•SbSI nanowires prepared sonochemically from Sb2S3 and SbI3 for the first time.•SbSI nanowires used as a filler in electrospun nanofibers for the first time.•PAN/SbSI nanofibers are potentially ...attractive for piezoelectric nanogenerators.
A novel polymeric, polyacrylonitrile (PAN) nanofibers containing ferroelectric and semiconducting antimony sulfoiodide (SbSI) have been made by electrospinning. SbSI nanowires, used as the filler, have been prepared sonochemically from antimony sulphide (Sb2S3) and antimony tri-iodide (SbI3) for the first time. Nanocrystalline SbSI has been fabricated in ethanol under ultrasonic irradiation (20kHz, 565W/cm2) at 323K within 2h. The products have been characterized by using techniques such as powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, high-resolution transmission electron microscopy, selected area electron diffraction and optical diffuse reflection as well as transmission spectroscopy. The good quality of the nanocrystals and their dispersion in the nanofiber’s volume is important because this material is attractive for nanogenerators due to its ferroelectric and piezoelectric properties. The amplitude of the voltage pulse, generated under shock pressure of 3.0MPa, has reached 180V in the prototype PAN/SbSI piezoelectric nanogenerator. The peak output voltage of about 0.2V was measured in bending/releasing conditions with the deformation frequency of 1Hz.
Iron oxide (III) or also known as hematite gained their popularity of material science engineers due to its properties, including photocatalytic activity. Nowadays, some research is being carry out ...to confirm the potential use of Fe2O3 nanomaterials, in particular nanofibers and nanowires in such devices as chemical sensors, magnetic resonances, supercapacitors and transistors. Another important property of hematite is its stability, it has been proved that it is the most durable iron oxide type. Taking into consideration the above, the aim of this work was to produce composite nanofibers with polymer matrix using polyvinylpyrrolidone) with the doping phase of α-Fe2O3 (30% wt.) using combining method of sol-gel technique and electrospinning process. Final fiber mats were characterized by scanning electron microscope (SEM), to determine the influence of iron oxide nanoparticles on the morphology of PVP/hematite nanofibers and UV-Vis spectroscopy to measure the optical properties of nanofibers and determine whether such obtained fibers can be used in manufacturing process of iron oxide (III) crystal nanowires.
This paper presents the study results focused on selected properties of sintered materials used for produce the tool for thermal drilling process (Flowdrill). The studies were carried out on a ...several series of commercial tools of Flat type from dimension 4.5 to 7.3 mm. Microstructure, microhardness, chemical composition as well as surface roughness parameters were investigated. These studies was carried out both before and after drilling processes. On the base of microstructure and chemical composition study, the content of carbides phases and content of porosity in material were determined. Additionally, in the case of tools which have been damaged during the process, the type of fracture was determined. On the fracture surfaces the beach marks were observed, thus confirming that it was fatigue crack. The possibility of applying the Flowdrill technology in industry were also described in this paper.
This paper present the selected properties of coatings produced on steel using for metal forming processes such as forging, extrusion or pressing. For the preparation of surface layers the laser ...cladding with powder technology was applied. The power of laser beam was equal to 550 W and feed rate was 400 mm/min. The aim of presented study was to obtain the microstructure similar to sintered carbide. Microstructure, microhardness, chemical and phase composition as well as corrosion resistance tests were carried out and analysed. It was found that the presence of WC particles in Stellite-6 matrix had a positive influence on mechanical properties, but negative impact on corrosion resistance of produced surface layers in comparison with the unreinforced coating. Using XRD phase analysis, the presence of the hard interstitial phases (WC, W2C, M7C3 and M23C6) in the matrix were confirmed.
The paper presents technology of forming of a face gear cooperating with cylindrical worm in spiroid gear drive application for rotation table. The method is based on application of a disc tool ...instead application of a hob. The solution is possible after application the CNC milling machine with five axis numeric system control. The method of forming face gear proposed in this article is based on application of the disc tool with a single blade edge and CNC milling machine. The method of forming the face gear cooperation with cylindrical worm on CNC milling machine with continuous divide and the scheme of the process kinematics have been presented in the paper.
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