In this paper the surfaces of some steel samples, low alloyed, were covered by electric arc thermal spray with a steel layer, high alloyed, containing FeNiCrSiB-WC/TiC, using a core wire. In order to study the influence of process parameters on obtained deposits, the surface roughness and the intensity of electric current varied on three levels and the rest of the technological parameters were kept constant. The microstructural characteristics, chemical composition, physical and mechanical properties of the obtained deposits were investigated by SEM analysis of microhardness and by X-ray diffraction. The deposition porosity was investigated by optical microscopy. The adhesion of the layers was investigated by the traction test. Studies have shown that by increasing the intensity of the electric current respectively the arc temperature, the deposition porosity decreases by 23,4%, the microhardness HV and the adherence of the samples subjected to the test increases. The FeNiCrSiB-WC/TiC layers, deposited on low alloyed steel support, can be considered as convenient solutions for obtaining hard, wear-resistant surfaces.

European legislation stipulates the obligation to carry out a risk assessment for each job, as well as the application of measures to prevent these occupational risks. Therefore, taking into account the importance of risk determination at the workplace for the prevention of work accidents and occupational diseases, this paper proposes the digitization of a risk assessment method. The application of the occupational injury and illness risk assessment method begins with a document that contains a description of the company (name, location, domain of activity, organization chart, etc.), a description of the work system detailing its components and a brief description of the assessment method. Next follows a Microsoft Excel document that performs the actual application of the method. Finally, another document presents the list of measures that lead to the implementation of the prevention and protection plan. This paper presents the code design of the Microsoft Excel document, an essential part in the application of the method of assessing the risks of occupational injury and illness. The document is structured on a variable number of worksheets, which present the different types of occupational injury and illness based on risks on the components of a work system. The digitalization of the risk assessment method reduces the time allocated to the evaluation without affecting its quality.

The physical and mechanical properties of the coatings produced by electric arc thermal spraying are closely related to the velocity and temperature of the particles that interact with the substrate surface. Knowing the temperature variation of the sprayed particles allows establishing their aggregation state, respectively determining the spraying distance, so that the state of aggregation of the particles at the impact moment is predominantly liquid. Obviously, when the sprayed particle passes through the spray cone, it cools continuously due to the low and variable temperature of the entrainment gas. This paper aims to determine analytically the thermal behavior of the particles entrained by the gas jet formed at the thermal spraying in an electric arc, depending on the variable temperature, existing along the spraying cone. In this sense, by modeling with finite elements, using the ANSYS program, the temperature inside the spray jet was determined, and by a mathematical model carried out based on the thermal balance equations, the thermal profile of the sprayed particles was determined. The thermal profile demonstrates that their temperature suddenly increases to the solidification temperature, then increases to the melting temperature—due to the latent heat of solidification, after which it decreases to 300 K.

The offenses concerning safety and health at work have no material object, their constitutive content including: the object and subject of the offense, the objective and subjective side of the offense. The active subjects of an offense have a legal obligation to apply and control the implementation of occupational safety and health measures and the passive subjects will bear the consequences of the occurrence of specific events. The existence of some uncertainties in the current legislation, also affecting mining companies, creates legal disputes especially in relation to the issues concerning active subjects. As for the passive subjects, the legal loophole refers to the situation of the day-labourers who may be involved in accidents at work and occupational illnesses. The authors consider it is necessary to formulate new law articles for clarification and even to draw up a future law with concrete reference to day-labourers, but also to some new risk sensitive social groups. Thus, the egal work relationships: the manner of performing the work, its remuneration and subordination to the beneficiary carrying out mining activities, will also be specified.

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