31results about How to "Dendrite refinement" patented technology

The invention relates to an electroslag smelting casting method of fixed blades of a water turbine. Consumable electrodes are prepared by adopting a voltaic arc furnace refining method and the fixed blades are prepared by adopting an electroslag smelting casting process through a mould. The chemical components of the consumable electrodes are controlled as follows: C is 0.14-0.19 percent, Si is less than or equal to 0.6 percent, Mn is 1.5-1.9 percent, P is less than or equal to 0.035 percent, S is less than or equal to 0.035 percent, V is 0.02-0.15 percent, Nb is 0.015-0.06 percent, Ti is 0.15-0.25 percent, Al is more than or equal to 0.015 percent, O is less than or equal to 0.0040 percent, N is less than or equal to 0.0080 percent, H is less than or equal to 0.00035 percent, and the balance is Fe. The electroslag smelting casting system and the electroslag guide are controlled as follows: CaF2 is 60-80 percent, Al2O3 is 40-20 percent, or less MgO and CaO (the total is less than or equal to 20 percent); and the electroslag amount is usually 1.5-5 percent of the weight of a casting. The invention has less amount of oxide and sulfide, small size, even distribution, clean casting base body, high cooling speed, large crystallization temperature gradient at the front of solid and fluid, compact casting texture, high size precision and little distortion, and can greatly improve the product property of the refined casting.

The invention relates to the manufacture field of impact type rotating wheels, and in particular relates to an electroslag fusion casting manufacture method of rotating wheel blanks of an impact type hydraulic generator. The electroslag fusion casting manufacture method is an electroslag fusion casting technology for impact type rotating wheel integral casting blanks and individual rotating wheel water tank blanks. According to the method, self-consumable electrodes and the electroslag fusion casting technology are adopted; the rotating wheel integral casting blanks are produced by rotating wheel integral casting circular type blank crystallizers under an integral structure or an individual combined structure; and the individual rotating wheel water tank blanks are produced by rotating wheels water tank crystallizers under the integral structure or the individual combined structure. With the adoption of the method, the shortcomings of the current production technology of high water head impact type rotating wheel blanks can be solved; the near net forming impact type rotating wheel integral casting blank manufacture technology and the individual rotating wheel water tank blank manufacture technology are adopted; the produced rotating wheel blanks and the water tank blanks are high in fatigue resistance, high in crack generation and expansion resistance, long in service lives and high in use safety; and the quality and performance of the produced rotating wheel blanks and the water tank blanks are in line with those of forged blanks obtained by using the same materials; and the method has the advantages of low production cost, short production period and the like.

The heat resistant no-aluminum die cast Mg-RE alloy consists of Y 2-4 wt%, Gd 0.2-0.6 wt%, Zn 0.3-0.6 wt%, Mn 0.1-0.3 wt%, and Mg for the rest. Y as the excellent additive for raising the performance of Mg alloy can refine the dendrite crystal in the alloy, increase the rate of fiber structures in alloy fracture and raise the plasticity of the alloy; and Gd and Zn serve as the alloy reinforcing elements too. The heat resistant no-aluminum die cast Mg-RE alloy has excellent room temperature mechanical performance, high temperature mechanical performance superior to that of AE44 alloy, and excellent creep resistance in the conditions up to 250 deg.c and 30 MPa.

The invention relates to a preparation method of Mg-Zn-Ca series biomedical magnesium alloy, and belongs to the technical field of batch preparation of biomedical degradable magnesium alloy. The method comprises the steps of burdening, smelting and solidification system preparation, alloy smelting and purification, undercurrent transfer injection and forced filtration, precise solidification control and waste heat homogenization, near solidus homogenization treatment and plastic deformation treatment. The low-cost preparation technology has the greatest advantages that the preparation of a Mg-Zn-Ca series biomedical magnesium alloy ingot blank with the high thermal cracking tendency and the cross section area larger than 70000 mm <2> is met, homogeneous clean casting of industrial scale isachieved, and therefore the production efficiency can be greatly improved, the deformation degree is increased, and the performance is improved; and meanwhile, the cracking risk of a large cast ingotis greatly reduced, homogenization of a pasty area and a liquid phase area is achieved, the nucleation rate is increased, dendritic crystals are refined, and meanwhile specific gravity segregation and reverse segregation of Zn are effectively avoided.

