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Studies on the determinants of low-carbon innovations in developed countries already exist. We test here the institutional environment in Poland (science–government–enterprise) as supporters of the technological change in industry towards a low-carbon economy. We will examine as well whether conclusions for well-developed countries are relevant for those catching up. The aim of the article is to assess the systemic nature and durability of the impact of internal and external conditions on the implementation of low-carbon technologies in Polish industry. In order to achieve the goal, two surveys were carried out for the periods 2007–2012 and 2013–2018, on sample sizes of 11,493 enterprises. To verify the hypotheses, a statistical multi–factor logit modelling was used to determine the chances of low-carbon innovations under the influence of various parallel circumstances. The results of this research point to other, often abrupt (unstable) phenomena occurring in the catching-up economy, which are the consequence of a long-term technological gap. The case of Poland shows the lack of cooperation between science, enterprises and the government in stimulating the development of low-carbon technologies, although enterprises do try to implement such technologies on their own in the absence of any external cooperation. Without Research and Development (R&D) support and government subsidies, the attempt to implement low-carbon technology fails. Thus, the institutional framework should distinguish between catching-up and developed countries due to the gaps in technological knowledge, cooperation and institutional barriers.

In the current study, a 2 mm thick low-carbon steel sheet (A283M—Grade C) was joined with a brass sheet (CuZn40) of 1 mm thickness using friction stir spot welding (FSSW). Different welding parameters including rotational speeds of 1000, 1250, and 1500 rpm, and dwell times of 5, 10, 20, and 30 s were applied to explore the effective range of parameters to have FSSW joints with high load-carrying capacity. The joint quality of the friction stir spot-welded (FSSWed) dissimilar materials was evaluated via visual examination, tensile lap shear test, hardness test, and macro- and microstructural investigation using SEM. Moreover, EDS analysis was applied to examine the mixing at the interfaces of the dissimilar materials. Heat input calculation for the FSSW of steel–brass was found to be linearly proportional with the number of revolutions per spot joint, with maximum heat input obtained of 11 kJ at the number of revolutions of 500. The temperature measurement during FSSW showed agreement with the heat input dependence on the number of revolution. However, at the same revolutions of 500, it was found that the higher rotation speed of 1500 rpm resulted in higher temperature of 583 °C compared to 535 °C at rotation speed of 1000 rpm. This implies the significant effect for the rotation speed in the increase of temperature. The macro investigations of the friction stir spot-welded joints transverse sections showed sound joints at the different investigated parameters with significant joint ligament between the steel and brass. FSSW of steel/brass joints with a number of revolutions ranging between 250 to 500 revolutions per spot at appropriate tool speed range (1000–1500 rpm) produces joints with high load-carrying capacity from 4 kN to 7.5 kN. The hardness showed an increase in the carbon steel (lower sheet) with maximum of 248 HV and an increase of brass hardness at mixed interface between brass and steel with significant reduction in the stir zone hardness. Microstructural investigation of the joint zone showed mechanical mixing between steel and brass with the steel extruded from the lower sheet into the upper brass sheet.

The emerging technology of wire arc additive manufacturing (WAAM) has been enthusiastically embraced in recent years mainly by the welding community to fabricate various grades of structural materials. In this study, ER70S-6 low-carbon low-alloy steel wall was manufactured by WAAM method, utilizing a gas metal arc welding (GMAW) torch translated by a six-axis robotic arm, and employing advanced surface tension transfer (STT) mode. The dominant microstructure of the fabricated part contained randomly oriented fine polygonal ferrite and a low-volume fraction of lamellar pearlite as the primary micro-constituents. Additionally, a small content of bainite and acicular ferrite were also detected along the melt-pool boundaries, where the material undergoes a faster cooling rate during solidification in comparison with the center of the melt pool. Mechanical properties of the part, studied at different orientations relative to the building direction, revealed a comparable tensile strength along the deposition (horizontal) direction and the building (vertical) direction of the fabricated part (~ 400 MPa and ~ 500 MPa for the yield and ultimate tensile strengths, respectively). However, the obtained plastic tensile strain at failure along the horizontal direction was nearly three times higher than that of the vertical direction, implying some extent of anisotropy in ductility. The reduced ductility of the part along the building direction was associated with the higher density of the interpass regions and the melt-pool boundaries in the vertical direction, containing heat-affected zones with coarser grain structure, brittle martensite–austenite constituent, and possibly a higher density of discontinuities.

