11 results about "Cupronickel" patented technology

The invention discloses a wall thickness difference cupronickel and beryllium copper foil transition welding method for a CT bulb tube. The method comprises the following steps that S1, materials are pretreated; s2, assembling is conducted, specifically, a copper foil sheet is placed at a ray window in the side wall of the cupronickel tube shell, the inner side and the outer side of the copper foil sheet are both coated with welding flux, a beryllium sheet is placed on the outer side of the copper foil sheet, the beryllium sheet and the copper foil sheet are the same in size and radian, a welding tool is placed on the outer side of the beryllium sheet to fasten the copper foil sheet and the beryllium sheet, and assembling of a to-be-welded assembly is completed; and S3, welding. Through high thermal conductivity and low yield strength of the copper foil, uniform distribution of heat and stress buffering are realized, on one hand, excessive heat gathered by thin-wall cupronickel can be quickly conducted to thick-wall cupronickel, and overall heat distribution is balanced through the heat storage capacity of the thick wall; and on the other hand, the uniform thermal conductivity of the copper foil can reduce the local temperature difference of a welding seam area, micro cracks or air holes generated due to uneven thermal expansion and cold contraction are avoided, and the welding air tightness is improved fundamentally.

This invention discloses a method for removing internal inclusions in complex copper alloys produced by centrifugal casting, relating to the field of aluminum cupronickel alloy casting technology. The specific steps are as follows: S1, alloy melting: raw materials are added to a melting furnace according to the copper alloy composition ratio and heated to melt, with the melting temperature controlled at 1290–1380℃; slag removal and refining are performed during the melting process to remove oxide inclusions and gases from the melt; after the melt composition is homogeneous, it is kept at a constant temperature and allowed to stand, and the alloy temperature is adjusted to 1150–1220℃ before pouring; S2, mold preheating: the metal mold is preheated to 120–200℃. This invention introduces pouring angle control on the basis of traditional centrifugal casting process parameters, constructing a multi-parameter collaborative control mechanism of "rotation speed—temperature—time—angle," which can effectively suppress liquid surface fluctuations and turbulence during the filling process, reducing the probability of gas entrapment and inclusion defects; meeting the engineering application requirements of large-size, high-performance aluminum cupronickel alloy rings.

The application discloses a cupronickel rust removal and passivation solution, a cleaning method and a shell-and-tube heat exchanger. The cupronickel rust removal and passivation solution is composed of 8-15% of inorganic acid, 0.1-0.5% of corrosion inhibitor and passivation agent (consisting of copper alloy corrosion inhibitor and black metal corrosion inhibitor) and the rest of B-grade water. After the cupronickel rust removal and passivation solution is circulated for 90-120 minutes, a uniform passivation film can be formed on the surface of BFe1011 or BFe3011 cupronickel, and the corrosion rate of the base material and the weld is less than 0.01 mm / a. The application also provides a corresponding pickling and passivation method, which comprises the steps of circulation treatment, displacement rinsing and drying and inspection. The problems of high corrosion rate, poor passivation film quality and lack of heterogeneous metal protection in the traditional pickling method are solved, and efficient and low-corrosion maintenance is realized.

The application discloses a production method of high-gloss C7451 cupronickel strip, and comprises the following steps: melting and casting, face milling, rough rolling, thick shearing, first-time shield annealing, degreasing and cleaning, pre-finishing rolling, loose coiling, second-time shield annealing, degreasing and cleaning, finishing rolling, air cushion furnace annealing, loose coiling, third-time shield annealing, degreasing and cleaning, bending and straightening, and finished product slitting; in the finishing rolling step, 2 passes of rolling are carried out, the second pass reduction is controlled to be 5-10%, the total reduction of the finishing rolling is controlled to be more than 30%, and the roughness of the finishing rolling roller is controlled to be 0.05-0.15 microns; the method can stably produce the high-gloss C7451 cupronickel strip with a tensile strength of 540-590 MPa, an elongation of 10-15%, a hardness of 160-175 HV, and a glossiness of more than 350 GU.

The invention provides a method for improving the thermal cracking resistance of a cupronickel alloy without adding an alterant, which comprises the following steps: step (1), heating and melting a cupronickel alloy raw material, fishing out the cupronickel alloy raw material, and covering charcoal and surface scum; (2) the smelting temperature is increased to 1350 + / -50 DEG C, and melt is fully stirred during heating; (3) keeping the temperature at 1350 + / -50 DEG C, standing for 8-20 minutes, and fishing out the dross after the dross in the melt fully floats upwards; step (4), covering with calcined charcoal with the thickness of 10-20 cm; (5) the temperature of the melt is reduced to 1200-1310 DEG C, casting is conducted, and the casting speed is 3.5-5.1 m / h; and (6) the round ingot obtained through casting is heated to 900-1075 DEG C, extrusion is conducted, and the cupronickel alloy pipe blank is obtained. According to the method, under the condition that no alterant is added, the cupronickel alloy which is uniform in microstructure and small in grain size is successfully prepared by controlling the smelting temperature, the standing time and the casting speed, and the high-temperature heat crack resistance and the ductility of the cupronickel alloy are remarkably improved; and meanwhile, the furnace life is effectively prevented from being influenced by alterant slagging, and the equipment maintenance cost is reduced.

