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In this study, laser (TruDisk16002)-arc (MAG) hybrid welding was used to weld a 5mm thick sheet of AH36 steel with a gap of 0mm and 1mm. The results show that when the current of MAG is 205A, the voltage is 31.9V, and the laser power is 7.5KW, the welds of 0mm gap and 1mm gap are well formed, showing a typical nail shape, and the 0mm gap weld is better than 1mm. Under the same welding process parameters, the heat-affected zone of a 0mm gap weld is less than 1mm. Upper bainite is found in the 1mm weld gap structure. In the two gap cases, the residual stress on the lower surface is larger than that on the upper surface, and the residual stress in the 1mm weld gap is larger. The weldability of 0mm weld gap is better than 1mm.

In this research, through experiments and numerical simulations, the residual stress distribution of the top and bottom surfaces of the laser (TruDisk16002)-arc (MAG) hybrid welding seam and the weld cross-section are studied. The results show that when the arc power is 6.5KW and the laser power is 7.5KW, the weld is formed well. The residual stress on the bottom surface near the weld is higher than that on the top surface. The laser zone in the center of the weld has the largest residual stress, the arc zone is smaller, and the mixed zone is the smallest. The laser zone has the largest residual stress at the fusion line and the heat-affected zone, followed by the mixed zone, and the arc zone is the smallest. followed by the mixed zone, and the arc zone has the smallest.

In this study, dissimilar butt joints were formed between as-rolled Inconel 718 and SUS 316 using cold metal transfer (CMT) with ERNiFeCr-2 filler metal at a welding speed of 5 mm s−1 and three different welding currents (130, 160 and 190 A). The morphology, microstructure, and mechanical properties of the joints and the mechanism by which the joint interface formed were studied. The results indicate that CMT welding parameters have an effect on the weld appearance and that the weld metal exhibits better wettability and spreadability at a welding current of 160 A. The interface between the weld metal and SUS 316 base metal was characterized by applying an optical microscopy (OM) and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectrometry (EDS). The results revealed that no obvious diffusion of Ni and Fe ions was identified across the joint interface. The fractures that initiated in the joints during the tension testing formed in the heat-affected zone (HAZ) of the SUS 316 base metal, and the high-temperature tensile strength of the joint was observed to be 424 MPa, which is approximately 87.06% of that of SUS 316 base metal (487 MPa) and 67.19% of that of Inconel 718 base metal (631 MPa). In terms of the elongation, the joint (21.9%), Inconel 718 base metal (21.2%) and SUS 316 base metal (22.3%) elongations were similar. For comparison, the joint also was tested at room temperature, resulting in a tensile strength and elongation of 511 MPa and 27.5%, respectively. A spherical elemental Ni segregation morphology was clearly observed at the high-temperature fracture. Hardness studies demonstrated that the weld metal hardness is higher than that of the SUS 316 base metal.

The effects of Climate Change, to include increased droughts, changing animal and plant ranges, and sea level rise, vary from region to region. Many of these effects will alter the national vulnerability. Internationally, we need to set up an evaluation system to characterize the impact of climate on national vulnerability. We identify four elements of the climatic element: precipitation variability, temperature variance, CCPI, natural disasters. We use AHP to set up an evaluation system to identify the direct and indirect impacts of climate. Besides, the degree of vulnerability of a country is automatically identified through neural network mechanism. We use SPSS software to test the model. 178 groups of regression data are obtained from the model and FFP, and the correlation coefficients are 0.95. We apply the model NVS/CNVS to Afghanistan and China. By comparing the two results, we conclude that climate has reduced the vulnerability of Afghanistan by 1.4 percentage points. For China, in considering climate factors, the vulnerability is significantly reduced by 13 percentage points. Finally, we put forward policies and countermeasures for every country to mitigate the impact of climate change on vulnerability.

A novel magnetic g-C3N4 (Fe3O4-g-C3N4) was prepared in one step and used to removal Cd (II) from aqueous solution. VSM, FT-IR, SEM, laser particle analyses and XRD were used to character Fe3O4-g-C3N4. The kinetic data was more descibed by Peseudo-second-order model. Langmuir model to describe isotherms data is more convincing and the predicated maxmium adsorption capacity for Cd (II) is 204.5 mg/g.