Following the experimental data in Part I of this article, the present paper considers existing strengthening mechanisms of dispersion-strengthened alloys, including Ansell–Lenel and Orowan–Ashby models, to explain yield strength increment after inserting incoherent and undeformable second-phase particles into a metal matrix. The influence of the particle type on the structure and flow stress under Ansell–Lenel model was evaluated using iron condensates, which contain the greatest number of combinations within the ‘matrix–neutral particle’ system. The shear modulus values for bulk materials are assumed to apply also to dispersed particles of the same composition when determining a yield strength increase. An increase in yield strength after inserting oxides, carbides, and borides into the metal matrix was inconsistent with the Ansell–Lenel model. In addition, Ansell defines a distance between particles using the volumetric approach to consider the second phase distribution within the matrix. According to the Orowan model modified by Ashby, the yield strength of the matrix with dispersed particles is calculated considering that a planar approach is used to define the distance between particles. This parameter is calculated as a mean value of the shortest distances between surfaces of neighboring particles in a sliding plane. It is shown that a distance between particles determined using a volumetric approach displays lower absolute values at the given volumetric content of the second phase compared to the planar approach. Consequently, the first approach (volumetric) suggests larger incremental values of the yield strength. In this study, a planar approach was also used as more realistic, for evaluating the distance between strengthening particles when estimating the yield strength increment following the Orowan–Ashby model. A model proposed in this work as a prototype of the Orowan analysis uses such parameters as a distance between dislocation clusters generated due to a blocking effect of the second phase and generation of dislocations by interface particle–matrix surface, taking into account a dispersed particle type and a size of an interface surface.

根据本文第一部分中的实验数据，本文考虑了弥散强化合金的现有强化机制，包括 Ansell-Lenel 和 Orowan-Ashby 模型，以解释在将非相干且不可变形的第二相粒子插入金属基体。Ansell-Lenel 模型下颗粒类型对结构和流动应力的影响使用铁凝聚物进行评估，铁凝聚物在“基质-中性颗粒”系统中包含最多的组合。在确定屈服强度增加时，假定散装材料的剪切模量值也适用于相同组成的分散颗粒。将氧化物、碳化物和硼化物插入金属基体后屈服强度的增加与 Ansell-Lenel 模型不一致。此外，Ansell 使用体积方法定义了粒子之间的距离，以考虑基质内的第二相分布。根据Ashby修改的Orowan模型，考虑使用平面方法定义颗粒之间的距离，计算具有分散颗粒的基体的屈服强度。该参数计算为滑动平面中相邻粒子表面之间最短距离的平均值。结果表明，与平面方法相比，使用体积方法确定的粒子之间的距离在第二相的给定体积含量下显示出较低的绝对值。因此，第一种方法（体积法）建议更大的屈服强度增量值。在这项研究中，平面方法也被用作更现实的，用于在根据 Orowan-Ashby 模型估算屈服强度增量时评估强化颗粒之间的距离。在这项工作中提出的模型作为 Orowan 分析的原型使用诸如由于第二相的阻塞效应而产生的位错簇之间的距离和界面粒子 - 基质表面产生的位错等参数，同时考虑了分散的粒子类型和界面的大小。