37results about How to "Extended stability" patented technology

The invention provides a method for making tough metallic glass generate macroscopic stretching plasticity. The method comprises the following steps: 1, preparing tough metallic glass to be processed, making the tough metallic glass into a rodlike workpiece, and determining the length and diameter data of the workpiece; 2, according to the influential scope of the effective stress area, designing a corresponding thread structure to be processed on the surface of the workpiece; 3, fabricating the corresponding thread area on the surface of the workpiece according to the design result, so that the threaded workpiece high in stretching plasticity is obtained. According to the method, the thread structure is utilized, the tough metallic glass can be excited to generate multiple shear bands in the uniaxial stretching state, in addition, through the geometric hindrance and limitation effect of the surface micro-thread structure, expansion of the main shear band can be stabilized, and macroscopic stretching plastic deformation is caused.

The invention discloses a method for measuring the threshold value of stress intensity factor of type II cracks in metal materials. The left end of the sample is fixed by a sample fixing mechanism, the right end is provided with a horizontal gap extending from the right end to the center, and the inner end of the gap is provided with a tip facing the right end The triangular crack initiation and expansion part of the surface, and the vertical edge at the tip is provided with a V-shaped notch, and a support rod is inserted into the gap; between the upper clamping part and the upper cantilever of the clamping mechanism package and the lower clamping part and There are stress conducting rods between the lower cantilevers. The fatigue testing machine applies a reciprocating load through the upper cylinder on the upper part of the upper clamping part. After the test, cut the sample perpendicular to the end face, observe the type II crack, and calculate the type II The magnitude of the stress intensity factor corresponding to the critical length of the crack is the threshold value of the stress intensity factor for the type II crack of the metal material. The invention is beneficial to ensure the initiation of cracks on the neutral plane, to ensure that the shear stress decreases with the increase of the crack length, and to ensure the stable expansion of the cracks along the neutral plane of the sample.

The invention relates to the field of mechanical property evaluation and characterization of materials, and in particular relates to a method for evaluating the tearing toughness of ductile metal materials. The method is characterized in that through carrying out a tearing test on ductile metal materials by using three-leg trouser-shaped samples, a characteristic that applied loadings in the process of tearing are unchanged is obtained, thereby providing a powerful test basis for the proposition of a tearing toughness concept, thereby obtaining a defined tearing toughness which is shown in a formula as follows: Gamma = FS / 2 t, and used for evaluating the toughness or crack propagation resistance of ductile materials. The tearing test method and the tearing toughness concept provide an effective thought for knowing an inversion relation between the strength and plasticity (toughness) of a material, therefore, a new reference criterion is provided for selecting materials (the strength and plasticity are fitted better) for actual engineering. As for ductile sheet metals, a crack propagation process and a fracture process can be described more accurately by using the tearing toughness, which has a vital significance to the evaluation and characterization of engineering applications and mechanical properties of materials.

A low-stress and high-efficiency precise blanking method for medium-high frequency inductive heating of a rod tube material is characterized in that the rod tube material is put on a feeding mechanism and then is fed in an inductive heating device; the inductive heating device can control heating time and a surface layer heating depth in a V-shaped groove of the rod tube material through adjusting parameters, such as heating frequency, current magnitude and the like, so as to finish quick heating to the V-shaped groove of the rod tube material; and then, the heated rod tube material is fed in a blanking mechanism, and is fixed by a rod tube material fixing sleeve; circular periphery loads are loaded in the radial direction of the rod tube material; and blanking is implemented by using a stress concentration effect, a heat stress effect and a fatigue break mechanism of the rod tube material. The method has the advantages of high efficiency, low energy consumption, material conservation and good blanking quality.

In card clothing for a textile machine comprising a plurality of adjacent spaced-apart needles or serrated punched cut-outs disposed in rows, wherein the needles or serrated punched cut-outs are stamped and accordingly have a non-rectangular cross-sectional geometry, wherein a free passage zone for the fibers being combed is formed between the spaced-apart needles or serrated punched cut-outs, it is provided that the free passage zone (A) steadily widens viewed in the direction of travel of the sliver.

