33results about How to "Achieve isotropy" patented technology

The invention is related to the foundry practice. According to this invention, the method for making castings by directed solidification from a selected point of the melt toward the periphery of the casting comprises forming a casting in a mold having thermodynamic characteristics that allow uniform volume cooling of the melt to be effected to a temperature at which natural solidification processes are completed. To improve the structural isotropy of the casting formed, the cooling is effected at a rate not exceeding 0.5° C. / sec. The casting is formed in a nonuniform field of force. The nonuniform field of force is set up by ultrasonic waves focused on a selected point of the melt to form therein a localized elevated pressure zone and to direct the solidification front from the zone toward the periphery of the casting. The nonuniform field of force is sustained in the mold until the cooling casting reaches a temperature at which the natural melt solidification processes are completed as the melt cools. Before the melt is poured into the mold, it is overheated to a level that, together with the thermodynamic characteristics of the mold allowing the melt therein to be cooled at a rate not exceeding 0.5 K / sec, sustains the liquid phase of the melt for a time sufficient for directed melt solidification to be effected from the selected point of the melt toward the periphery of the casting before the commencement of natural melt solidification processes as the melt cools. Subsequently, as the temperature at which natural solidification processes are completed is reached, the nonuniform field of force is removed, and casting cooling may continue at any reasonable rate.

The invention provides a porous material structure having negative Poisson's ratios in partial directions. The porous material structure comprises a multi-layered network structure which is sequentially stacked in parallel along the Z-axis direction, the adjacent upper and lower network structures are connected by a support ligament and each layer of the network structure extends along the XOY plane. The porous material structure eliminates the tensile-shear coupling effect of the two-dimensional substructure on the XOY plane during deformation, so that the constitutive relationship of the three-dimensional structure is normally orthogonal under normal conditions so that design and analysis are convenient. By adjusting the geometrical dimensions, the structure can not only achieve isotropy, but also has a large change range of Poisson's ratios in three directions so that the choice of practical applications is increased.

The invention discloses a chiral auxetic superstructure material structure with tension-torsion coupling characteristics and a preparation method thereof, which includes a plurality of three-dimensional unit cell structures, each three-dimensional unit cell structure includes two polygonal ring structures arranged up and down, the upper and lower The vertices of the two polygonal ring structures are respectively connected by correspondingly arranged inclined cylinders, and the plurality of inclined cylinders are arranged in dislocation along the same direction, and the vertices of the two polygonal ring structures are respectively provided with connection points for connecting adjacent three-dimensional unit cell structures. Rods, several three-dimensional unit cell structures are arranged in a spatial array, connected by corresponding connecting rods to form a chiral auxetic metamaterial structure with tension-torsion coupling characteristics.

The invention relates to a method for preparing an isotropic ceramic nanowire prefabricated body. The polymer precursor is loaded on activated carbon powder to form a mixture and pressed into a blank template, so that the polymer precursor on the template is cracked at a certain temperature. A large number of cross-overlapped nanowires are grown. The active carbon is then oxidized to remove, and an isotropic interconnected three-dimensional network structure ceramic nanowire prefabricated material is prepared. The nanowires in the isotropic ceramic nanowire prefabricated body prepared by the invention have pure composition, uniform structure, controllable size and adjustable volume fraction. The process steps are simple, the cycle is short, the cost is relatively low, and the process also has good stability and repeatability. At the same time, the ceramic nanowire prefabricated body has functions such as heat insulation, light weight, electricity, and optics, and is expected to meet the requirements of multifunctional integration and expand the application field of ceramic matrix composite materials.

The invention discloses an in-plane quasi-isotropic structure-stealthy composite material and further comprises a preparation method of the in-plane quasi-isotropic structure-stealthy composite material. The in-plane quasi-isotropic structure-stealthy composite material comprises a base body and a reinforcement body which are composited and solidified through a VARTM process. The base body is madeof resin; the reinforcement body is made of sandwich-type three-dimensional stereo woven material, the woven material is composed of a plurality of mutually-parallel fiber layers and normal fibers perpendicular to the fiber layers, and the fiber layers are bound together by the normal fibers through a weaving method. The preparation method specifically comprises the following steps of 1, weavingof the reinforcement body; 2, reinforcement body moulding; 3, glue injecting and solidifying; and 4, demoulding. The problems that as for a stealthy composite material in the prior art, the electromagnetic property is isotropic, the anti-impact property is poor, and the stealthy composite material is likely to be layered after being impacted are solved.

The invention relates to a designable layered structure of oblique yarns in a plane, which has multiple layers, and each layer is composed of warp yarns and oblique yarns, wherein the warp yarns are distributed in a sinusoidal form along the length direction of the fabric; Extend forward or reverse spirally along the length direction at a certain angle with the warp yarns, and interweave with the warp yarns, the aforementioned included angle is an acute angle; while the oblique yarns interweave with the warp yarns of the current layer, they also interweave with the warp yarns of the adjacent layer. The invention can improve the in-plane isotropic performance, facilitate the realization of mechanized preparation, and can better meet the requirements of fabric uniformity, integrity, high damage tolerance, impact resistance, delamination resistance and fatigue resistance, and has good uniformity and performance Excellent, easy to operate, conducive to mechanized preparation, high efficiency and low cost. The present invention can be applied to the molding of plate-shaped fabrics, and can also be applied to the molding of rotary-shaped fabrics such as cylindrical, conical, and special-shaped fabrics.

