Characteristics of CuCrTiAl alloy after plastic deformation

The development of the automotive industry leads to the search for newer construction materials, but also those used in the production process. Although many types of joints are used in vehicles, resistance welds remain the dominant one. The commonly used alloy for welding caps (CuCrZr) is already well known and therefore newer alloys and technologies for their production are sought to increase service life, and thus reduce production costs. Precipitation hardening CuCrTiAl alloy was analysed in this article. After casting, CuCrTiAl alloy was subjected to cold and hot deformation and then tested for its usability. The obtained results confirmed the potential of this alloy to make electrodes for resistance welding

The influence of plasma nitriding on the microstructure of X153CrMoV12 and X165CrV12 steels

This study presents the results of research into the influence of the time of the plasma nitriding process on the microstructure of the coatings obtained on cold-work tool steels X153CrMoV12 and X165CrV12. The processes were carried out under industrial conditions using an Ionit system (Oerlikon Metaplas) with variable process times of 2, 4 and 6 hours. Nitriding mixture consisting of 5 % nitrogen and 95 % hydrogen was chosen, which allowed the expected diffusion layer to be obtained without a white layer (composed of iron nitrides). Analysis of relative elemental concentrations indicates that the presence and content of nitride-forming elements influences the formation of alloy additive nitrides in the microstructure of the diffusion layer. Nitrides of alloying additives, present in the diffusion layer, indicating that investigated steels are the most suitable for plasma nitriding

Characteristics of CuCrTiAl alloy after plastic deformation

The development of the automotive industry leads to the search for newer construction materials, but also those used in the production process. Although many types of joints are used in vehicles, resistance welds remain the dominant one. The commonly used alloy for welding caps (CuCrZr) is already well known and therefore newer alloys and technologies for their production are sought to increase service life, and thus reduce production costs. Precipitation hardening CuCrTiAl alloy was analysed in this article. After casting, CuCrTiAl alloy was subjected to cold and hot deformation and then tested for its usability. The obtained results confirmed the potential of this alloy to make electrodes for resistance welding

The influence of plasma nitriding on the microstructure of X153CrMoV12 and X165CrV12 steels

This study presents the results of research into the influence of the time of the plasma nitriding process on the microstructure of the coatings obtained on cold-work tool steels X153CrMoV12 and X165CrV12. The processes were carried out under industrial conditions using an Ionit system (Oerlikon Metaplas) with variable process times of 2, 4 and 6 hours. Nitriding mixture consisting of 5 % nitrogen and 95 % hydrogen was chosen, which allowed the expected diffusion layer to be obtained without a white layer (composed of iron nitrides). Analysis of relative elemental concentrations indicates that the presence and content of nitride-forming elements influences the formation of alloy additive nitrides in the microstructure of the diffusion layer. Nitrides of alloying additives, present in the diffusion layer, indicating that investigated steels are the most suitable for plasma nitriding

Influence of the speed of downward semi-continuous casting on the crystal size and mechanical properties of recycled copper

In this study, the influence of the speed of downward semi-continuous casting on the crystal size and mechanical properties of recycled copper after casting and cold deformation was investigated. It was shown that the increase in the casting speed from 0,09 m / min to 0,22 m / min resulted in refinement of the macrostructure and reduction of the crystal cross-sectional area from 3,221 mm2 to 1,2 mm2, which resulted in an increase in microhardness after casting by 8 %, while in the state after cold working, an increase in microhardness by 3 % and ultimate tensile strength by 2,5 %

Influence of the speed of downward semi-continuous casting on the crystal size and mechanical properties of recycled copper

In this study, the influence of the speed of downward semi-continuous casting on the crystal size and mechanical properties of recycled copper after casting and cold deformation was investigated. It was shown that the increase in the casting speed from 0,09 m / min to 0,22 m / min resulted in refinement of the macrostructure and reduction of the crystal cross-sectional area from 3,221 mm2 to 1,2 mm2, which resulted in an increase in microhardness after casting by 8 %, while in the state after cold working, an increase in microhardness by 3 % and ultimate tensile strength by 2,5 %

