The Development Of Foundry Thermal Analysis System At Low Cost

The thermal analysis is an energy analysis which can record the metalphase transition and cooling curve during solidification. This method canevaluate the quality of the metal melt simply, fast and accurately, which have agreat significance to improve the casting quality and reduce production costs.The product of the thermal analyzer and sampler sold at higher prices, and hinderthe promotion of thermal analysis techniques. In this paper, a modular, multi-channel, high-precision thermal analysis system and a new kind of sampler withsimple and low cost production was designed, which reduce the cost ofprocurement and testing of thermal analysis equipment effectively.Firstly, the temperature compensation module and signal amplificationmodule is designed and the signal acquisition module suitable for thermalanalysis is selected. The software portion of the thermal analysis systemdeveloped as a tool to visual basic6.0. High speed, multiple-channels andsynchronized acquisition was available, the acquisition process could bemonitored. Filtering was implemented by calculating average and medial value,which reducing the interference of the environment on the data collection process.The segmental least square linear fitting for thermocouple index improved theconversion speed and accuracy between thermal electric potential andtemperature. The characteristic values were identified by both means of mathmodel and artificial cognition, which complement each other. The performancewas avail to identification accuracy. The factors affecting system’s accuracy wereinvestigated, and system accuracy was tested according to the experiments ofthermal analysis with pure aluminum. The results indicated that the repetitivenessof data measuring and anti-noise ability were high.A complex thermal analysis sampler designed which composed of innercovering and outer covering. Inner covering made by dry clay sand and can be produced by the users themselves with the special mold. The outer coveringwhich made of45steel can be used multiple times. Choose right dimension ofsampler by Computer simulation of cooling curve and test sampler of differentdimension. Compared with the commonly used materials of sampler such as resinsand, ceramic, graphite and metal this new type of sampling has a lower thermalconductivity, higher test temperature and lower cost.The effect between Composite sampler and TECTIP sampler is basically thesame. The level of metamorphism of ZL101were predicted using the thermalanalysis system, the results were consistent with the metallographic observations.Spherodization of QT450alloy were predicted by this system, the results wereconsistent with the metallographic observations.