Inclusions modification by rare earth in steel and the …
Rare earth (RE) elements are excellent modifiers for non-metallic inclusions that inevitably appear in steel and affect steel properties. This paper reviews the research status of inclusions modification by RE elements and the changes it cause on steel properties. First, the inclusion changes caused by RE modification are described.
The effect of rare earth dopants on grain boundary
The effect of rare earth (RE) grain boundary segregation on mode of fracture in alumina has been investigated. In order to isolate the effects of microstructure (i.e. grain size and residual porosity) from those due to grain boundary chemistry, the fracture behaviour of virtually pore-free (i.e. nearly transparent) undoped alumina has …
Inclusions modification by rare earth in steel and the …
Contrary to the results obtained by Zhou et al., 66 Cheng et al., 67 and Luo et al., 68 an evolution route resulting in the final production of Ce–O and Ce–O–S was reported, of which the morphology and elemental mapping of inclusions are shown in Fig. 2. 71 For example, Huang et al. 72 added Ce to H13 steel and found that Ce could …
Segregation‐controlled densification and grain …
Segregation-controlled densification and grain growth in rare earth-doped Y 2 O 3. Moritz Kindelmann, Ke Ran, Wolfgang Rheinheimer, Koji Morita, Joachim Mayer, Martin Bram, Olivier Guillon. First published: …
Modifying Tb-Cu grain boundary diffusion behavior in Nd
The grain boundary diffusion using mixed rare earths (REs) as the diffusion source is very effective in enhancing the coercivity of Nd-Fe-B magnets. Here, we firstly investigated the Gd added Tb-Cu diffusion alloys and found that the coercivity of Nd-Fe-B magnets can be improved from 1094 kA/m to 1704, 1677 and 1593 kA/m by Tb 70 Cu 30 …
Effect of Annealing Parameters on Microstructure and Rare Earth …
During the period, the transition from low-angle grain boundaries to high-angle grain boundaries within the deformed grains and the encroachment of recrystallized grains on the deformed grains were the main recrystallization mechanisms, dislocations were consumed, and the residual stresses were reduced. ... a rare earth (RE) texture …
Rare-earth element partitioning between sphene and
Over 80 sets of partition coefficients (D) for 4 rare-earth elements (REE) (La, Sm, Ho, Lu) partitioning between sphene and coexisting silicate liquid at 7.5 to 30 kbar and 900° to 1120°C, demonstrate that D-values increase with: (a) increasing SiO 2 content of the coexisting liquid; (b) increasing pressure; and (c) decreasing …
These 13 Ancient Grains of the World May Hold the Key to …
An Ethiopian ancient grain, Teff is said to be the tiniest grain on earth; it is 150 times smaller than a single wheat kernel. When ground into a flour, it's used to make the Ethiopian staple injera, a spongy fermented flatbread. ... forbidden rice or chak hao is a rare and nutritious grain offering the many health benefits found in ...
Grain Boundary Strengthening in Alumina by Rare …
Several simple models to explain the increase in GB creep resistance due to rare earth impurity doping have been proposed (4, 5), but the atomic-scale mechanism of how these dopants actually strengthen …
Thermal Analysis of Rare Earth Grain Refined 4130
This paper discusses the thermal analysis of rare earth grain refined 4130. To accomplish this, heats of 4130 Baseline, 0.3 wt% RE silicide, and 0.3 wt% EGR were poured in a thermal analysis cup with a single S-type thermocouple at the bottom. A data acquisition system recorded the cooling curves whose values were compared to …
Exploring the mechanism of "Rare Earth" texture …
The effect of rare earth element segregation on grain boundary energy and mobility in magnesium and ensuing texture …
Grain Size Distribution and Clay Mineral Distinction …
The results showed that the grain size and volume curve of rare earth ore have unimodal and bimodal shapes, respectively. X-ray diffraction showed the …
Properties improvement and structural optimization of
Non-rare earth compound (MgO) is employed for NdFeB grain boundary diffusion. • Improvements of the magnetic properties and corrosion resistance are obtained. • MgO can modify the composition and structure of the grain boundary phase. • This process has great significance in minimizing the use of rare earth.
Thermal Analysis of Rare Earth Grain Refined 4130
This paper discusses the thermal analysis of rare earth grain refined 4130. To accomplish this, heats of 4130 Baseline, 0.3 wt% RE silicide, and 0.3 wt% EGR were poured in a thermal analysis cup with a single S-type thermocouple at the bottom. A data acquisition system recorded the cooling curves whose values were compared to reference data.
