The electrospark deposition (ESD) is a well-known cheap method utilizing concentrated energy flux to transfer a material of an electrode onto the surface of the machined material for enhancing properties of its surface layer. Typically, a hard material of an electrode may be deposited onto the surface of materials with lower hardness to make such an object more robust for wearing. Coatings produced by ESD may be applied to protect new elements or to recover the properties of worn elements. Unfortunately, ESD process produces a surface with high roughness. The laser beam machining (LBM) has been involved to lower roughness of the coating made by ESD. The elements coated by ESD have been tested to determine tribological properties and they were compared before and after LBM. To achieve high reliability of the results, the test has been conducted in accordance with design of experiments (DoE) methodology and the results which were obtained have been processed by a statistical analysis. The description of such an experiment performed for a silicon carbide SiC coating, the obtained results and the conclusions are included in this paper.

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The electron beam additive manufacturing (EBAM) method was applied in order to fabricate rectangular-shaped NiTi component. The process was performed using an electron beam welding system using wire feeder inside the vacuum chamber. NiTi wire containing 50.97 at.% Ni and showing martensitic transformation near room temperature was used. It allowed to obtain a good quality material consisting of columnar grains elongated into the built direction growing directly from the NiTi substrate, which is related to the epitaxial grain growth mechanism. As manufactured material showed martensitic and reverse transformations diffused over the temperature range from −10 to 44 °C, the applied aging at 500° C moved the transformation to higher temperatures and transformation peaks became sharper. The highest recoverable strain of about 3.5% was obtained in the as-deposited sample deformed along the deposition direction. In the case of deformation of the alloy aged at 500 °C for 2h, the formation of martensite occurs at significantly lower stress; however, at about 2.5% the stress begins to increase gradually and only a small shape recovery was observed due to a higher martensitic transformation temperature. In situ SEM tensile deformation in the direction perpendicular to deposition direction showed that the martensite began to appear at the surface of the sample and at the grain boundaries due to heterogeneous nucleation. In situ studies allowed to determine the following crystallographic relationships between B2 and B19’ martensite: (100)B2||(100)B19’ and (100) B2 || (011)B19’; (011)B2|| (001)B19’ and $${(011)}_{\mathrm{B}2}||{\left(11\bar{1 }\right)}_{\mathrm{B}1{9}^{\mathrm{^{\prime}}}}$$ ( 011 ) B 2 | | 11 1 ¯ B 1 9 ′ . Samples aged at 500 °C exhibited fully austenitic microstructure; however, with increasing degree of deformation, the formation of martensite was observed. The majority of needles were tilted about 45° with respect to the tensile direction, and the presence of type I (11 $$\bar{1 }$$ 1 ¯ ) invariant twin boundaries was observed at higher degrees of deformation.

Contribution presents results of study of tribological characteristics of Fe-Zn coated steel sheets. Experimental research was done using coatings with different alloying -under alloyed, optimal and slightly pre alloyed. The optimally alloyed coatings and the slightly prealloyed ones were annealed in order to reach different alloying level. Alloying level was evaluated by phase composition and % Fe in coating. Tribological properties such as surface microgeometry, abrasion, friction coefficient were analysed from the view of formability. Experimental results of strip drawn test were used for verification of strip-drawn test numerical simulation. Based on numerical simulation results, contact pressure on drawing die radius was observed.Keywords: Fe-Zn coatings, steel sheets, coating morphology, friction coefficient, numerical simulation IntroductionCurrent production in the automotive, consumer goods industry and also other industries must adapt to many; often mutually conflicting technical, economic and environmental requirements. On the one hand, customer demands for products performance, primarily for safety, reliability, corrosion resistance, driving dynamics, comfort and economy are growing; on the other hand, pressure to reduce emissions, higher productivity, eco-friendly production, reduction of maintenance costs and prices of products is increasing. The main innovative trends for increasing the performance of automobiles include reducing the weight of structural parts that contribute the most to the total weight of the car (body 26 %, 23 % undercarriage, motor 21 %, 22 % equipment, etc.). The effectiveness of this approach has been demonstrated by the results of the project ULSAB. For more than 80% of structural elements of the ULSAB body the builders have used high-strength steels with yield strength from 210 to 550 MPa, ultra-high strength steels with yield strength above 550 MPa, almost half of the weight of the body consists of laser-welded tailored blanks (tailored blanks) and sandwich materials [1,2]. In order to ensure the adequate lifetime of autobodies, majority of structural elements of ULSAB body are made of zinc coated sheets. Among the coated steel sheets are given the ratio between quality and the price of its irreplaceable galvanized sheets. During annealing after galvanization the transformation of the

The effect of using two different deposition systems on the microstructure and mechanical properties was studied in this paper. For this purpose, laser-engineered net shaping (LENS) and high-power CO2 laser deposition processes were applied to fabricate Inconel 625 samples. The microstructure of the Inconel 625 produced by both additive techniques was characterized using light microscopy (LM), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). The mechanical properties were characterized by tensile tests and microhardness measurements. High-power laser application resulted in a strong <100> build texture, while, at low powers, the {011} <100> Goss component increased. Both types of deposited materials showed dendritic microstructures with Ti-, Mo-, and Nb-rich zones at the cell boundaries, where numerous precipitates (Nb2C, NbC, titanium carbides, Nb3Ni, and NbNiCr) were also observed. It was also noted that both variants were characterized by the same slope with a proportional length, but the Inconel 625 fabricated via LENS showed a higher average yield strength (YS; 524 MPa vs. 472 MPa) and ultimate tensile strength (UTS; 944 MPa vs. 868 MPa) and lower elongation (35% vs. 42%) than samples obtained with the high-power CO2 laser deposition process.