Considering the number of deaths due to air pollution, it is clear that it poses a great danger to public health. Sources that cause air pollution can be divided into two groups: natural resources (such as desert storms, fires and volcanic eruptions) and artificial sources (residences, industrial sector and motor vehicles), which cause a much higher rate of air pollution than natural resources. It is known that air pollutants originating from ships and port operations have an important share among vehicle sourced pollutants. Considering the emissions from both ships and operational reasons and their proximity to human habitats, it is obvious that port regions are important points in terms of emissions harmful to human health. The use of cold-ironing technology in ports instead of providing the energy needed from ship auxiliary machinery during the hotelling period at the port is the most effective method used to reduce the amount of ship-sourced emissions in the port area. On the other hand, it is seen that the number of ports where cold-ironing technology is used, which is extremely effective in reducing emissions harmful to human health, is quite limited. In this context, the share of the emission amount during the hotelling period in the total emission amount in the port area was calculated according to ship type and duration of hotelling in the port, and the importance of the use of cold-ironing technology in reducing the port-originated emissions was emphasized.

A low carbon structural steel was surface-hardened by friction stir processing (FSP) through 4 mm thickness from the surface. The hardness of the alloy increased from 140 Hv0.1 to about 240 Hv0.1 after single-pass FSP. This improvement came from the substantial microstructural refinement due to both severe plastic deformation and dynamic recrystallization. Both yield and tensile strength of the alloy increased without a considerable decrease in ductility after FSP. Friction and wear behavior of the alloy before and after FSP was investigated by a pin-on-disk type tribometer according to ASTM-G133. The substantial increase in both hardness and yield strength resulted in a considerable improvement in wear resistance of the alloy depending on applied pressure. In this study, metallurgical and mechanical reasons for such improvement in wear behavior and any change in wear mechanisms after FSP were investigated.

Copper (Cu) is widely used in electrical, electronic, and tribological systems owing to its excellent electrical and thermal conductivity. However, its relatively low hardness and poor wear resistance limit its use in demanding engineering applications. In this study, Cu-based hybrid metal matrix composites (MMCs) reinforced with hexagonal boron nitride (h-BN) and boron carbide (B₄C) were fabricated via spark plasma sintering (SPS) to improve their mechanical and tribological performance. The h-BN content was fixed at 1 wt.% to ensure solid lubrication, while the B₄C content was varied (0.25, 0.5, 0.75, and 1 wt.%) to examine its influence on the microstructural, mechanical, electrical, and wear properties of the composites. Microstructural analyses confirmed a homogeneous distribution of h-BN and B₄C particles in the Cu matrix at low and moderate reinforcement levels, whereas excessive B₄C resulted in partial agglomeration and reduced densification. All composites achieved relative densities above 95%, demonstrating the high densification efficiency of the SPS process. Hardness increased markedly with B₄C addition due to dispersion strengthening and grain refinement, while electrical conductivity decreased slightly because of the insulating nature of the reinforcements. Tribological tests showed that the composite containing 0.75 wt.% B₄C exhibited the best performance, with the lowest wear rate and stable friction behavior. Overall, the results indicate that co-reinforcing Cu with h-BN and B₄C through SPS is a promising strategy for developing multifunctional materials suitable for electrical contact and sliding applications.