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The paper is concerned with determining the influence of laser treatment process on the properties of electro spark coatings. The properties were assessed after a laser treatment by analysing microstructure and X-ray diffraction and measuring surface geometric structure and microhardness. The studies were conducted using WC-Cu electrodes produced by powder metallurgy of nanostructural powders. The coatings were deposited by means of the EIL-8A model and they were laser-treated with the Nd:YAG, BLS 720 model.

This overview presents a comprehensive exploration of the research methods employed for the precise assessment of volume fraction and the detailed characterisation of the size, shape and distribution of γ’ phase precipitates within Ni-based superalloys. These advanced materials exhibit exceptional mechanical properties due to the presence of γ’ precipitates. The accurate quantification of precipitate parameters is crucial for understanding material behaviour and for the optimisation of alloy design. In this overview, a spectrum of techniques, including microscopy (SEM, TEM), diffraction (XRD), spectroscopy (EDS, EELS) and advanced imaging (3D-APT, STEM-HAADF, FIB-SEM) is discussed. Strengths, limitations and potential synergies among these methods are highlighted, offering researchers a comprehensive toolbox to advance their investigations of γ’ phase precipitates in Ni-based superalloys.

This overview presents a comprehensive exploration of the research methods employed for the precise assessment of volume fraction and the detailed characterisation of the size, shape and distribution of γ’ phase precipitates within Ni-based superalloys. These advanced materials exhibit exceptional mechanical properties due to the presence of γ’ precipitates. The accurate quantification of precipitate parameters is crucial for understanding material behaviour and for the optimisation of alloy design. In this overview, a spectrum of techniques, including microscopy (SEM, TEM), diffraction (XRD), spectroscopy (EDS, EELS) and advanced imaging (3D-APT, STEM-HAADF, FIB-SEM) is discussed. Strengths, limitations and potential synergies among these methods are highlighted, offering researchers a comprehensive toolbox to advance their investigations of γ’ phase precipitates in Ni-based superalloys.

The paper presents the results of the investigations of welded joints of the tube-flat bar type made of SA213 T12 and SA387Gr11CL2 steels. The joints were produced in two variants: 1) with heating up to 200°C, 2) without heating. The materials were joined by the submerged arc welding method. The temperatures of preheating before welding were determined, and it was verified whether the empiric relations (1) and (2), used to determine the minimal temperature of heating before welding for steel, can be applied under production conditions. The produced welded joints were evaluated quality-wise. Hardness measurements were performed in the particular joint areas. Finally, the effect of preheating on the obtained joints was compared.

The heat-treatment processes for the precipitation-strengthened nickel-based superalloys are extremely complicated. The solution heat treatments are designed to dissolve the gamma-prime and the secondary carbide phases and allow the optimum re-precipitation of these phases upon cooling or after aging, for various precipitation-strengthened superalloys. The study was conducted to examine the effects of two solutionizing heat treatments on the microstructure of the CMSX4 superalloy. A comparison between the two obtained microstructures was performed.

The analysis of variance (ANOVA) is a classic tool for an identification of discreet factors impact on the measurable output by a specific decomposition on a total variance according to the scheme proposed by R.A Fisher in the 1920s. There are many explicit and implicit assumptions required as a preliminary of ANOVA computations. The ANOVA computations scheme is well known and implemented in many types of software but all estimations are provided with the assumption of a normal and homoscedasticity distribution of the noise disturbing the output. Computation procedures produce a single number output (e.g. F statistics, p-Value) without any analysis of their own dispersion. This paper analyzes the ANOVA output using the bootstrap approach. It seems to be the most convenient as a data-driven procedure. The source raw data are taken from the image analysis conducted during the investigation of the impact of the ceramic layer thickness on the wax pattern assembly of a turbine blade on the (γ+γ’) eutectic in the IN713C superalloy.

Surrogate models are very useful to replace very accurate but time-consuming huge data numerical models. The process of construction and optimization of surrogate models may require large computational power. It may be delivered by multi-core CPU or by massively multi-core GPGPU. This paper presents a consistent approach to make quantitative assessment of the computational efficiency with different hardware configurations: with one and multi-core CPU and with GPGPU card. The design of experiments factorial approach is used to analysis of the obtained data. The linear main effects model with two-way interaction is identified. The results show that the investment to multi-core CPU and GPGPU cards simultaneously is impractical due to negligible effects of CPU efficiency which is masked by dominated GPGPU performance.

The paper is concerned with the performance properties of electrospark deposited coatings. The properties were assessed by analyzing the coating microstructure, X-ray diffraction, microhardness, roughness and bonding strength.The studies were conducted using WC-Co-Al2O3 electrodes produced by sintering nanostructural powders. The anti-wear coatings were electro-spark deposited over C45 carbon steel by means of an EIL-8A. These coatings are likely to be applied to increase the abrasive wear resistance of tools and machine parts.

The main aim of the undertaken research was to evaluate the state of the material of V degree live steam superheater pipe coils made of 10CrMo9-10 (10H2M) chromium-molybdenum steel as well as to determine their usability for further operation. The pipe coils came from a steam boiler working at a power plant. The scope of the research included: a literature analysis of the issue, an elaboration of the research plan, cutting and preparing the test samples, microstructural tests with the use of a light microscope, microstructural tests performed by means of a scanning electron microscope and conclusion drawing on the basis of the performed tests and the literature review. The work presents the steels of which the mentioned elements were made as well as analyzes their working conditions. It describes the most often observed causes of pipe coil damage and presents techniques of controlling the proper efficiency and usability of these elements for further operation.

The aim of the work is estimation of usefulness of several selected etchants and image acquisition methods for revealing of microstructure of CMSX-4 nickel–based superalloy from computer-aided quantitative metallography’s point of view. The analysis was carried out on images registered using light and scanning electron microscopes. The images of the microstructure have been analyzed in γ γ’ eutectic’s investigations context, especially to estimate the eutectic quantitatively. The work contains description of experimental method for quantitative evaluation of γ γ’ eutectic present in as-cast state of the superalloy. A quantitative evaluation of γ γ’ eutectic islands in CMSX 4 superalloy is indispensable for a proper evaluation of γ’ phase precipitates. It is mainly related to coarse cellular γ’ phase precipitates present in γ γ’ eutectic islands.

The purpose of the research was to illustrate a reconstruction of grains in case of selected cross-section of a precision cast turbine blade made of MAR M247 polycrystalline nickel-base superalloy using electron backscatter diffraction (EBSD) in the scanning electron microscope (SEM) and standard methods of quantitative metallography using imaging with light microscopy. The results of measurement of the grains performed using both methods were compared with each other with the help of a statistical test.