The effects of pouring and mold temperatures on the fluidity and hot tearing susceptibility (HTS) of Al–3.5Si–0.5Mg–0.4Cu alloy were investigated by the spiral mold test and the constrained-rod casting mold test, respectively. Optical microscope (OM) and scanning electron microscope (SEM) were carried out for microstructure observation. The results showed that the flow length (L_f) of Al–3.5Si–0.5Mg–0.4Cu alloy increased with increasing pouring temperature (T) and mold temperature (T₀). Moreover, the functional relationship between the fluidity and casting parameters was obtained by fitting the fluidity data as: \( L_{f} \, = \, 60.9 \, + \, 1082.4\text{[}\Delta T/T - T_{0} \text{]} \). The hot tearing mechanism was analyzed by observing the microstructure of the hot crack, and the HTS of the alloy with the mold and pouring temperatures was discussed in detail. According to the research, to achieve a lower hot tearing susceptibility under better fluidity, the suggested pouring and mold temperatures are 740 °C and 200 °C, respectively.

分别通过螺旋结晶器试验和约束棒铸造结晶器试验研究了浇注和结晶器温度对Al-3.5Si-0.5Mg-0.4Cu合金的流动性和热撕裂敏感性的影响。进行了光学显微镜（OM）和扫描电子显微镜（SEM）的观察。结果表明，Al–3.5Si–0.5Mg–0.4Cu合金的流动长度（L _f）随着浇铸温度（T）和铸型温度（T ₀）的增加而增加。此外，通过将流动性数据拟合为，获得流动性与铸造参数之间的函数关系：\（L_ {f} \，= \，60.9 \，+ \，1082.4 \ text {[} \ Delta T / T-T_ {0} \ text {]} \）。通过观察热裂纹的微观结构来分析热撕裂机理，并详细讨论了合金随铸型的热变形和浇注温度。根据研究，为了在更好的流动性下获得较低的热撕裂敏感性，建议的浇注温度和模具温度分别为740°C和200°C。