Excellent strength-ductility synergy of NiAl-based composites achieved by a 3-dimensional network structure. (15th January 2022)

• Record Type: Journal Article
• Authors: Lu, Zhen; Liu, Dekai; Shi, Chengcheng; Xiao, Han; Liu, Wei; Jiang, Shaosong
• Is Part Of: Composites. Number 229(2022)
• Publication Date: 2022-01-15
• Subjects: NiAl-based composites -- 3-Dimensional network structure -- Strength-ductility synergy -- Strengthening and toughening mechanisms; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2021.109457
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: NiAl intermetallic compounds have attracted the attention of researchers in the field of high-temperature structural materials, but their poor room-temperature ductility and insufficient high-temperature strength crying out for solutions have hindered their practical application. To solve these problems, a novel 3-dimensional network structure-reinforced NiAl-based composite was designed by hot presing sintering sinter with pre-alloyed powders. The 3-dimensional network structure was composed of discrete nearly spherical HfO2 and rod-shaped HfRe2 . The mechanical properties of the composites were closely correlated with the distribution of the 3-dimensional network structure in the matrix, which was controlled by the sintering temperature and holding time. A microstructure with a desirable 3-dimensional network structure distribution and the best comprehensive mechanical properties was produced at 1375 °C/60 min. The microstructural evolution along with the strengthening and toughening mechanisms were discussed in detail. The increase in the high-temperature strength was mainly attributed to the pinning effect of the 3-dimensional network structure on dislocations and the restraining effect on the sliding and rotation between the matrix grains, while the increase in room-temperature ductility was mainly due to the grain refinement and hindering of crack propagation by the 3-dimensional network structure. In this paper, the development of a novel low-density NiAl-based composite with a 3-dimensional network structure improved both the strength and ductility, providing design ideas for the application of NiAl-based materials.