In isotropic pressure-less sintering continuum mechanics models, densification kinetics is driven by the balance between the effective sintering stress and bulk viscosity. In components manufactured by binder jetting (BJ), the green structure created by the arrangement of spherical powder particles during printing is characterized by its high porosity (40–50%). This leads to a wide porosity range for the initial and intermediate sintering stages, where a complex combination of diffusion mechanisms drives matter redistribution through the porous compact. In this paper, a comprehensive analysis of the porosity effect on the resistance to densification of 316L BJ during sintering was performed by avoiding other highly influencing factors like δ-ferrite phase transformation. Different normalized bulk moduli expressions, inspired by Skorohod, Hsueh, and Abouaf sintering models, are used in the framework of the continuum theory of sintering. A new material constants determination algorithm based on the sintering experiments design and non-linear analysis of the model was proposed. This evidenced the critical importance of the experimental data collection for the determination of the required sintering model constants. Accordingly, material shear viscosity and normalized bulk viscosity constants were successfully determined based on dilatometry and grain size experimental data. The bulk moduli proposed comprise physical parameters which depend on the interparticle stress distribution or the initial high reactivity of the BJ compacts. The variation of powder size distribution and/or arrangement would potentially impact the determination of these constants in the normalized bulk moduli.

在各向同性无压烧结连续体力学模型中，致密化动力学由有效烧结应力和体积粘度之间的平衡驱动。在通过粘合剂喷射 (BJ) 制造的部件中，印刷过程中球形粉末颗粒排列形成的生坯结构具有高孔隙率 (40–50%) 的特点。这导致初始和中间烧结阶段的孔隙率范围很宽，其中扩散机制的复杂组合驱动物质通过多孔压块重新分布。在本文中，通过避免 δ-铁素体相变等其他高度影响因素，综合分析了孔隙率对 316L BJ 烧结过程中抗致密化的影响。不同的归一化体积模量表达式，灵感来自 Skorohod、Hsueh、和 Abouaf 烧结模型，用于烧结连续介质理论的框架中。提出了一种基于烧结实验设计和模型非线性分析的新材料常数确定算法。这证明了实验数据收集对于确定所需烧结模型常数的重要性。因此，基于膨胀测定法和晶粒尺寸实验数据成功确定了材料剪切粘度和归一化体积粘度常数。所提出的体积模量包括取决于颗粒间应力分布或 BJ 压块的初始高反应性的物理参数。粉末尺寸分布和/或排列的变化可能会影响归一化体积模量中这些常数的确定。