The invention discloses a group of three-dimensional hollow porous structures with isotropic properties. The group of structures includes five different three-dimensional hollow porous structures, which are respectively generated by IWP type, Gyroid type, Primitive type, Dimond type and S-type minimal curved surfaces. isotropic hollow porous structure. The present invention obtains the topological configuration of the three-dimensional hollow porous structure under different volume fractions by performing Boolean operations on the minimum surface structure with specific parameters, and the obtained three-dimensional porous structure has isotropic properties, and is a three-dimensional isotropic porous structure The design provides a reference and has certain application prospects in the fields of lightweight, load bearing, energy absorption and impact resistance.

A fiber-optic three-dimensional trigger probe device and measurement method, the device includes a light source, an optical fiber measuring rod, an elastic reset mechanism, a measuring ball coated with a reflective film, and a photoelectric detection unit, the optical fiber measuring rod has a central optical fiber and 4N receiving optical fibers coaxially and uniformly distributed around the central optical fiber, N is a positive integer, and the elastic reset mechanism is arranged between the optical fiber measuring rod and the measuring ball to reset the measuring ball to In the initial position, the light source emits constant power light and is transmitted to the measuring ball through the central optical fiber, and the light reflected by the reflective film is transmitted to the photoelectric detection unit through the receiving optical fiber. The device can overcome the measurement error caused by the force deformation of the measuring rod during detection, and has high resolution and measurement accuracy at the same time.

The invention provides a method for preparing a billet for a medicine-shaped cover, which sequentially performs multi-directional reciprocating and ultra-low temperature large-deformation extrusion; the multi-directional reciprocating upsetting extrusion is sequentially performed on three faces of the six-sided billet with the same apex Reciprocating upsetting extrusion, single extrusion ratio ≥ 1.5, complete 2 to 4 cycles of multi-directional reciprocating upsetting extrusion; the ultra-low temperature and large deformation extrusion is to subject the billet to cryogenic treatment for 60 to 150 minutes, and extrude the working part of the extrusion die The inner cone angle is 90°~140°, and the extrusion rate is 10~20mm / s. The invention can realize fine-grained and weak texture structure, and improve the isotropy, high yield ratio and high ductility of the liner.

The invention relates to a thermo-mechanical treatment process for improving the performance of a high-strength heat-resistant wrought magnesium alloy barrel-shaped part, and belongs to the field of nonferrous materials and processes. The technology of aging heat treatment after spinning deformation is adopted, continuous and pointwise plastic deformation is generated through spinning point-contact deformation at high temperature, even deformation of the barrel-shaped part is realized, the deformation degree is improved, the structure performance is uniform, and the isotropy of the performanceof the wrought magnesium alloy barrel-shaped part is realized. The process is divided into two phases. In the first phase, the deformation degree of the barrel-shaped part is improved through high-temperature spinning deformation, the structure performance is uniform, the grain refinement strengthening effect of WE71M wrought magnesium alloy is played, and the mechanical performance of the WE71Mbarrel-shaped part is improved. In the second phase, aging heat treatment is conducted on the barrel-shaped part after being subjected to spinning deformation, separation of a discontinuously separated dispersion strengthening phase at the grain boundary is facilitated, and the performance of the material is improved. The performance of the barrel-shaped part is further improved after high-temperature deformation heat treatment, and the structure is more uniform.

An embodiment of the invention provides a method for preparing a composite material. The method comprises the following steps of: forming a semispherical groove of a preset array on a first substrate; filling a preset spherical dielectric material in the semispherical groove of the first substrate, the diameter of the spherical dielectric material being the same as that of the semispherical groove; forming a semispherical groove the same as that of the first substrate on a second substrate; and splicing the first and second substrates to embed the spherical dielectric material in a spherical cavity formed by splicing the first and second substrates, thereby obtaining the composite material. The composite material is obtained by splicing the spherical dielectric material in the substrates to achieve isotropy and a simple process flow.

The invention discloses a device and a method for analyzing a transmission type charge-coupled device (CCD) imaged image. The device comprises a sample placing module, an image acquisition module and a control module, wherein the sample placing module comprises a porous liquid sample transparent vessel and a bracket; the image acquisition module comprises a light emitting diode (LED) uniform transmission light source module, an optical imaging module and a photoelectric conversion module; and the control module comprises a master control module, a computer, a bracket driver module and a data transmission module. The method comprises the following steps that: the image acquisition module and the control module in the device are reset; the porous liquid sample transparent vessel filled withexperiment samples is fixedly arranged in the bracket; the master control module controls the bracket to pass through a position between the LED uniform transmission light source module and the optical imaging module at a constant speed through the bracket driver module; and the image is acquired by the image acquisition modules, transmitted to the computer by the data transmission module and analyzed. The device can fast image a plurality of liquid samples at one time, can be smoothly operated and has high recognition accuracy rate.

The present invention provides one kind of adaptive filled expanding sieve tube for preventing sand in oil and gas well, and belongs to the field of petroleum drilling and extracting tool technology. The adaptive filled expanding sieve tube consists of supporting slotted tube, special filling coupler, radial expanding cover, radial expanding composite filter element, supporting rack, expanding block, expanding screw, plug and other parts. During well operation, the adaptive filled expanding sieve tube is set in the oil reservoir and filled with high pressure carrying solid particles, so that the composite filter element and the radial expanding cover can expand radially to contact with the inner wall of the production casing or the uncased hole to block sand and control the size of the passed sand. Compared with available technology, the present invention has the advantages of lowered expanding force, low operation cost and other advantages.