33results about How to "Reduce oxidation slag" patented technology

The invention belongs to the field of casting technologies and new materials and particularly relates to a high-strength high-tenacity cast-state QT700-10 and a production method thereof. Compared with ductile iron produced in the prior art, the high-strength high-tenacity cast-state QT700-10 has high strength and a high elongation rate, heat treatment is not needed, heavy metal, such as, Ni and Mo are not added in production, the tensile strength Rm in the cast state is larger than or equal to 700 MPa, the elongation rate A is larger than or equal to 10%, compared with the standard brand QT 450-10, the lowest tensile strength is improved by 55% under the same elongation rate; and compared with the standard brand QT 700-2, the lowest elongation rate is improved by four times under the same tensile strength. The high-strength high-tenacity cast-state QT700-10 can meet requirements of automobile ductile iron castings with high requirements for safety and comprehensive mechanical properties.

The invention provides an ultrahigh-strength and heat-resistant aluminum alloy and a preparation method, and the alloy aims at overcoming the defects of an existing heat-resistant aluminum alloy. Theultrahigh-strength and heat-resistant aluminum alloy comprises the following components in percentage by mass: 5.9-7.2% of copper, 0.60-1.50% of silver, 0.6-0.9% of magnesium, 0.1-0.5% of chromium, 0.1-0.5% of molybdenum, 0.09-0.3% of zirconium, 0.07-0.12% of scandium and/or 0.07-0.12% of erbium and/ or 0.07-0.12% of yttrium, and the balance aluminum, wherein the mass ratio of copper to magnesiumis 7-10. According to the ultrahigh-strength and heat-resistant aluminum alloy, the separating out of a strengthening phase in the alloy and the distribution are controlled by means of microalloying,deforming, thermal treatment and the like based on the abovementioned mixing ratio of the alloy, so that the density of the strengthening phase in the alloy is improved, and the alloy remains a largeamount of fine dispersed strengthening phases under high temperature, and as a result, the alloy strength and heat resistance are improved.

The invention discloses lead-free high-temperature antioxidant solder. The solder is prepared from the following ingredients by weight percent: 0.001 to 5.0% of silver, 0.001 to 11% of copper, 0.001 to 0.1% of nickel, 0.001 to 0.1% of indium, 0.001 to 0.15% of phosphorus, 0.001 to 0.08% of germanium and the balance of tin. The invention further provides a preparation method of the lead-free high-temperature antioxidant solder. Compared with the prior art, the lead-free high-temperature antioxidant solder can generate little oxidizing slag at high temperature (250 DEG C to 510 DEG C) soldering and can keep the surface of a solder machine bright and free of oxidation at the temperature. The solder can't be oxidized for 50 seconds at the temperature of 500 DEG C, so that the soldering efficiency is greatly improved and the high temperature oxidization resistance is excellent. In soldering, the solder has fewer soldering defects compared with an ordinary Sn-Ag-Cu system, the surface of a solder joint is bright, the solder joint is full, continuous soldering is avoided, and the soldering quality is effectively improved. The solder is environmentally friendly and safe.

The invention discloses a mold filling differential pressure determining method based on vacuum differential pressure casting classified pressurizing mold filling. Under the condition that it is guaranteed that the inner mold filling flow state of a liquid ascending pipe is laminar flow, the mold filling pressure and the mold filling speed of liquid metal in the liquid ascending pipe are determined, and the classified pressurizing mold filling differential pressure needed at the position of a classified mold filling section is calculated in combination with the shape, the height, the wall thickness and the complex degree at the position of a casting mold filling section according to the principles of energy conservation, mass conservation and continuity. The mold filling differential pressure determining method has the advantages that a good mold filling flow state in the liquid ascending pipe can be guaranteed, the classified pressurizing mold filling differential pressure is determined according to the mold filling section feature, and accordingly, the stability of the mold filling flow state at the position of the mold filling section can be obviously improved. The vacuum differential pressure casting classified pressurizing mold filling differential pressure can be scientifically determined, and important significance is achieved for achieving stability and the sequence ofthe flow state in the mold filling process and reducing oxidization slag inclusions, gas wrapping and other casting defects happening to castings.

