Casting is one of the basic processes of modern mechanical manufacturing industry.. As a hot metal processing technology, casting is gradually developing in China.. Fang aluminum alloy forging said casting machinery is the use of this technology, the metal melting into compliance with certain requirements of the liquid and poured into the mold, by cooling solidification, clear the whole process have a predetermined shape, size and performance of the casting can be used to all the machinery and equipment, also known as casting equipment. A new casting technology, the forging of aluminum alloy can be seven aspects are the following: (1) the challenge to the lightweight, ultrastructural refinement and ultra thin wall of the. Many use sand casting is sand have appropriate fire resistance, sand make gas by ventilation, cheap, can be repeatedly used, sand, after all, is the original, but is still casting method of the mainstream. Usually the sand casting technology, sand (0.1mm) in the space below is not. It has always been a small casting of the teeth of the teeth.. The use of precision casting technology company Nakagawa produced Yinpan, the sound can be recycled. Noguchi company produce such as ant size castings, with 0.7 micron alumina powder shape by centrifugal casting, ant's eye appearance can also regenerate. This aspect of the development of the foundry will cause new demand. Thin wall is a center of the die casting and developed, is the use of high-pressure die casting. For example, the average 1.0mm audio box shell is made of 1200 tons die casting machine high-speed casting method. The thin wall will be in accelerated casting instead of sheet metal parts. The effective use of the core in the casting, so as to achieve the purpose of lightweight hollow. Such as the supercharger impeller past by gravity casting process, in die casting method with rotating metal core is developed by the method of hollow impeller. The use of die casting method instead of gravity casting thus can improve the benefit of the net type of the product.. (2) the overall shape of the complex shape component; the castings are generally used for the monomer objects, and have recently begun to develop the components of the complex shape. For example, the turbocharger and exhaust manifold pipe two kinds of castings are integrally, with heat resistance of high speed steel vacuum suction casting method and cast thin the wall thickness is only 2mm integral casting. (3) casting welding: so far can be welded of steel parts, recently cast iron in surface after decarburization process can also be welded. The exhaust manifold of automobile exhaust manifold and the welding of high speed steel pipe were welded together, and the welding structure of high speed steel tube was used to meet the burning temperature.. In the future to achieve the cheap, good performance of the purpose of manufacturing welding together process will also have the development of. (4) thixocast (semi molten casting) method for liquid solid casting with high pressure method in coexisting conditions. This technology is carried out in cast iron, and it is also carried out in the aluminum alloy.. Fang aluminum alloy forging said the benefit is not only low melting temperature, is also reflected in the: A, due to the presence of the solid phase solidification latent reduction so as to improve the production efficiency. B, the cooling rate, so that the microstructure of the organization and thus improve the intensity of. C, the shrinkage of the solidification and the quality of the casting. But there are also low mold life, forming poor and other aspects of the problem. This method is advantageous point is solidified by high pressure can be high strength and high reliability object, due to the cost but also can not be greatly applied in production, but in the foundry industry to this technology in the future will pay in the corresponding position. (5) RP (rapid prototyping), CAM technology rapid development of CAD, also bring a big impact on casting technology. For example, no wood and sand on the sample (prototype) for direct casting. This technique is basically based on the principle of printing (laser and inkjet). The laser sintering process of the coated sand with the use of the resin coated sand, laser sintering and the use of the ink jet type coating, also look forward to a new RP technology development. This technique can also be made into resin casting method with similar dewaxing technology is also in development. Direct cutting methods are also being studied..Due to high cost of mold casting dewaxing method, which is difficult for small batch production. The wax directly with the five axis machining center machining for manufacturing products are also in development. The vanishing modulus method has two kinds of methods for machining polystyrene in the model and foaming polystyrene.. The former is small, which is suitable for large. In particular, the latter relies on the significant progress of CAD and CAM technology. The large ductile iron casting of the pump with 12.3 tons of double suction pump is made of three dimensional CAD graphics, and the expanded polystyrene is machined in machining center, and the magnetic particles are cast into the industry.. For the use of low-carbon steel, such as high speed steel, the carbon of polystyrene must be coated with ceramic particles when it is cast.. (6) direction of development of the composite material. Since casting is molten metal, it is suitable for metal matrix composites. For example, the cylinder type of ceramic magnetic, fiber preform, in which the crevice immersed into molten metal and made of metal matrix composite cylinder. In the future, the metal matrix composites casting technology will have a great influence on it. (7) direction of development of functional materials. Nomag non magnetic cast iron, IMER steel casting is low expansion of functional materials. The recent thermal expansion materials needed for the semiconductor industry are also in the development of the iron. Metal composite foam metal, will also occupy a place. The brake system of the car is also a function of the iron castings, the attenuation of the cast iron can be conducive to the quiet environment of the car. |