Microstructure characterization and mechanical properties of TiAl-based alloys prepared by mechanical milling and spark plasma sintering
Microstructure characterization and mechanical properties of TiAl-based alloys prepared by mechanical milling and spark plasma sintering
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机械铣削和放电等离子烧结制备TiAl基合金的显微组织表征和力学性能
DOI：
10.1016/j.matchar.2017.03.016
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发表时间：
2017-06
影响因子：
4.7
通讯作者：
Li Jianbo
中科院分区：
文献类型：
--
作者：
Wang Yan;Zhang Chi;Liu Yong;Zhao Shouxin;Li Jianbo
采用放电等离子烧结(SPS)技术对机械球磨和未球磨的高Nb TiAl合金粉末进行了致密化处理。研究了SPS温度和机械球磨处理对材料相组成和显微组织的影响，并测试了材料的室温力学性能。雾化粉末中的物相主要由α-2相、少量γ相和少量β相组成。球磨后α-2相的衍射峰明显展宽，γ相和β相的衍射峰强度均降低。雾化粉末和球磨粉末烧结的合金具有相似的相组成，包括大量的γ相和少量的α-2相。在1200℃的烧结温度下，用雾化粉末烧结的合金的显微组织由不均匀的γ和α2相以及少量的α2/γ片层团簇组成。相反，球磨粉末烧结的合金密度增加，显微组织明显细化。延长球磨时间或提高转速均可获得γ和α2均匀分布的致密合金。粉末在SPS过程中γ相的形核依赖于再结晶。变形的不均匀是雾化粉末烧结合金中形成非均匀γ晶的主要原因。γ相的不均匀形核和α-2颗粒的不均匀分布是造成原始粉末烧结合金晶粒度不均匀的主要原因。通过优化工艺参数，可以获得细晶细小、显微组织致密、力学性能好的合金。
High Nb containing TiAl alloy powders with or without mechanical milling were consolidated by spark plasma sintering (SPS) technique. The effects of SPS temperature and mechanical-milling treatment on phase constitution and microstructure were studied, and the mechanical properties at room temperature were tested. The phases in the as-atomized powder are composed of major α2phases, a few γ phases and a trace of β phases. After milling, the diffraction peaks for α2phase are obviously broadened, and the intensities of diffraction peaks for both γ phase and β phase are decreased. Similar phase constitution including a large quantity of γ phases and a few α2phases are exhibited in the alloys sintered by either as-atomized powder or as-milled powder. At a sintering temperature of 1200 °C, the microstructure of the alloy sintered by using as-atomized powder consists of inhomogeneous γ and α2phases as well as a few α2/γ lamellar colonies. By contrast, the densities increase and the microstructures are apparently refined for the alloys sintered by using as-milled powder. Fully dense alloys with uniformly distributed γ and α2grains can be obtained at extending milling time or increasing rotating speed. The nucleation of γ phase during SPS of the powders is dependent on recrystallization. The heterogeneity of deformation should be responsible for the formation of heterogeneous γ grains in the alloys sintered by using as-atomized powder. The heterogeneous grain size for the alloys sintered by using as-milled powders is mainly derived from the inhomogeneous nucleation of γ phase and the uneven distribution of α2grains. Good mechanical property accompanied by a fine grain size and a dense microstructure can be achieved by optimizing the process parameters.
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DOI：
10.1016/0921-5093(92)90050-b
发表时间：
1992-05
影响因子：
6.4
作者：
Y. Umakoshi;T. Nakano;T. Yamane
通讯作者：
Y. Umakoshi;T. Nakano;T. Yamane
影响因子：
6.2
作者：
H. Jabbar;A. Couret;L. Durand;J. Monchoux
通讯作者：
H. Jabbar;A. Couret;L. Durand;J. Monchoux
影响因子：
4.4
作者：
Yong-jiang Huang;Yu Wang;H. Fan;Jun Shen
通讯作者：
Yong-jiang Huang;Yu Wang;H. Fan;Jun Shen
影响因子：
9.4
作者：
S. Dey;A. Hazotte;E. Bouzy;Satoko Naka
通讯作者：
S. Dey;A. Hazotte;E. Bouzy;Satoko Naka
影响因子：
6
作者：
Hanliang Zhu;D. Seo;K. Maruyama;P. Au
通讯作者：
Hanliang Zhu;D. Seo;K. Maruyama;P. Au