The effect of the rolling process on selected properties of magnesium copper with microadditives

The article presents the results of rolling magnesium copper castings with microadditives of P, Al, Ti, and Zr. The castings were made in the process of static casting into rods with a diameter of 20 mm. The obtained castings were shaped with a 3 % draft into bars of square cross-section and rolled on a shape mill with 20 % drafts on average. Mechanical properties were determined in a static tensile test at selected degrees of plastic deformation (57,2 %, 76,9 % and 91,3 %). At the final stage of cold working of the wire rods with a total draft of 91,3 %, the microstructure and electrical conductivity were examined. The research indicates a strong influence of microadditives on the strengthening of castings in the rolling process and their electrical conductivity

The effect of the rolling process on selected properties of magnesium copper with microadditives

The article presents the results of rolling magnesium copper castings with microadditives of P, Al, Ti, and Zr. The castings were made in the process of static casting into rods with a diameter of 20 mm. The obtained castings were shaped with a 3 % draft into bars of square cross-section and rolled on a shape mill with 20 % drafts on average. Mechanical properties were determined in a static tensile test at selected degrees of plastic deformation (57,2 %, 76,9 % and 91,3 %). At the final stage of cold working of the wire rods with a total draft of 91,3 %, the microstructure and electrical conductivity were examined. The research indicates a strong influence of microadditives on the strengthening of castings in the rolling process and their electrical conductivity

Influence of structure on soft magnetic properties of Co 70Fe 5Si 15B 10 metallic glass ribbons

Purpose: The paper presents a structural, thermal and magnetic characterization of Co-based amorphous samples in as-cast state and after annealing process. Design/methodology/approach: The studies were performed on Co70Fe5Si15B10 metallic glass in form of ribbons with different thickness. The amorphous structure and phase analysis of studied samples after annealing process was examined by X-ray diffraction (XRD). The crystallization behaviour of the studied ribbons was also examined by differential scanning calorimetry (DSC). The fracture morphology of the ribbons after heat treatment was analysed using the scanning electron microscopy (SEM). The soft magnetic properties examination contained relative initial magnetic permeability and magnetic permeability relaxation measurements. Findings: The X-ray diffraction investigations revealed that the tested ribbons with different thickness were amorphous. The two exothermic peaks describing crystallization process of Co70Fe5Si15B10 alloy were observed for all studied samples with different thickness. The heat treatment process of ribbon samples involved crystallization of α-Co(Si), Co2Si phases and cobalt borides at temperature above 773 K. The study of fracture morphology of samples after annealing at 623 K shows mixed fractures with “river” patterns, which are characteristic for glassy materials and some areas of scaly morphology. The initial magnetic permeability decreases in function of the increase of annealing temperature, but a local maximum could be determine at 673 K. Practical implications: The soft magnetic properties of studied metallic glasses can be formed by different sample thickness and applying the appropriate conditions of annealing process. Originality/value: The applied investigation methods are suitable to determine the changes of structure and soft magnetic properties of examined Co-based alloy with function of sample thickness and heat treatment conditions

Optical, Dielectric and Magnetic Properties of La1−xNdxFeO3 Powders and Ceramics

Nanocrystalline La1−xNdxFeO3 powders with different concentrations of Nd3+ have been synthesized using a modified Pechini method. Their structures were studied by X-ray powder diffraction (XRD). Furthermore, La1−xNdxFeO3 nanoceramics were prepared using a high pressure sintering technique. The luminescence spectra of the powders were investigated as a function of concentration of active dopant to check the possible energy transfers observed due to Nd3+ concentration changes. The electrical and magnetic properties of the powders and ceramics were investigated to determine the effect of Nd3+ doping on the dielectric permittivity and magnetization in the wide frequency range. © 2018 by the authors. Licensee MDPI, Basel, Switzerland.Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 778070—TransFerr—H2020-MSCA-RISE-2017. Part of the work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement