Papers by Keyword: Horizontal Continuous Casting

Abstract: Aluminum is the richest metallic element in the earth, the ingots cast by DC casting process are usually extruded into aluminum bars. When the final products do not require high strength, this process appears to be low efficiency and high cost. We try to design a new technology to cast aluminum bar by horizontal direct chill (HDC) casting process directly. An electromagnetic field is applied during the horizontal continuous casting of 6061 aluminium bar with a diameter of 30mm. The experimental results show the asymmetry of the sump can be overcome by electromagnetic field. Ingot with good upper and lower surface quality is obtained. The structure of ingot is refined and the angle between growth direction and horizontal direction becomes small with increasing casting speed.

Abstract: The authors investigated the mold electromagnetic stirring technology of horizontal continuous casting for CuCrZr alloys. Due to the oxidizability of the zirconium, the CuCrZr alloys are difficult to produce by continuous casting process. A short process for CuCrZr alloys material engineering is urgently needed. The mold electromagnetic field improved the surface of CuCrZr wire rod. The cast structure was also refined. With the help of mold electromagnetic stirring technology, CuCrZr wire rods were horizontal continuous cast. By using a set of suitable parameters, big weight wire rods with an excellent surface were cast. The CuCrZr wire rod possessed an average grain size of 1.5mm, and the columnar crystal proportion was less than 10%.

Abstract: In this paper, research on reducing oxygen content and crack in oxygen-free copper strip during horizontal continuous casting process has been taken. First, reform the original copper alloy smelting-holding-casting three stages process. Through developing melting and holding integrative furnace, combine melting process and holding process for one, reforming smelting holding-casting two stages process. Second, pick up and realize on-off valve technics on controlling flow or stop of undercurrents copper liquid. Third, analyze the cracks in oxygen-free copper billet with flakinessratio 6500/20mm. And finally determine reasonable cooling process parameters through experiments. The results shows when oxygen content ≤0.0004% and density rise to 8.94-8.95 g/cm3, the crack has been completely eliminated.

Abstract: Horizontal continuous casting (HCC) Al-18%Si alloy billets were prepared with the addition of fine-grained Al-18%Si as a master alloy. The influence of cooling conditions and this fine-grained structural materials addition on the microstructure and tensile properties were studied. The uniformity of the HCC Al-18%Si alloy billets was also analyzed. The results denote that the HCC Al-18% Si alloy billets showed finer microstructure and better mechanical properties after double cooling. Fine-grained structural material addition can effectively reduce macrosegregation and make both primary and eutectic silicon much finer. The ultimate tensile strength clearly increased with an addition of 15 percent fine-grained structural material compared to the HCC alloy with no addition of fine-grained structural material. However, a small decrease occurred after an addition of fine-grained structural material up to 30 percent.

Abstract: In the method that the oxygen-free copper strips are produced through undercurrent horizontal continuous casting-cold rolling process, there are some coarse grains, microscopic cracks, shrinkage, shrinkage and segregation defects in the oxygen-free copper strip billet, which debase the densities of the strip billet, and are the main reasons for rejected castings during machining operation. Through the orthogonal experiment of the technical factors in the casting process, the mapping model of artificial neural networks have been established using the data obtained in the experiments, which built the relationship among the densities of casting blank and technological factors. With the help of this model, the optimal casting conditions have been researched by using GA optimizations method and real experiments. The results show that micro-structure of castings was improved and the densities of the strip billets are enhanced.

Abstract: Study the horizontal continuous casting mold solidification heat transfer process is not only to optimize the structure of the mold so that it has a uniform stress field, to improve the quality of slab, to extend the mold life basis, and improve production efficiency and cost-effective method. Therefore, oxygen-free copper horizontal continuous casting process as the research object, the establishment of a level of TU1 billet continuous casting mold solidification heat transfer model for the simulation of oxygen-free copper horizontal continuous casting mold solidification and heat transfer process has laid a theoretical foundation.

Abstract: Copper tube produced by FA6502 copper alloy in a company of Wuhan appears shrinkage cavity in horizontal continuous casting, the graphite mold core which exerts stretching effects is easy to be snapped in production process. The reason why shrinkage cavity appears is found through large number of experiments and analysis. Then we adjust the component of FA6502 copper alloy, the quality of new copper alloy FA6506 is improved significantly. Furthermore, we find the reason why the graphite mold core is snapped in production process, FA6502 copper alloy’s shrinkage rate is too large in solidification. The compact power of the graphite mold core is too large to bear, too much resistance in pulling process is exerted so that the graphite mold core is snapped.

Abstract: Damping capacities of the annealed nodular cast iron dense bar produced by horizontal continuous casting were measured by Dynamic Mechanical Analyzer. The relation of damping capacities with vibration amplitude, frequency and temperature was analyzed to investigate the damping mechanism of the alloy. The results show that the damping capacities increase with increasing temperature and frequency. The internal friction spectra exhibits two internal friction peaks at about 40°C and 150°C and caused by Snoek relaxation and Snoek-Köster relaxation, respectively. The maximum damping capacity can be obtained at about 63Hz. The damping is positive amplitude-dependent, whereas critical amplitude exists where the damping increases dramatically. The temperature-dependent damping results from the superposition effect of point-defect damping, grain boundary damping and interface damping, while dislocation damping is predominant in the frequency dependent damping. The amplitude dependent damping can be interpreted by G-L theory.

Abstract: In this paper, a comprehensive three dimensional mathematical model is built to investigate the effect of electromagnetic stirring (EMS) on continuous casting process of copper round billet. The electromagnetic field is simulated by ANSYS software and the thermal-flow field is simulated by FLUENT software. The coupling between electromagnetic field and thermal-flow field is implemented by user-defined subroutines. The simulation results have good agreement with the experiment ones. The results show that electromagnetic frequency and current intensity have significant influence on the fluid velocity, temperature gradient and sump depth. The optimum current intensity and frequency are found to be 40A and 10Hz respectively.

Abstract: In the present work, the effect of electromagnetic field on the microstructure and the alloying agent distribution was investigated. Tin element was shown to have the tendency to be inversely segregated on the surface of tin bronze. The microstructures of the continuous cast tin bronze plates are coarse and inhomogeneous. The factory test parameters were determined according the simulated data. The flow behavior of the mercury to be stirred as well as the relations between the microstructure of plate blanks and the current parameters were analyzed. With an appropriate electromagnetic stirring, the inverse segregation of tin for C51900 alloy plant blank was improved by 80%, and the microstructure was refined from about 10mm to 1~3mm in grain size.