53results about How to "Uniform grain size distribution" patented technology

The invention discloses a method for producing an iron-zinc alloy coated steel plate with the yield strength being equal to or higher than 220 MPa. The method comprises the steps that molten iron desulphurization, smelting through a converter and continuous casting are conducted, so that a billet is formed; hot rolling is conducted; rolling is conducted; cold rolling is conducted till the billet reaches the required thickness; continuous hot galvanizing is conducted; rapid cooling is conducted; aerial fog is used for cooling after zinc and iron are alloyed; finishing is conducted; oiling treatment is conducted; and sampling, performance testing and subsequence procedure treatment are conducted. According to the method for producing the iron-zinc alloy coated steel plate with the yield strength being equal to or higher than 220 MPa, on the premise that the yield strength ranges from 220 MPa to 260 MPa, the tensile strength ranges from 300 MPa to 380 MPa, and the elongation is equal to or higher than 43%, grains on the surface of a zinc-iron alloy coating are fine and are even in size distribution, the area ratio of holes in the surface of the coating is equal to or smaller than 5%, no microcrack exists on the surface, and the phenomena of pulverization and falling of the coating are unlikely to occur during stamping forming, namely the 90-degree V bending test grade reaches the level 2.

The invention belongs to the technical field of chemical catalysts, and specifically relates to a preparation method of a hierarchical pore heteroatom aluminum phosphate molecular sieve for oxidativedesulfurization. The method comprises the following steps: synthesizing a microporous aluminum phosphate molecular sieve through a dynamic hydrothermal crystallization manner; and preparing the hierarchical pore heteroatom aluminum phosphate molecular sieve in a mesoporous template agent and metal source synthesizing system by taking the prepared microporous aluminum phosphate molecular sieve as aseed crystal. According to the method, the synthesizing time is reduced; the prepared molecular sieve is controllable and uniform in crystal particles; and the desulfurization effect is high in catalytic oxidative desulfurization reaction.

The invention is a preparing method of a zinc-oxide varistor composite powder and a zinc-oxide varistor composite additive powder, comprising the steps of: (1) mixing according to the formulation, (2)liquid phase coprecipitation, (3) filtering and washing, (4) adding antimony tartrate or colloidal antimony oxide, (5) drying and calcining, and (6) screen separating. In steps (1) and (2), the saltsolutions of the component are uniformly mixed and liquid phase coprecipitated, ensuring the uniformity of the zinc-oxide varistor composite powder. The coprecipitation agent is NaOH or Na2CO3, the coprecipitation promoter is NH4OH. In step (2), the mixed solution of the coprecipitation agent and the coprecipitation promoter is added to a reaction system, so that each component can be combined instantaneously under the same process condition. The method can produce a zinc-oxide varistor composite powder and a zinc-oxide varistor composite additive powder which have a granularity of less than 1mum, narrow granularity distribution scope, uniform components and impurity of no more than 0.01%.

The invention discloses a method for preparing a metal material, comprising: horizontally placing the metal material to be prepared between the concave mold and the wave surface of the convex mold, the press is connected with the convex mold, and the convex mold is used to press the The metal material is pressed so that the metal material is in full contact with the male die and the concave die, and the pressed metal material is ejected and turned horizontally and then placed in the wave of the female die and the male die. Between the surfaces, repeat the pressing and turning process until the strain accumulation of the metal material meets the requirements, and then take out the deformed metal material after being flattened by a plane mold. The invention can prepare large-sized nanomaterials; the structure refinement ability is stronger, the deformation is more uniform, and the processing process is simpler; macroscopic texture defects do not occur, and nanomaterials with uniform and isotropic grain size distribution can be obtained.