Effect of Rare Earth Additions on Grain Refinement of
Rare earth element cerium is an efficient grain refiner. In this paper, four different cerium contents are added to 18-carat Au–Ag–Cu–Zn alloys. The microstructures of these kinds of as-cast ...
Effect of Rare Earth on the Carbide in Steel | SpringerLink
The addition of rare earth to high manganese austenitic steel can refine the grains and make the carbides distributed uniformly, improving the strength and plastic toughness of high manganese steel [].Adding rare earth in tool steel D2 can refining the as cast microstructure and provide heterogeneous nucleation core for the formation of …
Grain-size effect on rare earth elements in Pahang River and …
Grain size is an important controlling factor of the chemical composition of sediments. To understand the role of grain size in the content of rare earth elements (REE) in tropical mountainous river sediments and to establish suitable provenance proxies, sediments collected from Pahang River and Kelantan River, Peninsular Malaysia, were …
Strengthening of low-cost rare earth magnesium alloy Mg …
The grain size is significantly refined, reaching 1.14 μm. (1) The strength enhancement of the low-cost rare-earth magnesium alloys after MDF is related to solid solution strengthening and more attributed to the combined effect of the grain refinement and aging precipitates. (2)
Effects of Rare Earth Dopants on Grain Boundary Bonding in …
The segregation effects of the rare-earth dopants at grain boundaries are also known in the literature for different ceramic compounds, e.g. for Al 2 O 3 -SiC doped with Y 3+, Nd 3+ or La 3+ [14
Effects of rare earth elements addition on …
Results show that rare earth elements can refine grains, improve hardness, tensile strength, and impact absorption energy of GCr15 bearing steel under different heat treatment conditions. Besides, it has been found that rare earth elements are beneficial …
The role of anti-core–shell structure caused by over …
Grain boundary diffusion (GBD) process is an effective method to fabricate high-coercive Nd-Fe-B magnets with less consumption of heavy rare earth (HRE). By this approach, HRE-rich shell forms around the Nd2Fe14B grain, which can hinder the magnetic reversal starting at the edge of the grains and enhance the coercivity of whole magnet. …
Toward deformability enhancement of rare earth …
After the plastic deformation of rare earth magnesium alloys, the grain size was refined obviously and the stress inside the materials is larger. Therefore, the grain boundary is very blurred under OM, so the Electron Backscattered Diffraction (EBSD, Nordly Max 3) as a powerful tool for grain orientation, size distribution, boundary …
Enhancing coercivity and mechanical strength of
1. Introduction. Nd-Fe-B permanent magnets have been widely used in the field of renewable energy applications with high working temperatures [1].Since the Nd 2 Fe 14 B main phase (2:14:1 phase) exhibits a rapid decrease in anisotropy field (H A) with increasing temperature and low Curie temperature [2], heavy rare earth (HRE) elements …
Grain Boundary Segregation of Rare-Earth Elements …
A simple classical model has been applied to predict the solute drag effect associated with the rare-earth (RE) segregation to grain boundaries. It is demonstrated …
Recent advances on grain refinement of magnesium rare-earth …
High-performance cast magnesium rare-earth (Mg-RE) alloys are one of the most important materials among all developed Mg alloy families, and have shown great potential in military and weapons, aerospace and aviation, orthopedic implants, etc. Controlling grain size and distribution of it is key to the promising mechanical …
The electronic origins of the "rare earth" texture …
The effect of rare earth element segregation on grain boundary energy and mobility in magnesium and ensuing texture weakening. Scripta Mater. 146, 46–50 …
Development of non-rare earth grain boundary
This review summarizes the development of grain boundary modification techniques with emphasis on our recent work using cost-effective non-rare earth (non-RE) sources for GBD. Up to now, heavy rare earth (HRE) based compounds, metals and light rare earth (LRE) based alloys have been successfully employed as the diffusion sources …
Microstructure and performance of rare earth …
Alloying elements such as Re, Hf, Zr, and Nb help modify impurity distributions and effectively strengthen the grain boundaries of W 13. In addition, rare-earth (RE) elements such as La and Y show ...
A LA-ICP-MS analysis of rare earth elements on phosphatic grains …
Request PDF | A LA-ICP-MS analysis of rare earth elements on phosphatic grains of the Ediacaran Doushantuo phosphorite at Weng'an, South China: implication for depositional conditions and ...
Phase Stability of Nanocrystalline Grains of Rare-Earth …
Rare-earth (RE) oxides are important in myriad fields, including metallurgy, catalysis, and ceramics. However, the phase diagram of RE oxides in the nanoscale might differ from the phase diagrams for bulk, thus attracting attention nowadays. We suggest that grain size in the nanoscale also determine …
