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建立了铸件凝固过程热应力模拟的一维流变学本构方程，并且对一端受约束一端带热节的铸钢试棒进行了数值模拟，进而研究了热裂机理。模拟结果表明，随着凝固过程的进行，在热节处粘塑性（Ｂｉｎｇｈａｍ）体的应变急剧增大而弹性应变急剧减小。浇注温度和砂型初始温度越高，热节处粘塑性应变越大，而热应力越小。并且热节处表观粘度随凝固进行逐渐增大，在凝固末期急剧增大。因此粘塑性应变决定了热裂的产生，并且热裂发生在凝固末期。
The one-dimensional rheological constitutive equation of the thermal stress simulation of the casting solidification process was established. The cast steel test rod with one end and one end of the constrained heat-transfer section was numerically simulated, and then the thermal cracking mechanism was studied. The simulation results show that with the solidification process, the strain of the Bingham body rapidly increases and the elastic strain decreases sharply at the hot section. The higher the pouring temperature and sand initial temperature, the greater the viscoplastic strain at the hot joints and the lower the thermal stress. Apparent viscosity at the hot section gradually increased with the solidification and sharply increased at the end of the solidification. Therefore, viscoplastic strain determines the occurrence of thermal cracking, and thermal cracking occurred in the end of the solidification.