Driving force evolution in solid-state sintering with coupling multiphysical fields
Driving force evolution in solid-state sintering with coupling multiphysical fields
复制标题
多物理场耦合固态烧结驱动力演化
DOI：
10.1016/j.ceramint.2020.01.187
复制
发表时间：
2020-06-01
影响因子：
5.2
通讯作者：
Wu Zhouzhi
中科院分区：
文献类型：
--
作者：
Tan Shulin;Zhang Xiaomin;Wu Zhouzhi
提出了一种基于热-力-扩散耦合方程的相场模型，用于模拟热压烧结非等温条件下的组织演变。不同升温速率下的模拟结果与实验致密化曲线基本一致。进一步的研究表明，温度梯度驱动力随加热速率的增加而增大，而在不同的加热速率下，相同形状(对应于一定的相对颈部半径)的浓度梯度驱动力和应变梯度驱动力是相同的。模拟结果表明，在理想的两球等半径模型中，浓度梯度驱动力随颈长的演化趋势与用Fick定律推导的经典理论一致。最后，在恒温假设下，得到了烧结驱动力和颈长生长速率的动力学方程，并证明了颈长生长动力学方程在不同相场参数和不同烧结温度下的有效性。
A phase field model based on coupled thermo-mechano-diffusional equations is presented to simulate the microstructure evolution of hot pressing sintering under nonisothermal conditions. Simulation results for different heating rates are basically consistent with the experimental densification curves. Further research shows that the temperature gradient driving force increases with the heating rates, whereas the driving force of concentration and strain gradients are the identical in the same shape (corresponding to a certain relative neck radius) with different heating rate. Moreover, Simulation results indicate the evolution trend of the concentration gradient driving force along with neck growth is consistent with that from the classical theory which derived using Fick's law in an ideal two-sphere equal-radius model. Finally, a dynamic equations of sintering driving force and neck growth rate are obtained under the assumption of constant temperature, and the dynamic equation of neck growth was proved to be valid in different phase field parameters and sintering temperatures.