31results about How to "Reduce internal cracks" patented technology

A periodic tube rolling machine with slant rolling drill rig is used to generate big caliber thick wall steel blocks, to satisfy the inside and surface quality requirements. Inner cavity working section of the mold is wave shape multilateral cross section shape wave ingot mold, with sulfur content controlled under 0.025% of the steel liquid, casting temperature within 40 to 80DEG C, linear speed 80 to 230mm/min, cracking ratio lower than 5%, pass rate 98.81%, with low consumption of metal, low cost, especially suitable for rolling into seamless steel tubes with multi types and specification and phi>/=426mm.

The invention provides a green preparation method and a filter for a lightweight high-strength cordierite porous ceramic. The preparation method comprises the following steps: step S10, mixing magnesium oxide, aluminum oxide and silicon dioxide according to a cordierite stoichiometric ratio to obtain mixed powder, adding the mixed powder into deionized water with a certain volume, ball milling andmixing to prepare slurry; step S20, foaming the slurry to obtain foam slurry; step S30, injecting the foam slurry into a mold for freeze drying; step S40, sintering the dried green body to obtain thelightweight high-strength cordierite porous ceramic. According to the invention, the green preparation method is small in additive dosage used and environment-friendly, the size change from injectionmolding to sintering is less than 2% (the bus shrinkage range is-1.87% to 0.45%), and the method accords with the technical characteristic of green preparation.

The invention provides a method for producing high-quality 75Cr1 hot-rolled sheet steel based on the continuous thin slab casting and rolling process, which mainly adopts the following process flow: smelting, refining, continuous thin slab casting, soaking, hot continuous rolling, cooling and coiling. The superheat T of molten steel is larger than 30 DEG C and less than or equal to 45 DEG C, the charging temperature T of the cast slab is larger than or equal to 900 DEG C and less than or equal to 1050 DEG C, the finish rolling temperature T is larger than or equal to 850 DEG C and less than or equal to 950 DEG C, the coiling temperature T is larger than or equal to 550 DEG C and less than or equal to 630 DEG C, and the drawing speed S of continuous casting is larger than or equal to 3.5m/min and less than or equal to 5.5m/min; mold flux casting is adopted; and the chemical composition of molten steel is as follows: 0.70 percent to 0.80 percent by weight of C, 0.20 percent to 0.45 percent by weight of Si, 0.60 percent to 0.90 percent by weight of Mn, 0.025 percent by weight or less of P, 0.025 percent by weight or less of S, 0.30 percent to 0.60 percent by weight of Cr and 0.02 percent to 0.08 percent by weight of V. When the method is adopted to produce the 75Cr1 hot-rolled sheet steel, the segregation, porosity and cracks of the cast slab are reduced, and the 75Cr1 hot-rolled sheet steel is characterized by uniform microstructure and properties and high fatigue resistance.

The invention provides a method for reducing cracks of nickel-based superalloy formed by SLM (selective laser melting) and improving mechanical property. The method comprises the following steps: pouring yttrium nitrate powder into absolute ethyl alcohol, and carrying out ultrasonic vibration stirring until the yttrium nitrate powder is completely dissolved; pouring GH3536 nickel-based high-temperature powder into a yttrium nitrate absolute ethyl alcohol solution, and carrying out ultrasonic vibration stirring, enabling metal powder and the solution to be fully contacted and wetted; drying the obtained solid-liquid mixture, then putting the solid-liquid mixture into a tubular furnace for calcining, and then cooling along with the furnace; grinding and screening the obtained calcined powder to obtain GH3536 powder uniformly coated with yttrium oxide; and preparing a GH3536 nickel-based high-temperature alloy block sample from the yttrium oxide uniformly coated GH3536 nickel-based high-temperature powder through a selective laser melting method. According to the method, the number of cracks in the SLM printed GH3536 nickel-based high-temperature alloy is effectively reduced, the microstructure state is improved, and the mechanical property of the GH3536 nickel-based high-temperature alloy is greatly improved.

