Thermal Analysis System Of Al-Si Alloy Modification Effect

Aluminum-silicon alloys are widely used aluminum alloy due to their excellent casting and mechanical properties.This paper develops a thermal analysis system to forecast the modification effects of hypoeutectic Al-Si alloys.The thermal analysis system consists of hardware and software.The hardware includes thermal analysis data acquisition cards and sample cups.The software part is written in C language,and QT is designed as a program framework.The characteristic value of the cooling curve is obtained by data acquisition?temperature?,numerical filtering and differential processing..After a large number of experiments,the metallographic structure and the mechanical properties of the alloy are compared with the characteristic values of the thermal analysis system,and obtain the criterion for the metamorphism of the hypoeutectic Al-Si alloy,which can verify the accuracy of the thermal analysis system.The thermal analysis of ZL104 alloy and 702A alloy is carried out in this paper.The study of ZL104 alloy show that when the addition amount of Sr is 0.06%⁰.07%,the eutectic temperature drops sharply,the?T_ERR reaches the maximum in the test,metallographic analysis is good,and the mechanical properties are the best.Therefore,the optimum amount of Sr for the ZL104 alloy to achieve the best modification effect is 0.06%.The eutectic time t_e and?T_ERR of the eigenvalues are used to determine the metamorphic effect of the ZL104 alloy,and a polynomial relationship between the?T_ERR and the metamorphic grade is established.ML=-0.1327×?T²_ER+1.5976×?T_ER+1.0231The study of 702A aluminum alloy show that the?T_ERR can also be used as a criterion for the modification effect of the 702A alloy.The characteristic value t_e is influenced by the alloy composition.Therefore,only the?T_ERR is used as a criterion for judging the effect of alloy modification.After the metallographic and mechanical properties test,the optimum adding amount of the 702A aluminum alloy to achieve the best modification effect of Sr is 0.08%.Finally,the paper establish the polynomial relationship between the?T_ERR and the modification level for ZL104 alloy and 702A alloy.ML=-0.0346×?T²_ER+0.977×?T_ER+1.2085...