30results about How to "Guarantee metallurgical quality" patented technology

The invention provides gray cast iron and a smelting method of the gray cast iron, and relates to the technical field of metallurgical materials. The gray cast iron is prepared from nonmetallic alloyelements, metal alloy elements and the balance iron and inevitable impurities, wherein the nonmetallic alloy elements comprise, by mass, 2.8-3.2% of C, 2.2-2.4% of Si, 0.2% or less of P, 0.15% or lessof S, the metal alloy elements comprise, by mass, 0.25-0.35% of Cr and at least one of Mn, Cu, Mo, Li, Sn and Sb, and the total content of the metal alloy elements except for Cr is 1.5-1.6%. According to the gray cast iron, by reasonably designing the chemical ingredients, the gray cast iron can meet performance requirements of machine tool basic parts, waste iron and waste steel can be adopted as main furnace materials, therefore, raw material selection and matching flexibility are improved, and the raw material cost and the production cost are reduced.

The invention belongs to the technical field of casting, in particular to an electromagnetic semi-continuous casting device for alloy ingots with high casting stress and an ingot casting method using the device. The electromagnetic semi-continuous casting device mainly includes a shunt, a mold and a dummy head, and the mold includes a mold inner sleeve, a cold water tank, a coil and a bottom bracket. Under the condition that the amount of cold water is constant, a cold water tank with double rows of different-diameter cross water holes is used to make the first cold water appear double water streams, thereby reducing the cooling rate of the alloy melt at the contact point between the first cold water and the inner sleeve of the crystallizer , thereby reducing the chance of cracking. Through the setting of the distance between the double drainage holes, the cooling intensity during casting can be controlled, which helps to improve the surface quality of the ingot. The use of the diverter groove in the device of the present invention can also effectively reduce the temperature gradient and casting stress at the center and edge of the slab, thereby reducing the possibility of cracking of the ingot. The electromagnetic semi-continuous casting device in the present invention can also realize the production of products within a certain specification range by changing the specifications of the mold inner sleeve.

The invention discloses a method for reducing segregation of a high-iron composition titanium alloy casting ingot. The method comprises the following steps that 1, 0-grade sponge titanium, Al-V-Fe, Ti-Fe, aluminum shots and TiO2 are used as raw materials, and the weights of the required raw materials are weighed according to the component proportion of a titanium alloy; 2, the 0-grade sponge titanium, the Al-V-Fe, the aluminum shots and the TiO2 are mixed uniformly to obtain a preliminary mixture, and the Ti-Fe component is wrapped into an alloy wrapping strip through an aluminum foil; and then an edge inverse segregation distribution method is adopted for distribution; 3, an oil press is used for pressing to obtain a single electrode block; 4, the single electrode block is welded to obtain an overall consumable electrode; and 5, the overall consumable electrode is dried, and the casting ingot is melted. According to the method for reducing segregation of the high-iron composition titanium alloy casting ingot, an edge inverse segregation distribution manner is adopted to an easy-segregation alloy, the problems that the titanium alloy containing easy-segregation elements is uneven in smelting constituent, easy to segregate and the like are solved; and during melting, the manners of the large magnetic field and the small current are adopted to ensure the metallurgical quality ofthe casting ingot.

The invention discloses an inert atmosphere control device for laser forming and repair. A return air duct (13) is sequentially connected in series with a three-way valve (2) of an exhaust pipe, a dust filter (3), a diaphragm booster pump (4), a pressure gasholder (5), a three-way valve (7) of an air inlet pipe, a dehydrator (8), an argon purifier (9) and a water cooling jacket (10); an air intake pipeline (11) of the water cooling jacket is connected with a water cooling unit (10) and an atmosphere protective cover (1); an exhaust air duct (14) is connected with the three-way valve (2) of the exhaust pipe; both ends of an air intake duct (15) of the air storage tank are respectively connected with the three-way valve (7) of the air inlet pipe and the air intake pipeline (11) in a sealing way; and both ends of an air supplement pipeline (16) are respectively connected with a gas bottle (6) and the pressure gasholder (5). The invention causes work air in a laser forming and repairing process to be cyclically utilized, reduces use and exhaust of argon, saves the running cost, controls contents of oxygen and nitrogen up to 10 ppm in a working process, and ensures the quality of the laser forming and repair.

The invention relates to a blade pouring technique, and particularly relates to a pouring technique of a directional turbine blade with a block cast cover board structure. According to the technical scheme disclosed by the invention, the pouring technique of the directional turbine blade with the block cast cover board structure is as follows: alloy liquid is poured in a high-temperature state, and crystal is pulled in a low-temperature state. The invention provides a pouring technique of a directional turbine blade with a block cast cover board structure, the impact force on a ceramic core and a glass tube caused by the alloy liquid is reduced, the problems of deviation, leakage and breakage of the ceramic core and the glass tube in the pouring process are avoided, the metallurgical quality of the blade is ensured, and the qualified rate of precision casting is increased.

The invention relates to a preparation method of a neutron-absorbing composite material with a high neutron absorption rate, the steps of which are as follows: (1) weighing 8-40 parts of boron carbide powder, 32-96 parts of aluminum alloy powder and light rare earth in parts by weight 0.1-10 parts of powder; (2) Add boron carbide powder, aluminum alloy powder and light rare earth powder to the powder mixing equipment for mixing; (3) Put the materials evenly mixed by the powder mixing equipment into the vacuum sintering furnace for sintering Obtain the slab; (4) cast a layer of aluminum alloy layer with a thickness of 0.05-1cm on the four side walls of the slab and then mold it; (5) carry out 3-8 passes of hot rolling after the molding. After annealing at 450-500°C, the neutron-absorbing composite material with high neutron absorption rate can be obtained, which ensures the metallurgical quality of the material and ensures that the composite material has excellent mechanical properties, thermal conductivity and neutron absorption capacity.