Testing System Of Alloys' Transient Solidification Temperature Field

This article put forward the detailed project of collecting the data of Alloys' Transient Solidification Temperature Field, according to the characteristics of this process. The whole testing system includes testing model, testing circuitry and software for analysis the testing data. The testing model constructed a temperature field which can considered as a one-dimension one for the purpose of simplify the testing model. The testing model mainly consists of thermocouple-assembly, metallic mould and pressing-outfit. An overflow-outfit was designed on the mould and a restrictive outfit was designed on the pressing-outfit. The material of the pressing-outfit is the same to the casting module, and the depth of pressing down is depended on the restrictive outfit on the pressing-outfit. During the testing process, the alloy is melted and the casting module is heated to the temperature, which is 20 to 30 centigrade higher than the melting point of the alloy. The quick pressing down of the pressing-outfit to the surface of the melted alloy simulated the process of melted alloy's swift touch to the inner surface of the casting module. The restrictive-outfit on the pressing-outfit and the overflow-outfit on the casting module are to assure of the successful touch of the undersurface of the pressing-outfit to the surface of the melted alloy. The testing circuitry is used to collect the signals, which mainly consists of thermocouple cathode compensate Circuit, non-linearity and single chip data collecting circuit based on SCM and communicating circuit. To fulfill the needs of the model of the solidification temperature field and improve the precision of the testing data, the measuring system, there are 8 testing points included in the system. Every testing point has its own amplificatory circuit. We can select the numbers of the testing points and the positions of the testing points. The ADuC812 SCM is used in the measuring system, which is produced by the Analog Device corporation; the type of SCM consist of A/D transition module. The measuring circus used RS-232 interface to communicate with the computer. The software for the testing data's analysis mainly consist of testing data collecting module andtesting data analyzing module. The former aim at collecting tasting data, and the latter is used to analyze the cooling-curve of the alloy. Combined with the thermal Analysis Method, the conclusions of the analysis can give the data material for the alloy's surface casting solidification during the swift touch of the inner surface of the casting module. In addition, the testing project provide a good solution for the guidance of the production of the alloys', which are infected much by the cooling function of the inner surface of the casting module.