86results about How to "Eliminate microcracks" patented technology

The making process of circular polarization maintaining fiber includes deposition process to make core rod and stress rod with preserved coating, machining mechanically the matched sides of the core rod and the stress rod to reach the matching interval requirement, machining mechanically the inner hole of quartz casing for fitting the combined cross section of the core rod and the stress rod, setting the machined core rod and stress rod into the quartz casing for matching tightly to constitute prefabricated rod for circular polarization maintaining fiber, drawing, cleaning, and re-drawing to form fiber. The making process has high precision, high product quality and powerful adaptability, and is suitable for mass producing circular polarization maintaining fiber product.

The invention discloses a technological method for composite asynchronous polishing of ceramics using picosecond-nanosecond laser. The technological method comprises the steps of firstly, irradiatingthe ceramic surface to be machined through picosecond laser along a certain scanning trace, and removing micro protrusions of the ceramic surface, so that the preliminary flattening is achieved; meanwhile, generating a large number of micro-nano particles by using a removal mechanism for the electronic state of ceramic materials through picosecond laser, wherein the micro-nano particles exist at adjacent space areas of the irradiated ceramic surface; starting a low power nanosecond laser according to the preset time for tracing the scanning path of the picosecond laser, and irradiating and fusing the micro-nano particles uniformly distributed on the ceramic surface; and finally forming a compact and smooth fine-grain melted layer so that the polishing effect is achieved. According to the technological method, original pore cracks of the ceramic materials are repaired, and the shortcomings that a heat affected zone generated by traditional laser polishing is large and the material surface is liable to generate micro-cracks and pores are overcome; and low removal amount, high efficiency and accuracy and submicron-level fine polishing of the ceramic materials is achieved.

The invention relates to a method for preparing a high-entropy alloy through laser additive manufacturing. The method comprises the following steps that A, grinding, washing and drying of substrates are carried out, and the substrates are preheated; B, prepared high-entropy alloy powder is subjected to ball milling treatment and is stirred evenly to be subjected to deposition; C, according to theperformance requirements of bulk high-entropy alloy components, laser processing parameters for machining each deposition layer is pre-designed; D, according to the preset laser processing parametersof each layer, the surfaces of the substrates are subjected to layer-by-layer variable parameter laser additive manufacturing; and E, after processing is carried out, prepared bulk alloy components are slowly cooled to room temperature, a wire cutting method is used for separating the additive manufacturing components from the substrate, and then hot isostatic pressing is carried out. By means ofthe method, while the molded piece performance is met, the production cycle is shortened, cost is reduced, and large-scale parts in complicated shapes can be prepared.

The invention relates to a rolling method of small-roughness high-gross thin tungsten sheet, pertaining to the rolling method of thin tungsten sheet. The method of the invention is characterized in that: a. surface processing of tungsten board material: the surface of tungsten board is regrinded, electrolyte of 1% NaOH + 4% K2CO3 + 4% KClO3 + H2O is adopted to polish the tungsten board for 10 to 30min; b. a regrinding and rolling roller with roughness smaller than 0.1Mum is used; c. the preheating temperature of the roller is 100 to 150 DEG C; d. the preheating temperature of the tungsten board material is 100 to 200 DEG C; e. surface processed and preheated tungsten board is directly rolled on a preheated four-roll or six-roll rolling machine, with the total processing rate controlled between 20 to 30 percent, rolling force 40T to 100T. The method of the invention can prepare thin tungsten sheets with uniform and bright surface and the surface roughness is smaller than 0.15Mum.

The invention discloses a hard-surface gear processing device, in particular to a hard-surface gear hobbing processing device which comprises a cutter and a hard-surface gear hobbing machine and is characterized in that the cutter adopts a hard-surface gear hobbing plate, a main motion transmission chain is shortened to a limit by the hard-surface gear hobbing machine, a working main shaft of the hard-surface gear hobbing machine is in a horizontal structure, and a dividing mechanism of the hard-surface gear hobbing machine comprises a plane worm wheel and a plane enveloped worm gear. In the hard-surface gear processing device, the hard-surface gear processing cutter has reliable operation, simple use and low cost, a hard-surface gear hobbing processing lathe has high rigidity and efficiency, eliminates the deformation of the quenched gear, reduces noise, provides an economic technology for processing the quenched gear, eliminates fine crackles on the gear surface of the quenched gear, and improves the anti-fatigue performance of the gear so as to prolong the service life of the gear.

