Research,application and development of inorganic binder for casting process

Inorganic binder used in casting process has the advantages of low odor,labor-friendly conditions,and relatively low cost,which is one of the main development directions for casting molding materials in the future.However,compared to organic binders(such as resin binders),inorganic binders exhibit lower bonding strength and are more sensitive to environmental humidity.This sensitivity poses challenges,particularly in the reclamation of used sand,thus limiting their broader application.In this paper,the research and application status of inorganic binders(mainly silicate inorganic binders)and their curing methods are summarized.In addition,the research and application of phosphate inorganic binders and 3D printing inorganic binders that are being developed are introduced.Meanwhile,a detailed comparative analysis is conducted on the challenging issue of“reclamation for used sand”in the application of inorganic binders.Finally,the development direction of inorganic binders is clarified.

Recycling water glass from wet reclamation sewage of waste sodium silicate-bonded sand

Wet reclamation of waste sodium silicate-bonded sand produces much alkaline sewage and causes pollution. Recycling water glass from wet reclamation sewage of the waste sodium silicate-bonded sand can solve pollution issues and generate economic benefits. In this work, the wet reclamation sewage was filtered, and the filtrate was causticized with a quicklime powder to produce a lye. The effects of causticization temperature, causticization time, and the amount of quicklime powder on the causticization rate were studied. The lye was used to dissolve the silica in the filtration residue to prepare a sodium silicate solution. The effects of the mass of filtration residue, dissolution temperature, and dissolution time on sodium silicate modulus were studied. Finally, the recycled water glass was obtained by concentrating the sodium silicate solution, and the bonding strength of the recycled water glass was tested. The results showed that the causticization rate could be improved by increasing the amount of quicklime powder, causticization temperature, and causticization time, and the highest causticization rate was above 92%. Amorphous silica in the filtration residue dissolved in the lye. Increasing the amount of the filtration residue, dissolution temperature, and dissolution time could improve the sodium silicate modulus. The bonding strength of the recycled water glass was close to that of commercial water glass. The recycled water glass could be used as a substitute for the commercial water glass.

Relativistic motion on Gaussian quantum steering for two-mode localized Gaussian states

Realistic quantum systems always exhibit gravitational and relativistic features.In this paper,we investigate the properties of Gaussian steering and its asymmetry by the localized two-mode Gaussian quantum states,instead of the traditional single-mode approximation method in the relativistic setting.We find that the one-side Gaussian quantum steering will monotonically decrease with increasing observers of acceleration.Meanwhile,our results also reveal the interesting behavior of the Gaussian steering asymmetry,which increases for a specific range of accelerated parameter and then gradually approaches to a finite value.Such finding is well consistent and explained by the well-known Unruh effect,which could significantly destroy the one-side Gaussian quantum steering.Finally,our results could also be applied to the dynamical studies of Gaussian steering between the Earth and satellites,since the effects of acceleration are equal to the effects of gravity according to the equivalence principle.