The field of metal additive manufacturing has witnessed significant growth in recent years, with technology offering the ability to produce complex geometries that are challenging to manufacture using the traditional methods. In situ monitoring and control of the manufacturing process are crucial for increasing the production capacity and improving the quality of manufactured parts. This article provides a comparative analysis of computational, indirect, and direct methods for in situ temperature monitoring during additive manufacturing of metal alloy components. Furthermore, it discusses the current status, recent improvements, and perspectives for in situ temperature measurements. The basic principles of thermal imaging, two-color pyrometry, and millimeter-wave radiometry are explored, highlighting their limitations for addressing challenges related to material emissivity and rapid changes in building material composition. Overcoming the challenges related to the inaccessibility of the chamber where the parts are formed, direct temperature measurements would allow for the integration of collected information into big data systems. Within the framework of Industry 4.0, this approach offers a viable alternative to the conventional metal shaping processes, improving the production capacity and part quality. This research aims to contribute to ongoing advancements in metal additive manufacturing and its potential to completely replace traditional metal casting practices in the Industry 4.0 era.

Advancements in computer capabilities enable predicting process outcomes that earlier could only be assessed after post-process analyses. In aerospace and automotive industries it is important to predict parts properties before their formation from liquid alloys. In this work, the logistic function was used to predict the evaporation rates of the most detrimental impurities, if the temperature of the liquid aluminum alloy was known. Then, parameters of the logistic function were used to determine the transition points where the reaction order was changing. Samples were heated to 610 °C, 660 °C, 710 °C, and 760 °C for one hour, after which the chemical analyses were performed and evaporation rates were calculated for Cd, Hg, Pb and Zn elements. The pressure inside the encapsulated area was maintained at 0.97 kPa. Whereas parameters that define the evaporation rate increase with the temperature increase, the maximum evaporation rates were deduced from the experimental data and fitted into the logistic function. The elemental evaporation in liquid-aluminum alloys is the best defined by the logistic function, since transitions from the first to zero-order-governed evaporation reactions have nonsymmetrical evaporation rate slopes between the lowest and the highest evaporation rate point.

Reducing the costs of repairing concrete structures damaged due to the appearance of cracks and reducing the number of people involved in the process of their repair is the subject of a multitude of experimental studies. Special emphasis should be placed on research involving industrial by-products, the disposal of which has a negative environmental impact, as is the case in the research presented in this paper. The basic idea was to prepare a mortar with added granulated blast furnace slag from Smederevo Steel Mill and then treat artificially produced cracks with a Sporosarcina pasteurii DSM 33 suspension under the conditions of both sterile demineralized water and water from the Danube river in order to simulate natural conditions. The results show a bio-stimulated healing efficiency of 32.02% in sterile demineralized water and 42.74% in Danube river water already after 14 days. The SEM images clearly show calcium carbonate crystals as the main compound that has started to fill the crack, and the crystals are much more developed under the Danube river water conditions. As a special type of research, microscopic images of cracks were classified into those with and without the presence of bacterial culture. By applying convolutional neural networks (ResNet 50), the classification success rate was 91.55%.

Remediating and recovering valuable metals from metallurgical slags is a critical challenge and opportunity for sustainable resource management in the metal extraction industry. This study investigates a process to simultaneously recover nickel, copper, and cobalt from nickel converter slag from the Sudbury region, Canada, using carbon- and iron-based reducing agents. Experimental results show that, without additives, performing reduction settling at 1300 °C, a process similar to metal extraction from ore concentrates, yielded 62 wt% recovery of valuable metals, while after adding reducing additives, over 90% of entrained valuable metals were efficiently coalesced into a matte phase within one hour, significantly reducing the hazardous metal content in the residual slag leaving mainly iron and silicon oxides, which are stable and environmentally benign. X-ray diffraction and SEM-EDS analyses show that after treatment, the dominant phases in the residual slag are fayalite (Fe₂SiO₄) and glassy silicates, with almost no detectable sulfide or metallic inclusions or other leachable metal-bearing phases. Estimated total cost to increase and maintain slag temperature at 1300 °C for 1 h is $44.50 per tonne. The exothermic reaction of ferrosilicon with slag provides 14.60 kWh/tonne of energy, reducing the need for external heating, while the value of recovered metals is about 10 times higher than the estimated capital, processing, and transportation costs of the additional process treatment. An efficient and sustainable approach to recovering valuable metals from nickel slag, using innovative chemistry and process integration, delivered high metal recovery, reduced environmental impact, and clear economic benefits. The proposed approach aligns with the United Nations Sustainable Development Goals, as outlined in the document ‘Transforming Our World: the 2030 Agenda’, supports circular economy principles, enhances resource efficiency, and offers a practical pathway for remediating legacy slag deposits in existing metals extraction facilities.

Reducing the costs of repairing concrete structures damaged due to the appearance of cracks and reducing the number of people involved in the process of their repair is the subject of a multitude of experimental studies. Special emphasis should be placed on research involving industrial by-products, the disposal of which has a negative environmental impact, as is the case in the research presented in this paper. The basic idea was to prepare a mortar with added granulated blast furnace slag from Smederevo Steel Mill and then treat artificialy produced cracks with a Sporosarcina pasteurii DSM 33 suspension under the conditions of sterile demineralized and water from Danube river in order to simulate natural conditions. The results show a bio-stimulated healing efficiency of 32.02% in sterile demineralized water and 42.74% in Danube water already after 14 days. The SEM images clearly show calcium carbonate crystals as the main compound that has started to fill the crack, and the crystals are much more developed under the Danube water conditions. As a special type of research, microscopic images of cracks were classified into those with and without the presence of bacterial culture. By applying convolutional neural networks (ResNet 50), the classification success rate was 91.55%.

The implementation of measures and activities aimed at preserving the environment is preceded by the categorization of products created by the application of technological processes. The emission of harmful substances within the limit prescribed values is defined by the valid legislation of the Republic of Serbia. The development of project documentation for the disposal of ash, slag and gypsum from the technological process of flue gas desulphurization (FGD) must be based on the application of modern technologies in order to preserve the surrounding ecosystem. The planning of the landfill space for the accommodation of combustion and desulfurization products requires the analysis of all input parameters of the technological process of electricity production. The use of ash, slag and gypsum as products of the production process of thermal power plants is not adequately accepted in the domestic industry. The role of new technologies should be directed towards the greatest possible utilization of stored products in order to produce new products, thus preserving mineral resources and protecting the conditions of the living environment.