The invention discloses an improved production technology for fine dried noodles. The improved production technology comprises the following steps: A, kneading a dough, namely selecting wheat flour with the gluten content of 32-34% and the protein content of 18-19%, and kneading the dough, wherein a mixing ratio of the wheat flour to water is 2:1; B, curing, namely carrying out standing on the dough in an environment at the temperature of 40 DEG C and the humidity of 70%, and curing for 3 hours; C, pressing into sheets, namely putting the cured dough into a noodle press, and pressing into the sheets with the thickness of 1mm; D, preliminary drying, namely putting the sheets into a drying room, and drying for 10 minutes while a drying temperature is controlled to be 45-55 DEG C; E, slitting, namely slitting the preliminarily dried sheets; F, drying, namely drying the noodles; G, cutting, namely cutting the dried noodles according to set length; and H, packaging, namely weighing the cut fine dried noodles, and packaging. The improved production technology for the fine dried noodles has the advantages that defects of the prior art can be solved, and fracture rate of the fine dried noodles is reduced.

The invention relates to a matte dry granular material and a preparation method thereof. The matte dry granular material is mainly prepared from the following raw materials in parts by weight: 30-45 parts of potassium feldspar, 5-15 parts of albite, 6-10 parts of kaolin, 10-20 parts of barium carbonate, 3-8 parts of wollastonite, 3-10 parts of zinc oxide, 4-10 parts of strontium carbonate, 7-13 parts of calcite, 1-4 parts of quartz and 1-5 parts of aluminum oxide. The matte dry granular material shows stable matte gloss at different specifications of firing temperatures, and has excellent physical properties such as wear resistance and pollutant resistance.

The invention discloses a post treatment process of man-made stone raw materials. After pressing and before cutting, the man-made stone raw materials are subjected to soaking and curing treatment by liquid media with the temperature higher than the normal temperature; and then, normal-temperature maintenance is performed. The post treatment process has the advantages that the pressed man-made stone raw materials are subjected to maintenance post treatment, so that the traditional normal-temperature maintenance node is changed; the mode of firstly performing soaking, heating and curing treatment by liquid media with the temperature higher than the normal temperature and then performing normal-temperature maintenance is used; by using the post treatment process of soaking, heating and curing, unsaturated polyester resin reaction can be sufficient; and the stable product performance is achieved on the original basis, so that the quality problems of internal cracking, easy product deformation, warping and the like of the man-made stone raw materials are reduced.

The invention provides an alumina hollow ball brick and a preparation method thereof. The alumina hollow ball brick is prepared from the following raw materials by weight: 30-50 parts of alumina hollow balls with particle sizes of no less than 4 mm, 8-20 parts of fine white corundum powder with a particle size of no less than 150 meshes, 5-10 parts of silicon carbide with particle size of no lessthan 200 meshes, 8-16 parts of alumina micropowder with a particle size of no less than 500 meshes, 2-4 parts of kyanite micropowder with a particle size of no less than 500 meshes, 2-4 parts of sillimanite micropowder with a particle size of no less than 500 meshes, 4-7 parts of clay micropowder with a particle size of no less than 200 meshes and 8-12 parts of a binder. The alumina hollow ball brick of the invention has the characteristics of high temperature resistance, high strength, good thermal shock resistance, fuel economy and the like, and is particularly applicable to high-temperatureroller bar sintering kilns and kilns with similar working conditions; and the preparation method is simple in process and easy to implement, and has wide application and promotion value.

The invention belongs to the technical field of ceramic manufacturing equipment, and particularly relates to a stable ceramic press green body receiving platform. The stable ceramic press green body receiving platform comprises a green body receiving roller platform and a press which are connected. The ends, close to the press, of the left side and the right side of the green body receiving rollerplatform are provided with automatic extensible and retractable positioners. Each automatic extensible and retractable positioner is composed of a fixed device, a movable extensible and retractable device and a control device, wherein the fixed device comprises a fixed part and an abutting part, the fixed part is arranged on a middle frame of a press mold, the abutting part is arranged on the green body receiving roller platform, the abutting part can be driven by the movable extensible and retractable device to be completely embedded into the fixed part, and therefore stable positioning of the green body receiving roller platform and the press is guaranteed; and the control device is used for judging the positioning state of the green body receiving roller platform and the press and controlling work of the movable extensible and retractable device according to the positioning state. According to the stable ceramic press green body receiving platform, a vibration value of the roller platform is reduced, green body receiving is stable, and probability of internal hidden fractures and cracks in green bodies is greatly reduced.