The invention discloses a mechanical-chemical composite polishing method for reducing the roughness of the inner wall of a cupronickel pipe. The mechanical-chemical composite polishing method comprises the following steps that (1) pollutants on the surface of the cupronickel pipe are removed through alkali washing; (2) an etching and polishing solution is introduced into the cupronickel tube subjected to alkali washing in the step (1) for polishing treatment, wherein the etching and polishing solution is turbid liquid containing nano-diamond particles, ferric trichloride and hydrochloric acid; and (3) cleaning and drying the cupronickel tube polished in the step (2). The nano diamond particles are added into the etching polishing solution, mechanical-chemical composite polishing of the inner wall of the cupronickel pipe is achieved, the smooth, clean and defect-free inner wall of the cupronickel pipe is obtained, and the etching polishing solution is suitable for simple cupronickel alloy pipes with various components and sizes, especially cupronickel pipes with large diameters and lengths. By the adoption of the method, the surface machining defects can be eliminated, the cupronickel pipe with the inner wall surface roughness Rsa being 0.1-0.23 m is obtained, the cupronickel pipe is used for treating the cupronickel pipe for maritime work equipment, the pitting corrosion resistance of the cupronickel pipe can be remarkably improved, and the requirement for the long service life of the cupronickel pipe can be met.

The invention discloses a free-cutting complex cupronickel alloy and a preparation method and application thereof. The free-cutting complex cupronickel alloy is prepared from 42 wt%-45.5 wt% of Cu, 10 wt%-13 wt% of Ni, 4 wt%-6.5 wt% of Mn, 1.5 wt%-2.5 wt% of Pb, 0.001 wt%-0.2 wt% of Al, 0.001 wt%-0.3 wt% of Sn and the balance Zn and inevitable impurities. Wherein (WNi + WMn) * 100 is larger than or equal to 16 and smaller than or equal to 18, and WNi and WMn represent the mass percentage contents of Ni and Mn in the free-cutting complex cupronickel alloy; the free-cutting complex cupronickel alloy comprises an alpha phase, a beta phase and a Pb phase, the average size of the Pb phase is smaller than or equal to 3 micrometers, and the distribution density of the Pb phase is larger than or equal to 6000 / mm < 2 >. The preparation method of the free-cutting complex cupronickel alloy comprises the technological processes of smelting, continuous casting, extrusion, multi-pass stretching and annealing, finished product stretching and low-temperature annealing. The free-cutting complex cupronickel alloy has the characteristics of excellent cutting performance, mechanical strength, stable color and luster and stress corrosion resistance.

The application relates to the technical field of laser additive manufacturing, in particular to a metal powder for laser additive manufacturing and a preparation method and application thereof. The chemical composition of the metal powder comprises Ni, Fe, Cr and Cu; the content of the Fe is 3.0-5.0 wt%, and the content of the Cr is 10.0-15.0 wt%. The application solves the technical problem of high smelting cost of the existing cupronickel material, and improves the corrosion resistance and hardness of the cupronickel material.

This invention discloses a smelting method and equipment for continuous blowing and refining of cupronickel matte. The equipment includes a furnace body, within which a blowing zone is located. A feeding port is located on one side of the blowing zone. A refining oxidation chamber is located downstream of the blowing zone, and a refining reduction chamber is located downstream of the refining oxidation chamber. A copper discharge port is located on the other side of the refining reduction chamber. A main partition wall is provided between the blowing zone and the refining oxidation chamber. A first connecting hole is formed in the main partition wall, which obliquely connects from the bottom of the blowing zone to the middle of the refining oxidation chamber. This invention completes the blowing of copper matte and the pyrometallurgical refining of crude copper in one device, achieving continuous operation.

The application relates to the field of cupronickel materials, and particularly discloses a new type of cupronickel suitable for a MIM process and a forming process thereof. Metal powder raw materials include the following mass percentages: Ni 12-18%, Sn 0.6-1.0%, mixed lanthanum-cerium-praseodymium rare earth 0.6-1.0%, Cu 80.4-86.4%, and the balance of Fe and inevitable impurities. When the material is used as a whole, the oxidation resistance of the new material in a catalytic degreasing process can be significantly improved, and the material loss in a sintering process is also greatly reduced, so that the inherent shortcomings of traditional cupronickel are overcome, and various cupronickel products with complex shapes can be perfectly produced through the MIM technology.

This application relates to the technical field of auxiliary equipment for metallographic testing, specifically an automatic grinding device for cupronickel metallographic testing samples, comprising: a housing, a base plate, a reversing mechanism, an upper grinding mechanism, a lower pressing mechanism, an adjusting mechanism, a connecting mechanism, a positioning mechanism, and a control module; the lower grinding mechanism is set inside the rectangular housing, and the lower pressing mechanism, which can be adjusted and maintain its adjusted position, enables the change of the position of the connecting mechanism; the reversible reversing mechanism, in conjunction with the upper grinding mechanism, can adjust the pressure and grinding speed, and the left and right sides can work independently, achieving better sample grinding and a better grinding effect; furthermore, this application also has the advantages of increasing the grinding speed of large batches of cupronickel samples under stable operation, simple operation, and reduced equipment use and maintenance costs.