摘要镍基高温合金不仅具有较好的高温强度、韧性、抗疲劳性能，还具有良好的抗氧化性和抗热腐蚀性能，广泛应用于航空、航天等领域。镍基合金中强化相的组织形态、尺寸、体积分数和空间的分布状况是影响该合金强化程度的主要因素。因此，研究镍铝高温合金中相的微观组织及其粗化规律对提高镍铝高温合金的各方面性能有着重要作用。 本文运用相场方法、周期性边界条件和半隐式傅里叶谱算法，在傅里叶空间中对Ginzburg-Landau方程和Cahn-Hilliard相场方程进行数值求解，利用Matlab7.0编程，研究了界面扩散下温度、浓度及弹性能对Ni-Al合金沉淀过程中相体积分数、平均粒径及其粗化行为的影响规律。 随着时效温度的降低，相体积分数增加、平均粒径增加、粗化速率增加；随着Al浓度的升高，相体积分数增加、平均粒径增加，粗化速率增加；在弹性能的作用下，相体积分数减小、平均粒径减小、粗化速率减小。 21595
毕业论文关键词 镍铝合金，沉淀相，相场方法，微观组织，粗化行为
Title The coarsening rule of Ni-Al alloy precipitation in the
interface diffusion
Abstract
Ni-based superalloy not only has good high temperature strength,
toughness, fatigue resistance performance, also has good corrosion
resistance to oxidation and thermal performance, widely used in aviation,
aerospace and other fields. Organization shape, size, volume fraction and
the space distribution of strengthen-phase in Ni-base superalloy are the
main factors influencing the degree of the alloy strengthening. So,
researching the high temperature Ni-Al alloy’s microstructure and its law
of phase-coarsening plays an important role in all respects to improve the
performance of Ni-Al superalloy.
In this paper, using the phase field method, periodic boundary conditions
and semi implicit Fourier spectrum algorithm, with Fourier space and Cahn
Hilliard the Ginzburg -Landau equation, make a solution for these. Using
phase field equation with Matlab7.0 programming, studied the interfacial
diffusion of temperature, concentration and elastic energy in the process
of Ni-Al alloy precipitation
-phase volume fraction, the influence of
the average particle size and its coarsening behavior patterns.
With the loss of the aging temperature, phase volume fraction, the average
particle size decreases and coarsening rate all decrease; With the increase
of Al concentration, phase volume fraction increases, the average particle
size increases, the coarsening rate increase. Under the action of elastic
energy, phase volume fraction, the average particle size decreases,
coarsening rate decrease.
Keywords Ni-Al alloy，precipitation，phase field method，Microstructure，
Coarsening behavior 目 次
1 绪论 1
1.1 研究背景及意义 1
1.2 计算机模拟研究 2
1.3 相场法组织模拟 . 2
1.4 镍铝二元合金及其强化机理 3
1.4.1 固溶强化机理 3
1.4.2 沉淀强化机理 4
1.4.3 粗化机理 4
1.5 本文研究内容 5
2 相场模型 7
2.1 相场模型理论基础 7
2.2 相场模型 8
2.3 Ni-Al合金相场模型的建立 10
2.3.1 相场控制方程 . 10
2.3.2 Ni-Al合金物性参数 13
2.3.3 数值模拟过程 . 14 Matlab界面扩散下 Ni-Al合金析出相粗化规律:http://www.751com.cn/cailiao/lunwen_13863.html