The invention relates to a bidirectional hydraulic hole-expanding type pipeline break simulation experiment device. The experiment device comprises a pipeline support system, a pipeline expanding and supporting system, an oil inlet pipe and a DIC (density indicating controller) testing system, wherein an axial penetrating precrack is formed in the side wall of an experiment pipe section, and is symmetric to the axial center surface of the experiment pipeline section; the pipeline support system is used for supporting both ends of the experiment pipeline section; the pipeline expanding and supporting system is positioned in the experiment pipeline section, and the oil from the oil inlet pipe is used for providing hydraulic power for the pipeline expanding and supporting system; the pipeline expanding and supporting system is used for expanding and supporting the experiment pipeline section, and the precrack is expanded in two directions; the DIC testing system is used for observing the breaking process of the experiment pipeline section in real time. The experiment device has the advantages that the experiment sampling adopts the full-size pipeline sampling, a sample is directly cut from a pipeline, the size error, constraint error and the like are reduced, and the data reliability is guaranteed; by adopting a hydraulic driving device in an experiment, the working risk is decreased, and the cost is reduced; the DIC testing device is used for observing the expanding condition of the crack in real time, and the required data is conveniently obtained.

The invention relates to a one-way driven semi-crack pipe fracture simulation experiment device. The device comprises a pipe support system, a pipe expansion system and a DIC test system. The pipe support system supports both ends of an experimental pipe section. The inner end face of the pipe expansion system coincides with the axial midface of the experimental pipe section. The pipe expansion system extends the experimental pipe section through pull rod or screw driving so that the experimental pipe section is broken. The DIC test system realizes real-time observation of the breaking process of the experimental pipe section. Compared with the prior art, the device utilizes a full-size pipe sample as an experimental specimen directly captured from the pipe, reduces and limits the size error, and ensures the reliability of the data. The experiment uses the hydraulic cylinder or the electric motor driving device, reduces a work risk and reduces a cost. In the experimental process, by controlling the movement speed of the pull rod and screw, a fan-shaped block expanding rate can be controlled, a crack expansion rate can be controlled and the accuracy of the data is guaranteed.

The invention discloses a DC converter digital parallel current equalizing method and system. The method comprises that: a host periodically acquires present load current and calculates a present current equalizing set value and issues the value in combination with last time current equalizing set values issued to multiple parallel-connected slaves last time; and whether load current adjustment of each slave is executed is judged by each slave according to the acquired present current equalizing set value and the stored current equalizing set value last time, and when a difference value between the present current equalizing set value and the current equalizing set value last time is greater than or equal to the preset minimum current equalizing error threshold value, the load current adjustment of the slaves is executed according to the present current equalizing set value, wherein the minimum current equalizing error threshold value can be set as zero. With application of the method, the DC converter digital parallel current equalizing system can still operate stably even interference appears or loads are switched so that great robustness is realized.

The invention relates to an opposite-cutting type blanking machine for driving linear motion of double screw rods by an AC (Alternating Current) servo motor, which comprises a driving mechanism, a blanking radially-loading blanking mechanism and a feeding radially-loading blanking mechanism. The linear motion mode of a ball screw can be utilized to carry out the design of high speed blanking, the linear motion speed of the molds can be improved by the design of the inverse motion of two sets of movable molds, and the blanking process is simple and practical by the design of the instant, rapid motion and the rapid and accurate returning of the molds; the blanking molds can be replaced according to the different process requirements; and rod pipe materials can be preciously discharged by aiming at different materials and different diameters. The opposite-cutting type blanking machine has the advantages of compact structure, high efficiency, low energy consumption and the like and is practical and convenient.

The invention relates to a bi-directional driving type pipeline fracture simulation experiment device, which comprises a pipeline support system, a pipeline expansion support system and a DIC test system, wherein an axial penetrating precast crack is formed in the side wall of an experiment pipe section; the precast crack is symmetrical about the axial middle surface of the experiment pipe section; the pipeline support system supports the two ends of the experiment pipe section; the pipeline expansion support system performs expansion support on the side wall of the experiment pipe section through pull rod or lead screw traction, so that the experiment pipe section fracture is caused; the DIC test system observes the fracture process of the experiment pipe section in real time. The bi-directional driving type pipeline fracture simulation experiment device has the advantages that an experiment test specimen is a full-scale pipeline test specimen, and is directly cut from the pipeline; the error is reduced; the data reliability is ensured; a hydraulic cylinder or an electric motor driving device is used for experiment; the work risk is reduced; the cost is reduced; the opening speed of a fan-shaped block can be controlled by controlling the moving speed of a pull rod and a lead screw; meanwhile, the expansion speed of the crack is controlled; the accuracy of the obtained data is guaranteed.