The invention belongs to the technical field of copper alloy machining, and relates to a covering agent applicable to smelting of a copper alloy containing easily oxidized alloying elements, and application of the covering agent. The coving agent consists of the following components in mass percent: 50-80% of sodium borate and 20-50% of cullet, wherein the sodium borate and the cullet are added respectively, and the cullet is added firstly, and then the sodium borate is added with the time interval not less than 10 min. Through the covering agent, vacuum smelting can be replaced by common smelting, the copper alloy containing easily oxidized alloying elements can be smelted by a common electric induction furnace, large-size ingot castings can be easily prepared and continuously cast, and the alloy quality of the copper alloy subjected to smelting is better. The covering agent related to the invention has the characteristics of low cost, environmental protection and energy conservation.

The invention relates to an open type heating and heat preservation hopper for reducing oxide inclusions and a pouring method. The problems that in the prior art, the oxide inclusion defect of a casting poured by a hopper for tilting casting is serious, and the heat preservation effect of the hopper is not ideal are solved. The open type heating and heat preservation hopper comprises a hopper outer lining, a hopper body and a pouring cup; a cavity with an opening in the top is formed in the hopper body, and the cavity is sequentially divided into a liquid inlet cavity and a liquid containing cavity according to the flowing direction of molten metal; by designing the shape of the cavity wall of the liquid inlet cavity and the shapes and the sizes of a liquid inlet and a liquid outlet, it is ensured that the liquid inlet cavity is approximately filled with the molten metal in the flowing process below the pouring cup, and meanwhile it is ensured that the molten metal stably enters the liquid containing cavity; by designing the structures and shapes of a pouring gate and the liquid containing cavity, the stability of the process of filling a casting mold cavity with the molten metal is guaranteed; by using the open type heating and heat preservation hopper for pouring, the oxide inclusion defect of the casting can be effectively reduced, the temperature of the molten metal in the open type heating and heat preservation hopper can be maintained in the pouring process, the heat loss of the molten metal in the hopper is reduced, and the quality of the casting is ensured.

The invention provides a knotting type heat preservation furnace used for continuously preparing aluminum alloy semi-solid slurry. The knotting type heat preservation furnace comprises a furnace body,a hearth and a heater; the hearth and the heater are located in the furnace body, the heater is arranged on the top of the hearth, a slurry making groove is formed in the bottom of the hearth, the heater heats molten aluminum in the hearth through heat radiation, the temperatures of the molten aluminum in the hearth forms a temperature gradient gradually reduced from the molten aluminum liquid level to the molten aluminum deep position, and semi-solid slurry is generated in the slurry making groove. The furnace is used for continuously preparing the semi-solid slurry, oxide inclusions in theslurry are few, and quality inside the casting can be further improved; the slurry making groove in the furnace body is large in use depth, the molten aluminum utilization rate can be up to 80% or above, molten aluminum is added, slagging off is conveniently operated, the effect on the prepared slurry is very little, and the normal production is not affected.

The invention discloses a smelting method of a zinc alloy. The smelting method comprises the following steps: taking 99.0%-99.35% by weight of a Zn-Al4 alloy, 0.55%-0.9% by weight of an AlTi-5B intermediate alloy and 0.05%-0.15% by weight of ZnCl2 as raw materials for smelting; a power frequency coreless induction furnace is used as smelting equipment; a zinc liquid pump, a silicon carbide ceramic infusion tube with the output hole diameter of 45-50 mm and an H13 steel crucible serve as smelting tools, and the zinc alloy is manufactured through the three steps of raw material and equipment preparation, pre-preparation and smelting. The method is low in metal loss, controllable in cost, small in pollution, good in compactness and good in uniformity.

The invention relates to a process and a device for welding magnesium alloy sheets. The magnesium alloy sheets are protectively welded by the aid of mixtures, and the mixtures comprise, by volume, 70-80% of argon and 20-30% of helium. The process includes controlling pressure gauges at openings of an argon tank and a helium tank during welding and filling the 70-80% of argon and the 20-30% of helium into a gas mixer; selecting grooves of a welding platform according to the lengths of weld joints of magnesium sheets; opening gas inlet pipe valves corresponding to the selected grooves during welding, closing gas inlet pipe valves corresponding to the unselected grooves, butting the magnesium sheets to the upper sides of the selected grooves and welding the magnesium sheets after 5-second gas filling time elapses. The lengths of the selected grooves are larger than the lengths of the weld joints by 10-30mm. The process and the device have the advantages that the degree of welding fusion and the surface quality can be improved, the shortcoming of oxidation of back surfaces of magnesium alloy sheets can be overcome, oxidation conditions of welding spots and surrounding materials of the welding spots can be improved, oxidation slag inclusion due to oxidation can be reduced, and the tensile strength of welded magnesium alloy can be improved.