Ductile-to-brittle transition (DBT) temperature and brittle fracture stress, σF, are important toughness criteria for structural materials. In this paper, low-carbon steels with an ultrafine elongated grain (UFEG) structure (transverse grain size 1.2 μm) and with two ferrite (α)-pearlite structure with grain sizes 10 µm and 18 µm were prepared. The UFEG steel was fabricated using multipass warm biaxial rolling. The tensile tests with a cylindrical specimen and three-point bending tests with a single-edge-notched specimen were performed at −196 °C. The local stress near the notch was quantitatively calculated via finite element analysis (FEA). The σF for each sample was quantified based on the experimental results and FEA. The relationship between σF and dα in the wide range of 1.0 μm to 138 μm was plotted, including data from past literature. Finally, the conditions of grain size and temperature that cause DBT fracture in low-carbon steel were shown via the stress−d−1/2 map. The results quantitatively showed the superiority of α grain size for brittle fracture.

Excessive carbon emissions have posed a threat to sustainable development. An appropriate market-based low carbon policy becomes the essence of regulating strategy for reducing carbon emissions in the energy sector. This study proposes a Stackelberg game-theoretic model to determine an optimal low carbon policy design in energy market. To encourage fuel switching to low-carbon generating sources, the effects of varying carbon price on generator's profit are evaluated. Meanwhile, to reduce carbon emissions caused by energy consumption, carbon tracing and billing incentive methods for consumers are proposed. The efficiency of low carbon policy is ensured through maximising social welfare and the overall carbon reductions from economic and environmental perspectives. A bi-level multiobjective optimisation immune algorithm is designed to dynamically find optimal policy decisions in the leader level, and optimal generation and consumption decisions in the followers level. Case studies demonstrate that the designed model leads to better carbon mitigation and social welfare in the energy market. The proposed methodology can save up to 26.41% of carbon emissions from the consumption side for the UK power sector and promote 31.45% of more electricity generation from renewable energy sources.

The use of fossil fuels as the main source of energy for most countries has caused several negative environmental impacts, such as global warming and air pollution. Air pollution causes many health problems, causing social and economic negative effects. Worldwide efforts are being made to avoid global warming consequences through the establishment of international agreements that then lead to local policies adapted to the development of each signing nation. In addition, there is a depletion of nonrenewable resources which may be scarce or nonexistent in future generations. The preservation of resources, which is a common goal of the Circular Economy strategy and of sustainable development, is not being accomplished nowadays. In this work, the calculation of indicators and mathematical and statistical analysis were applied to clarify and evidence the trends, provide information for the decision-making process, and increase public awareness. The fact that European countries do not possess abundant reserves of fossil fuels will not change, but the results of this analysis can evolve in the future. In this work, fossil fuel energy consumption, fossil fuel depletion, and their relationship with other variables, such as energy dependence and share of renewable energy in gross final energy consumption, were analyzed for 29 European countries. Furthermore, it was possible to conclude that many European countries still depend heavily on fossil fuels. Significant differences were not found in what concerns gross inland consumption per capita when the Kruskal–Wallis test was applied. It was possible to estimate that by 2050 (considering Jazz scenario) it will only remain approximately 14% of oil proven reserves, 72% of coal proven reserves and 18% of gas proven reserves. Given the small reserves of European countries on fossil fuels, if they need to use them, they will fast disappear.

