| A device and it's controlling system for a new efficient rheocasting process, termed Low Superheat Pouring with a Shear Field(LSPSF), is developed. The effects of LSPSF parameters on the microstructure of aluminum alloys semi-solid slurry were studied. The application and developing trend of IPM (Intelligent Processing of Materials) in the technology of semi-solid process is intruduced. Accord to the concept of IPM, a temperature controlling system based on Fuzzy control and PC controlling technology was developed. The relation between electrical conductivity and microstructure of semi-solid alloys was investigated. The main work and results presented as follows:(1) In order to improve the precision and stability of LSPSF process, a temperature controlling system based Single Chip Micyoco and PID technology was developed. The higher precision(around±1℃) and facility of the system are important and efficient to the LSPSF process.(2) A series of experiment using aluminum alloys of ZL101, ZL201, A380 were carried out to studied the effects of the LSPSF parameters on the microstructure of aluminum semi-solid slurry. The results are as follows:Under the condition which only when the pouring temperature and the rotation speed of duct matching well, it can be carried out that the LSPSF process has high efficiency of duct making with high quality of microstructure. It's concluded that the choiceness condition of LSPSF process is:(a) The rotation speed of duct is around 100±10r/min;(b) The pouring temperature is around 30±10℃above liquidus temperature;(c) The temperature of slurry container is around 500±50℃.(3) The conception, principle and key technology of IPM (Intelligent Processing of Materials) are introduced. Considering the specialty of semi-solid process, a viewpoint is brought forward in the paper that the application of IPM on semi-solid technology should start with two directions: technology of simulation and forecast, technology of process intelligent controlling. The main viewpoint presented as follow:(a) The keystone of the application of IPM on semi-solid process is new sensor researching and modern controlling technology applying.(b) According to the speciality of semi-solid technology, the sensor can reflect the performance of microstructure of slurry with non-contact checking on the manufacturing line.(c) The controlling system based on the PC control should be developed for semi-solid process, which applying the modem intelligent controlling theory.(4) According to the viewpoint above, a intelligent temperature controlling system using fuzzy control theory based on PC is developed. Using kingview6.5, the system software is designed. Through the simulation and the experiment, the result shows that the new temperature controlling system have high quality of temperature controlling. The precision(around±1℃) and stability are all better than the system based PID controlling.(5) The relation between electrical conductivity and microstructure of ZL101 alloy and A380 alloy is studied. The important parameters of microstructure which affect the electrical conductivity is the solid phase ratio, equivalent diameter, shape factor. A conclusion is brought out as:(a) The electrical conductivity of aluminum show itself a trend of increasing along with the solid phase ratio increasing.(b) The electrical conductivity of aluminum show itself a trend of increasing along with the equivalent diameter increasing.(c) The electrical conductivity of aluminum show itself a trend of increasing along with the shape factor increasing.Using the Sn-15wt.% Pb alloy, the affect on the electrical conductivity of different temperature between the semi-solid temperature range, and different time of isothermal heat-treatment is studied. The conclusion presented as follow:(a) When the isothermal time keeps invariable, the electrical conductivity of Sn-15wt.% Pb alloy show itself a decreasing trend along with the isothermal temperature increasing between the semi-solid temperature range.(b) When the isothermal temperature keeps invariable, the electrical conductivity of Sn-15wt.% Pb alloy show itself a increasing trend along with the isothermal time increasing.According to this conclusion, the electrical conductivity can be used to control the quality of microstructure of semi-solid slurry.
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