temperatures was linked to the release of physically bound water. Above 850°C, the bulk density and YM both increased as a consequence of sintering. The YM was more sensitive to the progress of sintering compared to dimension changes. The YM values continued to increase during cooling until the glass-transition temperature was reached. At this temperature, the first microcracks caused by the differences in thermal expansion coefficients of the present phases were expected to appear. The YM showed a sharp V-shaped minimum at the β → α transition of quartz, which was a result of alternation of the mechanical radial stresses around the quartz grains. When the transition of quartz was completed, the YM continued to decrease because microcracks were still being created at the boundaries between the different phases. The decrease of the YM during cooling from the glass-transition temperature down to room temperature was ~50% for all of the firing temperatures and isothermal periods applied.

Here, different tissue surfaces of tomato root were characterized employing atomic force microscopy on day 7 and day 21 of growth through Young's modulus and plasticity index. These parameters provide quantitative information regarding the mechanical behavior of the tomato root under fresh conditions in different locations of the cross-section of root [cell surface of the epidermis, parenchyma (Pa), and vascular bundles (Vb)]. The results show that the mechanical parameters depend on the indented region, tissue type, and growth time. Thereby, the stiffness increases in the cell surface of epidermal tissue with increasing growth time (from 9.19 ± 0.68 to 13.90 ± 1.68 MPa) and the cell surface of Pa tissue displays the opposite behavior (from 1.74 ± 0.49 to 0.48 ± 0.55); the stiffness of cell surfaces of Vb tissue changes from 10.60 ± 0.58 to 6.37 ± 0.53 MPa, all cases showed a statistical difference (p < 0.05). Viscoelastic behavior dominates the mechanical forces in the tomato root. The current study is a contribution to a better understanding of the cell mechanics behavior of different tomato root tissues during growth.

The dependence of polymer properties on their processing history can be used advantageously. Polyethylene terephthalate (PET), a semi-crystalline polymer, exhibits a microstructure reliant on process and thermal history. PET undergoes strain-induced crystallization, making it sensitive to mechanical stretching. As the level of crystallinity in PET governs its mechanical behavior, it is necessary to quantify the effect of crystallinity and molecular orientation for efficient use. The present research is focused on an approach that will aid in correlating the stretch ratio of PET films to the percent crystallinity and mechanical properties. PET films with different local stretch ratios were obtained through bi-axially stretching injection-molded cylinders of increasing thickness and weight. Percent crystallinity of the PET films with different stretch ratios was measured using X-ray diffraction. Film samples were marked with respect to the stretch directions for measuring their longitudinal (primary stretch direction) and transverse mechanical properties. Local molecular orientation in the form of pole figures was mapped using the (100) plane corresponding to the PET lattice. This will help in linking the physical sample directions and processing to the molecular orientation. Associating the mechanical properties with molecular alignment helps in designing production processes that realize the material's structural potential.

Electron backscatter diffraction (EBSD) was employed to analyze the microstructure and texture of four different Alloy 82H gas tungsten arc welds that previously underwent static and dynamic modulus testing. The Young's moduli were shown to differ among the various welds, but also within each weld, dependent upon the direction measured. These differences were attributed to anisotropy of the crystallographic textures, which were described using inverse pole figures with respect to each of the weld's three orthogonal axes. The Young's modulus demonstrated a strong correlation with the texture, consistent with single crystal experiments. Sample directions containing a large population of {100} orientations had the lowest Young's modulus, while those with {111} grains possessed the highest. Microstructures with {110} textures were closer to the average modulus value of 207 GPa (30.0 Msi). X-ray diffraction texture measurements on four samples were used to verify the EBSD results.

The stationary values (maximum, minimum, saddle point) of Young modulus E(n) for a general anisotropic elastic materials is studied. The general results are then spcialized for monoclinic materials. Equations that provide the direction n for a stationary value are given. Some have an explicit solution. Other may require a numerical computation. The equations that required numerical solutions are two coupled polynomials of degree no more than four.

Explicit expressions of the direction n and the stationary values (maximum, minimum and saddle point) of Young's modulus E(n) for orthotropic, tetragonal, trigonal, hexagonal and cubic materials are presented. For the shear modulus G(n, m), explicit expressions of the extrema (maximum and minimum) and the two mutually orthogonal unit vectors n, m are given for cubic and hexagonal materials. We also present a general procedure for computing the extrema of G(n, m) for more general anisotropic elastic materials. It is shown that Young's modulus E(n) can be made as large as we wish for certain n without assuming that the elastic compliance s11, s22 or s33 is very small. As to the shear modulus G(n,m), it can be made as large as we wish for certain n and m without assuming that any one of the elastic compliance sαβ is very small. We also show that Young's modulus E(n) can be independent of n for orthotropic and hexagonal materials while the shear modulus G(n, m) can be independent of n and m for hexagonal materials.

Relationships between volume plasmon excitations and mechanical properties of various materials are considered. Based on systematic evaluation of available data, correlations between the volume plasmon energy, Ep, Young's modulus, Ym, bulk modulus, Bm, shear modulus, Gm, and microhardness, Hm, are established. The resulting correlations indicate that plasmon energies potentially can be used to predict and/or determine the local mechanical properties of technologically important materials, such as metal alloys, semiconductors, and ceramics at the nanometer level.