【摘 要】
：
Laser 3D printing based on melt growth has great potential in rapid preparation of Al2O3-based eutectic ceramics.In this work,large-scale Al2O3/GdAlO3/ZrO2 ternary eutectic ceramic rod with diameter of 4-5 mm and height higher than 250 mm was additively m
【机 构】
：
State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an,710072
论文部分内容阅读
Laser 3D printing based on melt growth has great potential in rapid preparation of Al2O3-based eutectic ceramics.In this work,large-scale Al2O3/GdAlO3/ZrO2 ternary eutectic ceramic rod with diameter of 4-5 mm and height higher than 250 mm was additively manufactured by laser directed energy deposition.Especially,heat treatment was applied to eliminate the microstructure heterogeneity in the as-deposited eutectic ceramic,and the microstructure homogenization mechanism was studied in depth.The results indicate that colonies and banded structures completely disappear after the heat treatment,producing a homogeneous network eutectic structure.The microstructure homogenization is revealed to experience three stages of discontinuous coarsening,continuous coarsening and microstructure coalescence.Addi-tionally,it is found that the eutectic spacing linearly increases with the heat treatment time,meaning that the coarsening behavior of the laser 3D-printed Al2O3/GdAlO3/ZrO2 eutectic ceramic satisfies well with the Graham-Kraft model.
其他文献
Incorporating antibacterial agent into biomimetic coating inspired by natural organisms with micro-nano structure surface has generated more interest for antifouling applications.In this work,poly(dimethylsiloxane)(PDMS)-based triblock copolymers and sub-
Ca3-x(PO4)2 ∶xTb3+(0.2≤x≤0.4),Ca2.3(PO4)2∶0.35Tb3+,0.35A+(A=Li,Na,K),and Ca2.3(PO4)2∶0.35Tb3+,yLi+(0.35≤y≤0.455)phosphors were prepared by solid-state reaction.All the prepared phosphors formed a rhombohedral unit cell with the R3c space group.To improve
The irreversible motion of magnetic domain walls in ferromagnets can dissipate a large portion of the elastic energy,and the associated damping capacity is proportional to the magnetostriction constant.In contrast,here we found that the damping capacity o
Three-dimensional(3D)graphene-based aerogels have significant potential for adsorption,sensors,and thermal management applications.However,their practical applications are limited by their disorganized structure and ultra-low resilience after compression.
Temperature-responsive resistance transition behaviors of the melamine sponges wrapped with different graphene oxide derivatives(i.e.nanoribbon,wide-ribbon and sheet)were investigated.Melamine sponge composites coated by three types of GO derivatives were
Heterogeneous Pd nanocatalysts are efficient catalysts for the Heck reaction but require multi-step,sophisticated procedures and harsh reaction conditions.In this work,a green and facile strategy has been developed to decorate Pd nanoparticles on polydopa
Tilt probe penetrating friction stir welding(PFSW)was an innovative technology proposed in recent years to avoid the formation of kissing bond in the root of joint.However,with the heat input decreasing,“S”line or zigzag line was easily introduced in the
This work investigates the strain rate dependence of dynamic recrystallization behaviour of high-purity zinc in room temperature compression under strain rates of 10-4 s-1,10-2 s-1 and 0.5 s-1.Results from electron backscatter diffraction provide insight
Aging treatment of Cu-based alloys is essential to enhance their strength that is desirable for their exten-sive engineering applications in electrical industry,whereas the underlying mechanism of strengthening is essential for massive manufacturing of th
A valid strategy to tailor the properties of polylactic acid for more extensive applications was introducing filler.In this work,basalt fiber assembled with in-situ SiO2 nanoparticles on the surface was successfully prepared via hydrothermal method and it