Processing behavior of nanocrystalline NiAl during milling, sintering and mechanical loading and interpretation of its intergranular fracture

作者：Rahaei Mohammad Bagher^*; Jia Dechang

来源：Engineering Fracture Mechanics, 2014, 132: 136-146.

DOI：10.1016/j.engfracmech.2014.10.022

• Nanocrystalline NiAl
• Sintering
• Mechanical properties
• Microstructure
• Dislocation
• Intergranular fracture

Processing behavior of Ni and Al powders during milling, sintering and compression loading was evaluated using SEM, TEM and XRD-Rietveld's refinement analysis techniques. Nanocrystalline NiAl intermetallic along with microstrain and dislocations on its microstructure was obtained after milling. Sintering of nanocrystalline powders at 1180 degrees C under a pressure of 48 MPa for 1 h time by hot press technique resulted in grain growths toward ultrafine along with decreasing of microstrain and dislocations on microstructure. Obtaining a microstructure of ultrafine grained NiAl resulted in improvement of mechanical properties. Intergranular fracture was characterized by the coupling of dislocations at grain boundaries that caused to formation of voids/cracks with progressive loading.

• 出版日期2014-12
• 单位哈尔滨工业大学