Abstract: A high-strength and high-plasticity TWIP steel and a preparation method thereof are disclosed. In the disclosure, comprehensive properties of TWIP steel are improved by inclusion modification with Ce and Ba addition, fine grain strengthening and twinning nanocrystallization; the grain size is controlled by a low-temperature cold rolling, a transient annealing treatment and a low-temperature tempering treatment. Considering the addition of Ce, stacking fault energy of the TWIP steel is reduced, and the formation of twins, and the division of twins into grains are promoted, which further reduces a mean free path of dislocation motion, thereby improving yield strength, and finally obtaining a high-strength and high-plasticity TWIP steel.

Abstract: A high-strength and high-plasticity TWIP steel and a preparation method thereof are disclosed. In the disclosure, comprehensive properties of TWIP steel are improved by inclusion modification with Ce and Ba addition, fine grain strengthening and twinning nanocrystallization; the grain size is controlled by a low-temperature cold rolling, a transient annealing treatment and a low-temperature tempering treatment. Considering the addition of Ce, stacking fault energy of the TWIP steel is reduced, and the formation of twins, and the division of twins into grains are promoted, which further reduces a mean free path of dislocation motion, thereby improving yield strength, and finally obtaining a high-strength and high-plasticity TWIP steel.

Abstract: Provided is a method of forming a roadway by filling gangue paste during wide roadway excavation of a thick coal seam belonging to the technical field of mining industry. The method comprises: firstly designing a width of a filing strip and a width of a new excavation roadway according to a geological condition of a coal seam; secondly, determining a length of each filling, i.e.

Abstract: A method for extracting and recycling chromium from hexavalent chromium-containing residues includes the following steps: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding sodium sulfate, sodium chlorate and sulfuric acid to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; 6) precipitating the supernatant and the water used for washing the filtered residues with a precipitant CaCl2, then centrifugally washing, dewatering and drying the precipitates; and 7) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: A treatment method for resource recycling of hexavalent chromium-containing residues is provided. This method comprises steps as follows: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding mineralizers to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; and the mineralizers are sodium chlorate, sodium perchlorate and hydrochloric acid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; and 6) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: Provided is a method of forming a roadway by filling gangue paste during wide roadway excavation of a thick coal seam belonging to the technical field of mining industry. The method comprises: firstly designing a width of a filing strip and a width of a new excavation roadway according to a geological condition of a coal seam; secondly, determining a length of each filling, i.e.

Abstract: The present invention discloses a treatment method for resource recycling of hexavalent chromium-containing residues, belonging to a field of a clean treatment and resource recycling of chromium-containing residues. This method comprises steps as follows: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding mineralizers to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; and the mineralizers are sodium chlorate, sodium perchlorate and hydrochloric acid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; and 6) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: The present invention discloses a detoxification treatment method for extracting and recycling chromium from hexavalent chromium-containing residues, comprising steps as follows: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding sodium sulfate, sodium chlorate and sulfuric acid to a solution obtained in step 1) and stirring, sufficiently to obtain a mixed liquid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; 6) precipitating the supernatant and the water used for washing the filtered residues with a precipitant CaCl2, then centrifugally washing, dewatering and drying the precipitates; and 7) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.