The invention relates to a preparation method of an epoxy resin profile. The preparation method comprises the following steps that raw materials are uniformly mixed to obtain a mixture, and the mixture is preheated; the mixture is distributed, so that the mixture is uniformly distributed on a transmission device; the mixture on the transmission device is subjected to gradient heating, and then themixture is segmented to obtain a semi-finished product; the semi-finished product is subjected to heat preservation; the semi-finished product after heat preservation is pressed into a mold to be molded to obtain the epoxy resin profile, and the semi-finished product is subjected to gradient cooling in the forming process; and after the epoxy resin profile and the mold are cooled, demolding and blanking and forming are carried out, and then a film pasting is carried out to obtain an epoxy resin profile finished product. The epoxy resin mixture is subjected to gradient heating during gelationand curing to form an epoxy resin cured product, and the epoxy resin cured product adopts gradient cooling in the forming process of the epoxy resin cured product, so that internal stress generated inthe preparation process of the epoxy resin profile is reduced, cracks generated in the preparation process are reduced, and the problem that the finished product is prone to cracking after a period of time is used is reduced.

The present invention provides a method for producing a Cu—Ni—Sn alloy, which achieves both productivity and product quality by reducing internal cracks and dispersing Sn uniformly while shortening the time for cooling an ingot. The method for producing a Cu—Ni—Sn alloy is a method for producing a Cu—Ni—Sn alloy by a continuous casting method or a semi-continuous casting method, the method including: pouring a molten Cu—Ni—Sn alloy from one end of a mold, both ends of which are open, and continuously drawing out the alloy as an ingot from the other end of the mold while solidifying a part of the alloy, the part being near the mold; performing primary cooling by spraying a liquid mist on the drawn-out ingot; and performing secondary cooling by immersing the ingot having been subjected to the primary cooling in a liquid, thereby making a cast product of the Cu—Ni—Sn alloy.

The present invention discloses an artificial stone rough block curing process, which artificial stone rough block is subjected to spraying curing treatment by using a liquid medium with a temperature of higher than a normal temperature after pressing and before cutting, and then normal temperature curing is performed. According to the present invention, the pressed artificial stone rough block is cured, the traditional normal temperature curing way is changed, the way sequentially comprising heating curing through the spraying of the liquid medium with the temperature of higher than the normal temperature and the normal temperature curing is used, and through the spraying heating curing process, the reaction of the unsaturated polyester resin can be complete, the relatively stable product performance can be achieved on the original basis, and the quality problems of internal cracking, easy product deformation generation, easy product warping generation and the like of the artificial stone rough block can be reduced.

A glass/quartz composite structure comprises quartz grit, quartz powder and glass grit wherein the glass grit is in an amount greater than 50% by weight of the composite structure, and a binding resin. The glass/quartz composite structure may be formed into a 1.2-1.5 cm thick slab for countertops using standard cabinet perimeter support. The slab may be made by mixing the quartz grit, the quartz powder, the glass grit, and the binding resin, pouring the mixture in a mold, and compacting the mixture in the mold. Specific natural mineral components may be added to the glass/quartz/resin composite structure to provide aesthetics of specific natural stones.

The invention relates to the technical field of stainless steel material processing, in particular to a processing method of nitrogen-containing austenitic stainless steel. According to the technical scheme adopted by the invention, the processing method comprises the following steps of: (1) heating a steel billet of the nitrogen-containing austenitic stainless steel to 1100 to 1250 DEG C by a walking beam furnace, preserving heat for 1 to 1.5 hours, and then performing heat-insulating treatment on the steel billet of the nitrogen-containing austenitic stainless steel subjected to heat preservation; and (2) performing rolling by a hole-free flat roll roughing mill unit, wherein in the rolling process, the elongation coefficient of each pass is controlled to be 1.25 to 1.35, the broadening coefficient is controlled to be 0.10 to 0.42, and the operating speed of the steel billet in the rolling process is 0.60 m/s to 1.12 m/s. The processing method has the advantages that by the processing method, the properties such as strength, toughness and corrosion resistance of the produced economical medium-nitrogen austenitic stainless steel can be guaranteed to be more reliable; the use requirements in the wider use environments can be met; and the lower overall cost in the production process is guaranteed.