Search

The xSrTiO3-(1−x)NaPO3 (x = 0−0.20 mol%) glasses were prepared by the conventional melt-quenching method. The amorphous state of the samples was verified by X-ray diffraction. The glass-ceramic materials were obtained by the well known thermal controlled crystallization process. It is found that several physical properties such as the density, molar volume, and the glass transition temperature depend strongly on the chemical composition. Vickers test on the glasses showed that the micro-hardness increases with the SrTiO3 content. The structural approach of the glasses was realized by IR spectroscopy. This technique has highlighted the co-existence of different phosphate and titanium structural units in the glassy-matrix. Crystallization of the glasses was enhanced by heat treatments and followed by X-ray diffraction. A mechanism for this glass crystallization was proposed.

In this study, we tried to understand the texture evolution of deformation during the cold drawing of copper wire (99.26%) Drawn by the company ENICAB destined for electrical cabling and understand its link with the electrical conductivity. Characterisations performed show the appearance and texture development during the reduction of section of the wire. The texture is mainly composed of the fiber // DN (DN // drawing axis) (majority) and the fiber // ND (minority) whose acuity increases with deformation level. The wire was performed for the main components of the texture, ie the fiber and conventionally present in these materials. We will pay particular attention on the energy of the cube component {100} recrystallization that develops when the level of reduction is sufficient. There was also an increase in hardness and electrical resistivity along the applied deformation.

The use of modern pulsed-arc welding technologies allows a significant improvement of the quality of welded joints. However, a large number of possible welding modes hinder the development and implementation of pulse technologies in modern production. This is associated with the fact that in pulsed-arc welding at least four independently variable parameters exist, which in totality requires a large number of experiments to determine their impact. To optimize the number of experiments in this study, the experimental calculation Taguchi algorithm for the process of pulsating arc welding using a high alloy welding material was implemented. The quantitative contribution of each variable welding parameter in the formation of the penetration depth is shown. The optimal welding modes were proposed, providing a set penetration depth. 15 Ref., 6 Tables, 4 Figures. [ABSTRACT FROM AUTHOR]

The use of modern pulse-arc welding technologies allows a signifi cant improvement of the quality of welded joints. However, a large number of possible welding modes hinder the development and implementation of pulse technologies in modern production. This is associated with the fact that in pulsed arc welding at least four independently variable parameters exist, which in totality requires a large number of experiments to determine their impact. To optimize the number of experiments in this study, the experimental calculation Taguchi algorithm for the process of pulsating arc welding using a highly alloy welding material was implemented. The quantitative contribution of each variable welding parameter in the formation of the penetration depth is shown. The optimal welding modes were proposed, providing a set penetration depth. 15 Ref., 6 Tabl., 4 Fig. [ABSTRACT FROM AUTHOR]

Pulsed-arc welding is characterized by a periodical changing in arc power and, due to its features, it allows solving complex technological problems while creating unique structures, increasing efficiency of welding processes while maintaining a high level of physical and mechanical properties of welded joints. There are many manufacturers of welding equipment, that introduced the idea of using pulsed welding in their production, but data on the impact of pulsed-arc welding on parameters of welds have a different nature. For the successful application of pulsed-arc welding in modern production, it became necessary to study the influence of pulsed-arc welding conditions on the parameters of welds and HAZ as compared to welding using stationary-burning arc, performed using low-alloy welding materials. 20 Ref., 7 Figures. [ABSTRACT FROM AUTHOR]

Pulsed-arc welding is characterized by a periodical changing in arc power and, due to its features, allows solving complex technological problems while creating unique structures, increasing efficiency of welding processes while maintaining a high level of physical and mechanical properties of welded joints. There are many manufacturers of welding equipment, that introduced the idea of using pulsed welding in their production, but data on the impact of pulsed-arc welding on the parameters of the welds differ. For the successful application of pulsed-arc welding in modern production, it became necessary to study the influence of pulsed-arc welding conditions on the parameters of welds and HAZ as compared to stationary welding using burning arc, made of low-alloy welding materials. [ABSTRACT FROM AUTHOR]

The precipitation of nano-sized Cr clusters was investigated in a commercial Cu-1Cr-0.1Zr (wt.%) alloy processed by equal-channel angular pressing and subsequent aging at 550°C for 4 h using Small-Angle Neutron Scattering (SANS) measurements and High-Angle Annular Dark-Field-Scanning Transmission Electron Microscopy (HAADF-STEM). The size and volume fraction of the nano-sized Cr clusters were estimated using both techniques. The parameter values assessed by SANS (d ~ 3.2 nm, Fv ~ 1.1 %) agreed reasonably with those by HAADF-STEM (d ~ 2.5 nm, Fv ~ 2.3 %). In addition to the nano-sized Cr clusters, HAADF-STEM indicated the presence of rare cuboid and spheroid sub-micronic Cr particles measuring approximately 380-620 nm in mean size. Both techniques did not evidence the presence of intermetallic CuxZry phases within the aging conditions. [ABSTRACT FROM AUTHOR]