12results about How to "Increase subcooling" patented technology

The present application relates to the technical field of rail production process, in particular to a production method for improving wear resistance of channel rail for tram. After universal rolling, compressed air is applied to the channel rail for forced cooling in parts. In the first stage, supersonic air jet cooling is applied to the rail head tread, rail head running edge, rail head left side, rail lip and rail bottom to control the cooling speed of each part. In the second stage, supersonic air jet cooling is continuously applied to each part of the rail to control the cooling speed of each part. In the third stage, subsonic air jet cooling is applied to each part of the rail to control the cooling speed of each part, and then the rail is naturally cooled in air. The quenching effect of the channel rail tread and running edge is improved, the pearlite interlamellar spacing is refined, the rail strength and hardness are improved, and the channel rail has good wear resistance.

This invention provides a method for preparing tensile specimens of CoFeNi medium-entropy alloy under deep supercooling conditions. The deep supercooling process of this method is carried out using a high-frequency induction heating device and a combination of melt immersion and cyclic superheating. During the melting process, the alloy raw materials are placed sequentially in a quartz crucible from bottom to top according to their melting points, with glass cleaning agents added to the bottom and top layers. During melting, the vertical movement of the quartz crucible along the central axis of the high-frequency induction coil and the heating temperature of the high-frequency induction coil are controlled to sequentially melt and coat the alloy surface with the glass cleaning agent, melt the Ni metal raw material, and melt the remaining metal raw materials. After the alloy liquid is thoroughly mixed, it is cooled and solidified. This heating and cooling solidification process is repeated until a supercooling of 205K is achieved, producing a CoFeNi medium-entropy alloy ingot that meets the dimensions required for tensile testing. This invention features an easily controllable solidification process, mature technology, and minimal component loss.

This invention discloses a method for refining primary silicon in Al-Si alloys through synergistic modification with nano-ceramics based on laser additive manufacturing. The method involves uniformly mixing Al-Si alloy powder with TiB2 and Al2O3 nano-ceramics using a ball mill under inert gas protection to obtain a ceramic-reinforced nano-Al-Si alloy composite powder. This nano-ceramic-modified Al-Si alloy powder is then melted and solidified layer by layer using a laser powder bed melting and forming equipment to create the desired target part. In this method, during the solidification of the nano-ceramic-reinforced Al-Si alloy melt, Al2O3 nanoparticles, due to their similarity to the Si crystal structure and the existence of a good interfacial coherence relationship, act as heterogeneous nucleation sites for primary silicon, increasing the nucleation rate and refining the size of primary silicon. TiB2 nanoparticles, distributed at the solid-liquid interface, can to a certain extent prevent the diffusion and aggregation of Si atoms into Si-Si atom clusters, thereby inhibiting the growth of the primary silicon phase, promoting the regularization of the primary silicon morphology and refining its size, and effectively reducing matrix grain size, significantly improving the mechanical properties of the Al-Si alloy.

This invention provides a regenerative reverse Rankine cycle dual high-temperature heat pump system. The heat pump system includes: a first heat exchanger, a first compressor, a first regenerator, a second heat exchanger, and a first expansion valve. The first heat exchanger is connected to the first compressor via the first regenerator. The second heat exchanger is connected to the first compressor. The first expansion valve is connected to the first heat exchanger, and the second heat exchanger is connected to the first expansion valve via the first regenerator. By setting up the first regenerator, heat exchange is performed between the working fluid before throttling and before compression, thereby increasing the subcooling before throttling and significantly reducing throttling losses. At the same time, increasing the superheat at the outlet of the first heat exchanger avoids the damage to the compressor caused by wet compression due to ultra-high temperature dry working fluid, which helps to ensure the service life and high reliability of system components.

The invention discloses a method for refining 316L stainless steel grains based on a selective laser melting technology, and belongs to the technical field of metal material additive manufacturing. According to the method, Fe-C-B alloy powder is added, a Fe-B or Fe-B-Cr type compound is formed to serve as a heterogeneous nucleation core when the 316L stainless steel component is manufactured through selective laser melting, columnar crystal epitaxial growth is inhibited, and grain refinement is achieved. By means of the synergistic effect formed by Fe, C and B, the negative influence of the SLM technology on the 316L stainless steel forming process is avoided, the advantages of the SLM technology are fully exerted in the 316L stainless steel component forming process, accordingly, the 316L stainless steel component high in compactness and excellent in comprehensive performance can be formed only through SLM, the method is stable in process, low in crack sensitivity and high in yield, and the production cost is reduced. The method has remarkable advantages in the field of additive manufacturing of high-performance 316L stainless steel components.

An air-source heat pump system includes a compressor, a four-way reversing valve, a throttling device, an outdoor heat exchanger, outdoor piping, a distributor, a water-side heat exchanger, a first check valve, a second check valve, and a third check valve. The outdoor piping is connected to the four-way reversing valve and the throttling device, and is also connected to the cooling ends of the top, middle, and bottom heat exchange units. The heating ends of the top, middle, and bottom heat exchange units are connected to the branch interface pipe, and the main interface pipe is connected to the outdoor piping and the throttling device. The second and third check valves are located on the outdoor piping; the liquid outlet of the second check valve is connected to the throttling device, and the outdoor piping between the bottom heat exchange unit and the second and third check valves is connected. The liquid outlet of the first check valve is connected to the main interface pipe, and its liquid inlet is connected to the piping between the second check valve and the throttling device. During heating, the system improves the heat exchange efficiency of the outdoor heat exchanger; during cooling, it improves the subcooling.