The invention relates to the field of electroslag smelting casting production of turbine runner blade castings, in particular to a turbine runner three-dimensional curved surface blade electroslag smelting casting direct forming method. Electroslag smelting casting is used for completing secondary refining purification and casting near net forming of consumable electrode materials. The specific process comprises the following steps that 1) the structure form of a casting blank crystallizer is of an assembled type or a split type; 2) consumable electrodes in the smelting casting process consistof two parts, namely the fixed electrodes and the movable electrodes; and 3) a power supply mode adopts an alternating current single-electrode series loop and double-electrode series loop mixed power supply mode, by means of a power loop formed between double-electrode series electrodes, the slag layer temperature of an electroslag smelting casting area is increased, the metal fluidity of the area is improved, the solidification speed of the area is controlled, and blade smelting casting forming is achieved. The technology provided by the invention is applicable to manufacturing of the castings of tubular turbine generator runner blades or mixed-flow turbine generator runner blades or axial flow turbine generator runner blades.

An electroslag casting technology for manufacturing the wheel axle of high-speed train includes using the water bottom tray of crystallizer as electrode, using the axle billet as consummable electrode, choosing slag system and filling ratio, and electroslag casting. Its advantages are high mechanical performance and long endurance life.

The invention relates to a high-damping Mg-Mn-Ce-Al-Zn-Y alloy which comprises the following alloying element components, distributed in an alloy, in percentage by weight: 1.3-2.2% of Mn, 0.15-0.35% of Ce, 0.1-0.3% of Al, 0.25-0.55% of Zn, 0.5-1.5% of Y and the balance magnesium and inevitable impurities. The high-damping Mg-Mn-Ce-Al-Zn-Y magnesium alloy is prepared by the following process: adding the alloy elements in proportion, smelting and ingoting the alloy elements in vacuum, and carrying out water quenching on the smelted alloy to the room temperature, thereby obtaining the high-damping magnesium alloy. According to the process, by virtue of the synergistic effect in many ways, the alloy has relatively high damping capacity and very good plasticity. The damping capacity (Q<-1>) of the material prepared by the alloy can reach 0.2 at a room temperature when strain is 10<-3>. The preparation method is simple in process, is strong in transportability, is easy to operate, and is low in cost, so that the room-temperature damping capacity of the alloy is remarkably improved, and the applied range of the magnesium alloy is expanded.

The invention discloses a forming process for outdoor high and low parallel bars. The forming process is simple and easy to implement, the processed parallel bars have good performance and high safety, the service life can be prolonged, and the cost is lowered.

The invention discloses a fitness entertainment rowing machine which comprises a rowing machine body, a computer, a display screen and a power module. A pull wire is arranged in the rowing machine body and formed by stranding seven pull wires, six pull wires surround the rest pull wire in the middle, the pull wires are closely fitted, and the pull wire comprises, in total weight percent of 100%, 0.4-0.5% of C, 0.5-0.7% of Si, less than or equal to 0.025% of S, less than or equal to 0.025% of P, 0.1-0.2% of Cu, 0.08-0.09% of Cr, 0.05-0.13% of Ca, 0.1-0.3% of Mo, 0.02-0.04% of B, 0.1-0.3% of Ti,0.1-0.2% of Mo, 0.01-0.02% of lanthanide rare earth and the balance Fe and unavoidable impurities. The invention further discloses a fitness safety balance roller treatment process which is simple and easy. A treated balance roller has good performances, the service life of the balance roller can be prolonged, and the cost can be reduced.

The invention discloses a safety balance roller for fitness. The safety balance roller comprises a bracket, an armrest, a rotary shaft and a roller. The safety balance roller is characterized in thatthe bracket and the armrest are made of the same material, and the surface of the armrest is provided with a protective layer; and the materials of the bracket and the armrest comprise C, Mn, Si, P, S, Mo, Ni, Cr, Ca, Cu, O, Ti, Al, B, rare earth and the balance Fe, and the protective layer comprises silicone-modified epoxy resin, a cold-resistant plasticizer, a heat stabilizer, zinc oxide, an antioxidant, polyvinyl chloride, glass flakes, a filler flame retardant and zircon powder. The invention further provides a treatment process of the safety balance roller for fitness. The treatment process is simple and easy to implement, the treated roller has good performance, the service life can be prolonged, and the cost is lowered.