Ductile iron is a high-strength cast iron material. The spherical graphite obtained by inoculation treatment effectively improves the mechanical properties of cast iron, resulting in higher strength than carbon steel. However, severe corrosion may occur under specific circumstances, especially in thermal water pipelines. In this paper, the corrosion mechanisms at the main defective points of ductile iron were investigated using microscopic morphological characterization after accelerated tests combined with numerical simulations. The influence law of each environmental factor on the corrosion kinetics of ductile iron in a complex water quality environment was studied using dynamic potential polarization tests. The results showed that the main causative factors leading to the increased corrosion of ductile iron were the presence of tail-like gaps on its surface, and the crescent-shaped shrinkage and loosening organization around the graphite spheres. After mechanical treatment was applied to eliminate the obvious defects, the number of corrosion pits was reduced by 41.6%, and the depth of the pits was slowed down by 40% after five days. By comparison, after ten days, the number of pits was reduced by 51%, and the depth of the pits was slowed down by 50%. The dynamic potential polarization test results show that the dissolved oxygen concentration has the greatest influence on the corrosion of ductile iron in the simulated water environment; meanwhile, the water hardness can slow down the corrosion of ductile iron. The relative influence of each environmental factor is as follows: dissolved oxygen concentration > temperature > immersion time > water hardness > pH > Cl⁻.

The effect of final thermomechanical treatment (FTMT) on the mechanical properties and microstructure of a T-Mg₃₂(Al Zn)₄₉ phase precipitation hardened Al-5.8Mg-4.5Zn-0.5Cu alloy was studied. The as-cold rolled aluminum alloy samples were subjected sequentially to solid solution treatment, pre-deformation, and two-stage aging treatment. Vickers hardness was measured during the aging process under various parameters. Tensile tests were conducted on the representative samples based on the hardness results. Microstructural characteristics were analyzed via transmission electron microscopy and high-resolution transmission electron microscopy. The conventional T6 process was also carried out for comparison. The hardness and tensile strength are increased evidently by the FTMT process for the Al-Mg-Zn-Cu alloy, while the ductility is adversely affected to a small extent. The precipitation at the T6 state consists of a coherent Guinier–Preston zone and T″ phase in the form of intragranular, fine, and spherical particles, while a semi-coherent T′ phase appears after the FTMT process as a new constituent. The distribution of dislocation tangles and isolated dislocations is another feature of FTMT samples. Enhanced precipitation hardening and dislocation strengthening account for the improved mechanical performance of FTMT samples.

The flexible transparent conductive films (TCFs) of a ZnS/Cu/Ag/TiO₂ multilayered structure were deposited on a flexible PET substrate with high surface roughness using magnetic sputtering, and the effects of structural characteristics on the performance of the films were analyzed. The TCFs with TiO₂/Cu/Ag/TiO₂ and ZnS/Cu/Ag/ZnS symmetric structures were also prepared for comparison. The TCF samples were deposited using ZnS, TiO₂, Cu and Ag targets, and they were analyzed using scanning electronic microscopy, atomic force microscopy, grazing incidence X-ray diffraction, spectrophotometry and a four-probe tester. The TCFs exhibit generally uniform surface morphology, excellent light transmittance and electrical conductivity with optimized structure. The optimal values are 84.40%, 5.52 Ω/sq and 33.19 × 10⁻³ Ω⁻¹ for the transmittance, sheet resistance and figure of merit, respectively, in the visible spectrum. The satisfactory properties of the asymmetric multilayered TCF deposited on a rough-surface substrate should be mainly attributed to the optimized structure parameters and reasonable interfacial compatibilities.

The structural, optical and electrical properties of the flexible, asymmetric TiO₂/Cu/Ag/ZnS and ZnS/Cu/Ag/TiO₂ transparent conductive films (TCFs) were studied. The multilayered TCFs were magnetron sputtered onto the flexible PET substrate layer-wise, with TiO₂, ZnS, Cu and Ag targets. The atomic force microscope, scanning electronic microscope, X-ray diffractometer, ultraviolet-visible spectrophotometer and four-probe tester were utilized to characterize the samples. The photoelectric property of the multilayers varies with the adjustment in structural parameters. The ZnS/Cu/Ag/TiO₂ samples demonstrate a more uniform surface morphology and better optical and electrical properties than the TiO₂/Cu/Ag/ZnS counterparts. The optimal sheet resistance and average transmittance of the ZnS/Cu/Ag/TiO₂ films are 5.56 Ω/sq and 88.46% in the visible spectrum, with the corresponding figure of merit reaching 52.76 × 10⁻³ Ω⁻¹. The bottom ZnS layer reveals superior percolation function for the bimetallic layer, forming with good continuity and homogeneity, although the original surface roughness is higher than that of TiO₂. The top TiO₂ layer demonstrates a smooth morphology and dense structure, beneficial to the high transparency and stability of the multilayer.

Theoretical calculations were performed to explore the heterogeneous nucleation mechanism of an Mg-Al alloy inoculated by a carbon-containing substance. The valence electron structure and cohesive energy of Al₄C₃ and Al₂C₂Mg crystals were calculated using the empirical electron theory of solids and molecules (EET). The binding energy of Al1-C2 bonds in Al₄C₃ is about 140.6 kJ/mol with a lower number of equivalent bonds. Correspondingly, the binding energy of Al2-C2 bonds is about 129.6 kJ/mol, and the number of equivalent bonds is high. The weak combination of the Al1 and C2 atomic layers might lead to the breaking of Al₄C₃, and then the remaining strong skeleton of the Al2-C2 structure will facilitate the formation of Al₂C₂Mg. Based on the calculating results, the atomic interaction mechanism to account for the heterogeneous nucleation of α-Mg by C inoculation is elaborated, which also provides insights into the essence of the overheating process and the influence of Al and Mn elements on the refinement efficiency of Al₂C₂Mg.