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This article presents cyclic hardening/softening behaviors (experimental data) of the heat-treated aluminum-matrix nano-clay-composite (AlSi_N_HT6), compared to those of the piston aluminum alloy (AlSi) under strain-controlled loading. For such an objective, standard samples were fabricated by gravity and stir-casting methods. Low-cycle fatigue experiments were carried out under different strain amplitudes (0.20–0.45%) and at various temperatures (25–300°C). Obtained results implied that no obvious change was observed on material properties of aluminum alloy by reinforcements, but a decrement was observed due to increasing the temperature. Results also indicated that the increase of the temperature from 25°C to 200°C has changed the cyclic behavior of both materials (AlSi_N_HT6 and AlSi) from hardening to softening. Moreover, the temperature effect was more significant than the total strain amplitude influences in cyclic behaviors.

Digital image correlation (DIC) techniques were used to evaluate strain distributions along tensile gage lengths immediately after yielding of a medium manganese steel (7 wt% Mn) in samples cold rolled in the range of 1–6 pct. With an increase in cold work, DIC confirmed that the yielding behavior transitioned from nucleation and propagation of a single localized deformation zone (Lüders band) to uniform deformation, that is, no evidence of strain localization. At intermediate amounts of cold work, a unique yielding behavior was evident where the initially-low positive strain hardening rate increased with tensile strain until conventional strain hardening (i.e., decrease in strain hardening rate with strain). The intermediate yielding behavior was associated with the development of multiple non‑propagating regions of strain localization, an observation not previously evident without the use of DIC.

Philippine natural bentonite is characterized using X-ray diffractometer (XRD), scanning electron microscope (SEM), chemical analysis, thermogravimetric-differential scanning calorimetry (TG-DSC), and Fourier transform infrared (FTIR) analysis. The cation exchange capacity (CEC) was also measured. XRD shows that the mineral is composed primarily of mordenite, hectorite, and montmorillonite. SEM shows the flaky and porous structure of the bentonite powder. Chemical analyses show that SiO2 (47.90 wt%) and Al2O3 (14.02 wt%) are the major components of the clay. TG-DSC shows that the mineral contains 15.55% moisture. IR transmittance spectrum shows the common vibration bands present in the sample which include O–H stretching of inter-porous water, symmetric and asymmetric stretching of hydroxyl functional groups, asymmetrical stretching of internal tetrahedra (O–Si–O and O–Al–O), symmetrical stretching of external linkages, and so on. The measured CEC were found to be 91.37 and 43.01 meq/100 g according to the ammonium acetate method and barium acetate method, respectively.