This application discloses a vehicle refrigeration unit and its refrigeration system, belonging to the related technical field of vehicle refrigeration units. It includes an installation frame with a housing and an inner housing detachably mounted on both sides. An air outlet assembly is located at the top of the inner housing, and the assembly includes a vertically structured mounting plate. External and internal air outlets are respectively located on the two sides of the vertically arranged mounting plate. The beneficial effects of this application are: the refrigerant from the condenser is directly split. During this splitting, one path is throttled and cooled by a throttling device before entering the economizer, while the other path, the un-throttled mainstream refrigerant, enters the economizer. The two refrigerants undergo sufficient heat exchange within the economizer. The throttled, low-temperature refrigerant can more effectively absorb heat from the mainstream refrigerant, thereby significantly increasing the subcooling of the mainstream refrigerant. This results in a lower dryness and higher liquid ratio of the refrigerant entering the evaporator, leading to a higher cooling capacity per unit mass of refrigerant.

This invention belongs to the field of aluminum-based composite material preparation technology, and relates to a continuous casting and rolling method for preparing aluminum-based composite material strips. The method involves preparing a reinforcing preform with a thickness not exceeding the roll gap distance in the aluminum-based composite material strip. Before preparing the aluminum-based composite material strip, the casting rolls are water-cooled and run at a set speed. Molten aluminum is injected into the molten pool, and the liquid level is controlled to a set value. Throughout the preparation process, the molten pool liquid level is maintained at the set value. The molten aluminum cools and solidifies upon contact with the roll surface of the casting rolls. Under the casting action of the two casting rolls, an aluminum alloy strip is formed and continuously output from the lower end of the roll gap. During the preparation process, the reinforcing preform moves from top to bottom at a set speed and is immersed in the molten aluminum pool. The molten aluminum penetrates into and fills the interior of the reinforcing preform. The reinforced preform, filled with molten aluminum, gradually solidifies as it moves to the roll gap until it is completely solidified. Then, under the casting force of the two casting rolls, it undergoes rolling deformation to form the aluminum-based composite material strip.

This invention provides a method for preparing an aluminum-silicon-copper sputtering target. The method includes: (I) providing aluminum, silicon, and copper raw materials, and dividing the aluminum raw material into two parts; (II) melting one part of the aluminum raw material to obtain an aluminum melt, then adding the silicon and copper raw materials to the aluminum melt, and performing a first melting at a first temperature to obtain a primary alloy melt, adding the remaining aluminum raw material to the aluminum-silicon-copper alloy melt, and performing a second melting at a second temperature to obtain a secondary alloy melt; (III) sequentially degassing, refining, and slag removal from the secondary alloy melt to obtain a purified alloy melt; (IV) sequentially casting and cooling the purified alloy melt to obtain an aluminum-silicon-copper ingot; wherein the first temperature is higher than the second temperature. This invention solves the problem of Si element aggregation in high-purity aluminum-silicon-copper alloys and can avoid silicon segregation in alloy ingots.

This invention relates to a compact V-type condenser with a subcooling section, comprising a V-type heat exchanger and a condensing fan mounted above it. The V-type heat exchanger includes a heat exchanger 1 and a heat exchanger 2 arranged symmetrically and inclined. The V-type heat exchanger is divided into a heat exchange section near the condensing fan and a subcooling section away from the condensing fan. The refrigerant is connected through a manifold, which includes an exhaust manifold and a liquid collection manifold located in the heat exchange section, and a subcooling manifold and a return manifold located in the subcooling section. The refrigerant flows from the exhaust manifold through several heat exchange paths into the liquid collection manifold, then into the subcooling manifold, and finally into the return manifold through several more heat exchange paths. The subcooling section further subcools the already liquefied refrigerant. This invention, without increasing the condensing area, improves the internal heat exchange effect of the refrigerant simply by adjusting the refrigerant flow path, effectively increasing the utilization rate of the heat exchanger area, and has significant economic and promotional value.

A kind of composite manufacturing method of TC11 titanium alloy thin-walled cylinder, based on the idea of additive + welding composite manufacturing, according to the size and structure characteristics of workpiece, the complex shape part in thin-walled cylinder is prepared by selective laser melting, and the other part is prepared by machining of forgings.The additive + welding composite method is used to manufacture TC11 titanium alloy thin-walled cylinder, which solves the problem that the integration forming of large-size aerospace structure is limited by the volume of atmosphere cabin or vacuum chamber, realizes the optimization of processing resources, and takes into account the processing efficiency and material utilization.The addition of Cu and Mn powder promotes the composition of the solid-liquid front of the molten pool to be supercooled, thereby promoting the transformation of columnar crystal to equiaxed crystal, and equiaxed grains are obtained by additive manufacturing.The tensile strength of TC11 alloy after double annealing is 1285MPa, and the elongation is 9.5%.Laser welding method is used to realize the connection of additive manufacturing TC11 alloy and forged TC11 alloy, and the tensile strength of the welded joint is 1536.5MPa, and the fracture mode is plastic fracture.

A high-temperature material with high toughness and a preparation method thereof, relate to the field of metal precision casting, and aim to solve the problem of poor room temperature toughness of existing Nb-Si alloy materials.The expression of the material is Nb-16Si-20Zr-2C-xW, and the method comprises the following steps: firstly, weighing raw materials Nb, Si, Zr, C and W; secondly, pre-treating the surface of the raw materials, melting, and obtaining a cast alloy ingot; thirdly, placing the ingot in a non-consumable vacuum arc furnace with an ultrasonic device to perform ultrasonic-assisted melting, and obtaining an ultrasonic-state alloy ingot; fourthly, filling quartz sand, heat treating, and cooling to obtain a heat-treated alloy; and fifthly, polishing the surface of the heat-treated alloy to remove the oxide skin, and the preparation is completed.The present application combines ultrasonic-assisted solidification with heat treatment, and significantly improves the toughness of the alloy material.The present application is used for preparing a high-toughness alloy material.