【摘 要】
：
As-cast microstructure of a designed polycrystalline Ni3Al-based superalloy is characterized using optical microscope,scanning electron microscope,transmission electron microscope equipped with selected area diffraction system,and the intermetallic phase
【机 构】
：
State Key Lab of Hydraulic Engineering Simulation and Safety, School of Materials Science and Engine
论文部分内容阅读
As-cast microstructure of a designed polycrystalline Ni3Al-based superalloy is characterized using optical microscope,scanning electron microscope,transmission electron microscope equipped with selected area diffraction system,and the intermetallic phase transformations involved during solidification process are determined based on thermal analysis measurements.The as-cast microstructure is mainly composed of 80.63 vol％ dendritic and 19.37 vol％ interdendritic phases,and the dendrite is identified as quasi-cuboidal γ\'Ⅰ phase connected by γ-channels where ultrafine γ\'Ⅱ particles are distributed,and the interdendritic phases are determined as γ\'-γ eutectic structure consisting of γE phase with dotted quasi-spherical γ\'Eparticles.During solidification,the dendrite firstly nucleates from liquid melt near 1348 ℃;subsequently,the residual liquidoid is transformed into interdendritic phases around 1326 ℃.Afterward,γ\'phase will precipitate from dendritic γmatrix with two-stage characteristics,resulting in the distinct precipitation of γ\'Ⅰ and γ\'Ⅱ phases when approaching to 1190 and 1043 ℃,respectively.The corresponding transformations involved during the solidification process can be translated as:Liquidoid｛Dendrite (γD) → γ\'I+γ (channel) →y\'Ⅰ+y\'Ⅱ+γ (channel)(80.63％)Residual liquidoid → Interdenrite(19.37 ％) (γ\'E-γE eutectic)｝As-cast
其他文献
The effect of sample geometry aspect ratio (l/w) on the giant magnetoimpedance (GMI) in Fe67Co18Si11B4 amorphous ribbons was investigated systematically.The GMI profiles were measured as a function of the external magnetic field at different frequencies u
A modified FGH96 superalloy using 0.1 wt％ graphene was successfully prepared using the wet mixing method.The interfacial bonding mechanism between the graphene and the superalloy matrix was characterized using optical microscope,scanning electronic micros
Dynamic and static aging precipitation of Mg17Al12 phases in AZ80 magnesium alloy was studied by multidirectional forging (MDF) with decreasing temperatures from 410 to 300 ℃ and subsequent aging process.The results show that the morphology of the β-Mg17A
A quantitative phase field method of multi-component diffusion-controlled phase transformations coupled with the Kim-Kim-Suzuki model was applied to study the effect of initial particle size distribution (PSD) in 3D and space distribution in 2D on dissolu
This research article explains the removal of methylene blue (MB) and malachite green (MG) from aqueous solution using adsorption/photodegradation activity of ZnO∶Ag/bamboo charcoal (BC) nanocomposite.In addition,the antibacterial studies of the prepared
The hot deformation behavior of S460ML steel with different Nb contents was investigated by single-pass compression experiment on the Gleeble-1500 thermo-machine simulator at deformation temperatures ranging from 900 to 1200 ℃ and strain rates from 0.1 to
An Ag2O/Ag electrode was prepared through the electrochemical oxidation of sterling silver.This electrode was used as a cathodic electron acceptor in a microbial fuel cell (MFC).The Ag2O/Ag electrode was characterized by scanning electron microscopy,X-ray
The relationship between the tensile properties and δ (delta) phase precipitation in cast alloy IN625 was investigated in this paper.Although the influences of δ phase on the mechanical properties have been pointed out in our previous work,the relationshi
Based on equiatomic nickel and titanium,three kinds of NiTiFe alloys with a nominal chemical composition of Ni49Ti49Fe2,Ni48Ti48Fe4 and Ni47Ti47Fe6 (at.％),respectively,have been designed to investigate the influence of the addition of Fe element on phase
Copper matrix composites were prepared through spark plasma sintering (SPS) process,mixing fixed amount of reduced graphene oxide (rGO) with the different amounts of Cr.In the sintered bulk composites,the layered rGO network and uniform Cr particles distr