Semi-solid electromagnetic stirrer @idea hebei

               Technical principle                In the ordinary course of casting, primary crystal grew up in dendritic manner, when solid rate around 0.2, dendritic crystal to form a continuous network skeleton, loss the macro liquidity. If get strong stirring when the liquid metal from liquid phase to solid phase in the process of cooling, make the casting is easy to form the branch crystal network skeleton in normal be broken and retains the dispersed particle morphology, suspended in the surplus liquid phase. This kind of granular non-dendrite microstructural, in steady rheological aspect in 0.5-0.6 still has certain rheology, which can use conventional forming process, such as die casting, extrusion, forging and metal forming.                                      Outlook             Although the semisolid continuous casting technology haven't reached the level of large-scale industrial application, But in the existing experimental research and small-scale production has shown a strong vitality. Synthesizing the relevant research both at home and abroad is not hard to see, semi-solid casting technology in the following areas has a bright application prospect:                  (1) High alloy and difficult deformation material forming                  High alloy materials and difficult deformation material forming has been a difficult problem in the field of material processing. The semisolid continuous casting billet in the semi-solid temperature has the similar advantage of the liquid molding directly, for high alloy material no segregation, no defects casting and difficult deformation material forming smoothly found a feasible technical route. The research team researches show that, usually think not of forging white iron and high manganese steel, After made of semi-solid casting billet, in the semi-solid temperature molding thickness 2 mm, a length of more than 100 mm complex parts. Therefore, the semisolid continuous casting in terms of difficult deformation material molding with billet production will have a brilliant future.               (2) The development of a new generation steel and iron material                Now all countries in the world in the super steel research, our country also has been started important basic planning project“A new generation of iron and steel materials research”. A new generation of iron and steel material requires high clean, ultrafine, ultra-high strength, at the same time also has the potential of large scale application. In order to achieve this goal, will need to adopt continuous casting technology to made blank, while the existing continuous casting billet are widespread columnar crystal area is big, the macro segregation seriously flawed. The semisolid continuous casting billet tiny grains, less of macrosegregation advantage will no doubt be less for a new generation of iron and steel material blocking a worth exploring the technical route.                    (3) Composite material blocking and molding                 Composite materials are a rookie of materials science, but so far, the preparation of composite materials and its large-scale timber is still a problem. The semisolid continuous casting in solve this problem will have a brilliant future, It has been confirmed by numerous test institute.                In a word, The semisolid continuous casting technology in high alloy material, difficult deformation, fine crystal homogenizing steel materials and high value-added new materials forming has a unique technical advantages.                                 Semi-solid die casting technology and product advantages             Technics predominance              1)Without any grain refining agent can obtain fine grain structure, eliminates the traditional rough casting of columnar crystals and dendrites.               2)Forming temperature is low (Such as aluminum alloy can reduce more than 1200 °C), can save energy.              3)Die longevity is longer. Solid and low temperature of semi-solid slurry forming shear stress, is smaller than traditional dendrite size three orders of magnitude, therefore, smooth filling, heat load is small, thermal fatigue strength degradation.                4)Reduce pollution and unsafe factors. When working it get rid of the high temperature liquid metal environment.              5)Resistance to deformation is small, use smaller force can achieve homogeneous processing, forming the difficult-to-machine materials is easily.             6)Solidification speed faster, productivity higher, the process cycle shorter.            7)Suitable for using computer aided design and manufacturing, enhance the automation of the production.       product superiority               1)A high quality. Due to the grain refinement, microstructure Distribution Homogenize, reduce body contraction, cracking tendency to decline, eliminated shrinkage tendency on the base, mechanical properties increase significantly.             2)Closed narrowing of solidification, so the molding body size precision is high, machining allowance is small, near-net forming.             3)Forming alloy is wide. Nonferrous alloy are aluminum, magnesium, zinc, tin, copper, nickel base alloy; Iron base alloys such as stainless steel, low alloy steel.             4)Manufacture of metal matrix composite materials. Use high viscosity of semi-solid metal, make the density difference, small solid solubility of metal alloys, also can effectively make mixing different materials, making a new composite materials.