Purpose Wire + arc additive manufacturing (WAAM) uses existing welding technology to make a part from metal deposited in an almost net shape. WAAM is flexible in that it can use multiple materials successively or simultaneously during the manufacturing of a single component. Design/methodology/approach In this work, a gas metal arc welding (GMAW) based wire + arc additive manufacturing (WAAM) system has been developed to use two material successively and fabricate bimetallic additively manufactured structure (BAMS) of low carbon steel and AISI 316L stainless steel (SS). Findings The interface shows two distinctive zones of LCS and SS deposits without any weld defects. The hardness profile shows a sudden increase of hardness at the interface, which is attributed to the migration of chromium from the SS. The tensile test results show that the bimetallic specimens failed at the LCS side, as LCS has lower strength of the materials used. Originality/value The microstructural features and mechanical properties are studied in-depth with special emphasis on the bimetallic interface.

This paper presents the changes in microstructure and mechanical properties that occurred across the wall cross-section of a massive slag ladle casting due to service conditions. The slag ladle was made of low-carbon cast steel. Based on the test results, it was shown that the working environment influenced the macro-segregation of C and S on the cross-section of the wall and, consequently, had an effect on the changes in microstructure. A pearlitic–ferritic microstructure was found in the central part, while in the outer and inner parts of the wall, the microstructure was of a ferritic–pearlitic type. This change mainly influenced the impact energy—the lowest values were obtained at the centre of the wall (24 J at +20 °C). In the remaining areas tested on the wall cross-section at +20 °C, the impact energy exceeded the minimum required value of 27 J in the Charpy test. The tests revealed the presence of a network of cracks in areas adjacent to the inner surface of the ladle wall, which had a negative impact on the impact energy values, as did the presence of non-metallic inclusions. The changes found in the microstructure as a result of the ladle operation caused significant differences in properties such as impact energy and hardness, while also affecting, though to a lesser extent, the mechanical properties (UTS = 397–434 MPa; YS = 222–236 MPa).

Steel processing requires energy-efficient heat-treatment routes without compromising material performance. Traditional annealing furnaces used for low-carbon (LC) steels are energy-intensive and major contributors to CO2 emissions, creating a need for sustainable alternatives. This study evaluates continuous electric furnace (CEF) annealing as a low-emission route to tailor the microstructure, texture, and mechanical properties of cold-rolled LC steel. Samples were annealed at 750 °C and 850 °C for 60 s, followed by comprehensive microstructural and crystallographic characterization using XRD, SEM, EBSD (IPF, GOS, KAM, ODF), hardness, and tensile testing. Annealing increased recrystallization from ~4% in the as-rolled condition to ~98% at 850 °C, reduced the mean KAM from 1.9° to 0.1°, enhanced the high-angle grain boundary fraction to 0.91, and promoted γ-fiber strengthening while suppressing detrimental θ-fiber components. The 850 °C condition achieved optimal mechanical performance (UTS × TE = 11.1 GPa%). These results demonstrate that CEF annealing enables sustainable processing with better mechanical performance in LC steels.

Low-carbon travel has emerged as a topic of interest in tourism and academia. Studies have offered reasons tourists may engage in low-carbon travel; however, these explanations are scattered throughout the literature and have yet to be integrated into low-carbon travel motivation and constraint constructs. This study develops a low-carbon travel motivation scale (LCTMS) and a low-carbon travel constraint scale (LCTCS). It performs reliability and validity testing to measure the low-carbon travel motives and obstacles. Items were collected primarily by literature review, and, then, by surveys of 382 tourists from low-carbon travel destinations and 390 from non-low-carbon travel destinations. Through a rigorous scale development process, this study identifies six dimensions of the LCTMS (environmental protection, experience-seeking, escape or social connection, industry pleas and measures for environmental protection, low-carbon products, and green transportation) and four dimensions of the LCTCS (intrapersonal constraints, interpersonal constraints, structural constraints, and the not a travel option).