The invention discloses a high-air-tightness low-free-oxygen-content nano disperse copper alloy and a short-process preparation technology, and wherein the alloy components comprise Al2O3, Ca and La.The preparation technology is made by the following steps that preparing Cu-Al2O3 alloy powder by adopting an internal oxidation method, and then mixing the Cu-Al2O3 alloy powder with Cu-Ca-La alloy powder, wrap covering the mixed powder under the protection of argon, carrying out hot extrusion at 900-920 DEG C and then rotary forging, after rotary forging, the wrap covering is vacuumized to be less than or equal to 10<-3>Pa, the wrap covering is sealed and is placed in a nitrogen atmosphere with the temperature of 450-550 DEG Cand the pressure intensity of 40-60 Mpa for 3-5 hours. According to the preparation technology disclosed by the invention, the secondary solid reduction of Ca and La is utilized, so that residual free oxygen is effectively removed and the dispersion strengthening effect is achieved, and finally the high density is obtained through vacuum medium-temperature creep deformation. The disperse copper prepared by the invention has the advantages that low free oxygen content (<= 15ppm), high dimensional stability and good air tightness after hydrogen annealing, good in gas tightness, the gas leakage rate is less than or equal to 1.0*10<-10> Pa.m<3> / s, the preparation technology is suitable for industrial production and can be used as a variety of sealing device materials such as an electric vacuum shell sealing device and a novel energy automobile high-voltagedirect-current relay.

The invention described herein discloses a chemical mechanical machining and surface finishing process. A conversion coating is formed on the surface of a workpiece and is removed via relative motion with a tool, thereby exposing the workpiece to further reaction with the active chemistry. Low mechanical forces are used such that the plastic deformation, shear strength, tensile strength and / or thermal degradation temperature of the workpiece are not exceeded. Since the chemical mechanical machining and surface finishing process requires little force and / or speed of contact to remove the conversion coating, the equipment's mass, complexity and cost can be significantly reduced, while simultaneously increasing machining precision and accuracy. The present invention lends itself to a very controlled rate of metal removal, and can simply surface finish the workpiece, or if desired, can surface finish the workpiece simultaneously with the shaping and / or sizing process.

The invention discloses a TiAl-based alloy stator blade isothermal forming manufacturing method and a device thereof, and belongs to the field of isothermal forming manufacturing methods. The method comprises the steps of machining blank manufacturing, isothermal pre-forging, isothermal final forging and heat treatment. The invention further provides a TiAl-based alloy stator blade isothermal forming device. Compared with a commonly-adopted machining mode that a square blank is extruded and then machined into a part, and due to the fact that the extruded square blank is not deformed, the structure and the performance of a prepared stator blade cannot meet the design requirements, according to the method provided by the invention, blade forging forming is achieved through machining blank manufacturing and isothermal forming, and then the blank is machined into a part. Due to the fact that a TiAl-based alloy is large in deformation resistance and poor in shaping, a common forming methodcannot be achieved, so that the blank manufacturing process is a major problem needing to be solved. According to the method, turning is adopted for blank manufacturing, the blank shape is close to the shape of a final forging, isothermal forging forming is adopted, and uniform deformation of all parts of a blade is achieved, so that the structure and the performance of the blade forging are greatly improved.

The invention discloses a heating sheet and a preparation method and application thereof. The heating sheet comprises a base body and a surface enamel layer. The base body comprises a lower substratelayer, a lower insulation layer, electrodes, an upper insulation layer, an upper substrate layer and a contact electrode, and the lower insulation layer is arranged on the lower substrate layer; the electrodes are arranged on the lower insulation layer and comprise the lead electrode and the heating electrode which are connected; the upper insulation layer is arranged on the electrodes, and a first open hole is formed in the upper insulation layer; the upper substrate layer is arranged on the upper insulation layer, and a second open hole is formed in the upper substrate layer and connected with the first open hole; the contact electrode is arranged on the upper substrate layer and electrically connected with the lead electrode through the second open hole and the first open hole in sequence; the surface enamel layer is arranged to surround the outer surface of the base body and does not cover the contact electrode. The heating sheet is low in preparation difficulty, long in service life and high in efficiency and has a good heating effect.