Experience in conducting tests on a torsiometer to determine the pitch of the metal cord

Hardware production is in continuous improvement: the requirements imposed by consumers stimulate the introduction of new technological solutions and equipment. For metal products produced by hardware shops (metal cord, wire for RVD, side bronzed wire), mechanical properties are important, which determine the strength, ductility and other characteristics of materials. Metal cord has a number of physical and chemical characteristics: the diameter of the metal cord, lay pitch, linear density, deviation from straightness, residual torsion, untwistability, characteristics of the brass coating-chemical composition – coating weight, brass thickness, adhesion, mechanical properties-breaking load, elongation at break.The article describes the procedure for measuring the size of the lay pitch on a torsiometer installed by Metro Com engineering S. p. A., Italy using an upgraded device with ten pulses (resolution of the turn counter = 0.1 rotation of the rotating clamp). Comparative tests of 2x0. 30NT metal cord samples taken from a single coil were performed using a device with a resolution of 0.25 turns and 0.1 turns of the rotating clamp of the installation to determine the pitch of the coil

The influence of the characteristics of breaking test units on the results of testing plastic properties of the wire RML

For metal products manufactured by hardware shops (metal cord, PML wire and side bronzed wire), the most important mechanical properties are those, that determine the strength, ductility and other characteristics of the materials. The article describes the characteristics of breaking test unit that affect the results of tests of plastic properties of RML wire. The analysis of the test conditions and factors affecting the test results was made

Thermal Decomposition of Polystyrene in the High Temperature Fabrication Technology of Hollow Microspheres

The degree and nature of polymer degradation that occurs in the high temperature microshell formation process developed at the Lebedev Physical Institute has been examined experimentally. We find that significant mass degradation occurs during the final stages of shell formation. This manifests itself both in terms of mass loss and molecular weight degradation as measured by gel permeation chromatography. This decrease in the molecular weight may be in part responsible for the relatively fragile nature of the shells produced by this high temperature process. 9 refs., 6 figs., 2 tabs

Thermal decomposition of polystyrene in the high temperature fabrication technology of hollow microspheres. Revision 1

The degree and nature of polymer degradation that occurs in the high temperature microshell formation process developed at the Lebedev Physical Institute has been examined experimentally. We find that significant mass degradation occurs during the final stages of shell formation. This manifests itself both in terms of mass loss and molecular weight degradation as measured by gel permeation chromatography. This decrease in the molecular weight may be in part responsible for the relatively fragile nature of the shells produced by this high temperature process. 9 refs., 6 figs., 2 tabs

Measuring of spatio-temporal characteristics Z-pinch from deuterated polyethylene

On the S-300 installation at currents up to 2 MA with rise time 100 ns, the investigation of the formation process of high-temperature plasma in fast Z-pinch was carried out. The central part of the loads was made from agar-agar and represented a deuterated polyethylene cylinder with small density 50 and 75 mg/sm3 and 1–2 mm diameter. On the ICT images, obtained in optical and soft X-ray range of a spectrum with 3–5 ns exposition, it is visible that on the axis of the polyethylene cylinder at the current`s rise time a cord is formed and it is separated into bright formations. They were observed on a background of a luminous area which occupied the initial neck volume. On time-integrated pinhole pictures obtained in SXR range (E > 1–4 keV), hot points with minimal size of 50 microns were registered. From the chronograms results, obtained by means of the optical high-speed-streak camera mount along the neck axis with time resolution 1 keV with short duration of 2–4 ns. Simultaneously with X-ray radiation neutrons with the maximal yield of 4.5×109 were registered. The average energy measured in 4 directions under angles with an axis of: 0○ (above the anode), 90○, 180○ (under the cathode) and 270○, were accordingly: 2.4±0.2, 2.5±0.1, 2.5±0.1, 2.5±0.1 MeV