A thermomechanical model is developed to predict the temperature, degree of crystallization, residual stress, and strain in the selective laser sintering process for polymeric powder. Especially, a transient heat transfer model is used to calculate the temperature evolution. An elastic–viscoplastic model is developed to describe the temperature- and time-dependent stress–strain behavior of polymeric materials with crystallization-induced strain being included. A crystallization model is used to predict the relative crystallization degree during the cooling process. The sintering process and cooling process of polyamide 12 are simulated using the developed model. The melt pool depth and the deformation of the printed parts are validated by the experimental results. The evolutions of the temperature, relative degree of crystallization, strain, and stress are evaluated. The effects of the cooling rate on the strain and stress evolutions are discussed.

开发了一种热机械模型来预测聚合物粉末选择性激光烧结过程中的温度、结晶度、残余应力和应变。特别是，瞬态传热模型用于计算温度演变。开发了一个弹性-粘塑性模型来描述聚合物材料与温度和时间相关的应力-应变行为，其中包括结晶诱导应变。结晶模型用于预测冷却过程中的相对结晶度。使用开发的模型模拟了聚酰胺 12 的烧结过程和冷却过程。实验结果验证了熔池深度和打印部件的变形。温度、相对结晶度、应变、和压力进行评估。讨论了冷却速率对应变和应力演变的影响。