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Al–Li alloy has been widely used in the aerospace field owing to its high strength and low density. In this study, alternating current cold metal transfer (AC CMT) along with a high-frequency pulse current technique was used to weld a 2060 Al–Li alloy using an ER5356 wire. The effect of pulse frequency on the arc shape, microstructure, and mechanical properties of the welded joints was examined, and mechanical performance testing was conducted. The results revealed that the arc diameter, arc length, and arc volume showed a trend of increasing first and then decreasing with an increase in the pulse frequency and reached their peak values when the pulse frequency was 50 kHz. Coupling the welding process with a high-frequency pulse resulted in grain refinement, which was attributed to the stirring action of the arc force. Both the porosity levels and grain size decreased with increasing frequency. When the pulse frequency was 70 kHz, the porosity level was the lowest, and the grain size was refined to 24.1 μm. The tensile strength of the welded joints also increased with the pulse frequency, and a maximum tensile strength of 249 MPa was observed at 70 kHz.

Textile‐based conductive materials that can retain their electrical conductivity during bending have been extensively investigated and applied in flexible electronics and wearable sensors; however, the fastness of the conductive components in textiles requires improvements. Herein, a facile and effective surface micro‐dissolution method is developed to prepare carbon nanotubes (CNTs)‐coated PET fabric by embedding CNTs onto the surface of PET fabric. The micro‐dissolved layer of the macromolecule served as a physical adhesion agent to firmly immobilize the CNTs on the PET fabric. The CNTs‐coated PET fabric exhibited an electrical conductivity of 98.1 Ω □−1, durability during washing (over 30 cycles) and abrasion cycles (over 500 cycles), and remained conductive in harsh environments (high temperature, high humidity, water, corrosive liquids, organic solvents). The sensor (CCPFS) assembled by the CNTs‐coated PET fabric is flexible (over 500 bending cycles), highly sensitive (1.48 deg−1), responsive (100 ms), and showed a relaxation time of 200 ms. The CCPFS is used to monitor movements in human fingers, wrist, elbow, knee, expiration, breathing, and wrist pulses. This research provides a route to manufacture flexible sensors for next‐generation intelligent wearable devices. [ABSTRACT FROM AUTHOR]

An amorphous Ge-Au(a-Ge-Au) film produced by vacuum deposition was examined in situ and irradiated by an electron beam in a transmission electron microscope. The amorphous Ge-Au film can be crystallized rapidly and locally by electron beam irradiation, forming polycrystalline metastable Ge0.4Aug0.6 tetragonal phase and then decomposing to polycrystalline Ge and polycrystalline Au at increased irradiation dose. Findings showed that the crystallization of a-GeAu film, the formation of Ge0.4Aug0.6 and the decomposition of the metastable Ge0.4Au0.6 are dependent on the temperature of the irradiation process.

Transmission electron microscopic studies of Ge-Au Au bilayer films annealed at several temperatures reveal that the small Au grains coalesce to coarse grains, leading to a fractal structure. Crystallization of amorphous Ge in Ge Au films causes the formation of dense branching fractals. The annealing temperature influences fractal dimension of the patterns formed from the branching fractals.

Presents information on a study which investigated the effects of the disorder of superlattice periods on x-ray diffraction patterns. Calculation of the diffraction profiles of semiconductor superlattices; Effect of systematic deviation of period on the width, position and the shape of superlattice peaks; Explanation of the effects of the local deviation.

Presents a study that examined the thermal stability of multilayer films by use of small-angle x-ray diffraction. List of the films; Temperatures at which the periodicities of multilayers begin to be worse; Temperatures of total mixing of the films.

Presents information on a study which utilized cross-section transmission electron microscopy, selected area electron diffraction and small-angle x-ray diffraction (XRD) to observe the systematic deviations of period in W/Si and W/C multilayers. Experimental procedure; Results and discussion; Process of the XRD method.

Presents a study of fractals in annealed germanium-gold/gold bilayer films. Details of the experiment; Results; Discussion.

Studies the crystallization behavior of a-silicon:hydrogen/silver/a-silicon:hydrogen sandwich films. Details on the experiment; Results of the study; Conclusions.

Presents information on a study which examined the simulation of soft x-ray diffraction behavior of multilayers with sublayer thickness ratio deviation in periods. Method of simulation; Relative diffraction intensities of multilayers; Diffraction intensity.

Presents a simulation of copper (Cu) L∝ and Cu K∝ diffractions from tunsgten/silicon multilayers with a local layer-thickness deviation at various depths of the multilayers. Applications of periodic multilayers; Structure of multilayer with a local stacking fault; Diffraction curves of various local deviation depth.

Investigates the annealing behavior of amorphous germanium bilayer thin films. Applications of amorphous germanium bilayer films; Details on the experiment; Discussion on the results of the study.