Relation between undercooled solidification and solid-state grain growth accompanying dynamic segregation

Vacuum ◽  
2019 ◽  
Vol 161 ◽  
pp. 71-80 ◽  
Author(s):  
L.C. Feng ◽  
Z. Chen ◽  
Y. Fan ◽  
J.Y. Zhang ◽  
X.Q. Yang ◽  
...  
Keyword(s):  
Solid State ◽  
Grain Growth ◽  
Dynamic Segregation

Population balance model for solid state sintering II. Grain growth

2001 ◽  
Vol 27 (1) ◽  
pp. 63-71 ◽  
Author(s):  
S Sivakumar ◽  
Manjunath Subbanna ◽  
Satyam S Sahay ◽  
Vijay Ramakrishnan ◽  
P.C Kapur ◽  
...  
Keyword(s):  
Solid State ◽  
Grain Growth ◽  
Population Balance ◽  
Balance Model ◽  
Population Balance Model ◽  
Solid State Sintering

Microstructure Control and Structure Analysis in the Semi-Solid State of Different Feedstock Materials for the Bearing Steel 100Cr6

2006 ◽  
Vol 116-117 ◽  
pp. 177-180 ◽  
Author(s):  
Wolfgang Püttgen ◽  
Wolfgang Bleck ◽  
B. Hallstedt ◽  
Peter J. Uggowitzer
Keyword(s):  
Solid State ◽  
Grain Growth ◽  
Dynamic Mechanical Properties ◽  
Negative Influence ◽  
Bearing Steel ◽  
Cast Material ◽  
Fine Grained ◽  
Semi Solid ◽  
Hot Rolled ◽  
Feedstock Material

The bearing steel 100Cr6 in the forged and hardened condition is of great importance in industrial use. Escaping the geometry restrictions of conventional forging, the application of semi-solid metalworking (SSM) offers significantly increased design freedom. Using conventionally available rolled feedstock material with carbide banding, however, results in a higher segregation tendency during thixoforging, and thus special attention was paid to the feedstock’s “quality”. To achieve a fine-grained, globular microstructure in the semi-solid state, castings with and without the addition of 100 ppm titanium were compared with the hot rolled material. With its inherent nitrogen Ti forms TiN particles, which reduce grain-growth in austenite. The results indicate that TiN precipitates strongly affect grain growth during solid state processing, but the grain size in the semi-solid state can only be influenced for short process times. Generally the cast feedstock materials possess smaller globulites in the semi-solid state compared to forgings, so that a reduction of the sponge effect and a minimization of the segregation in produced components are expected. Since the cast material already showed a fine-grained, globulitic microstructure, the use of TiN is not recommended because of the possible negative influence of TiN on the dynamic mechanical properties.

scholarly journals Effect of Composition on the Growth of Single Crystals of (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 by Solid State Crystal Growth

Materials ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2357 ◽  
Author(s):  
Le ◽  
Fisher ◽  
Moon
Keyword(s):  
Growth Rate ◽  
Crystal Growth ◽  
Solid State ◽  
Single Crystal ◽  
Single Crystals ◽  
Grain Growth ◽  
Ceramic Powder ◽  
Single Crystal Growth ◽  
Crystal Growth Rate ◽  
Mixed Control

The (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 (NBT-100xST) system is a possible lead-free candidate for actuator applications because of its excellent strain vs. electric field behaviour. Use of single crystals instead of polycrystalline ceramics may lead to further improvement in piezoelectric properties but work on single crystal growth in this system is limited. In particular, the effect of composition on single crystal growth has yet to be studied. In this work, single crystals of (NBT-100xST) with x = 0.00, 0.05, 0.10 and 0.20 were grown using the method of Solid State Crystal Growth. [001]-oriented SrTiO3 single crystal seeds were embedded in (NBT-100xST) ceramic powder, which was then pressed to form pellets and sintered at 1200 °C for 5 min–50 h. Single crystal growth rate, matrix grain growth rate and sample microstructure were examined using scanning and transmission electron microscopy. The results indicate that the highest single crystal growth rate was obtained at x = 0.20. The mixed control theory of grain growth is used to explain the single crystal and matrix grain growth behaviour.

Monte-Carlo Simulation of Goss Abnormal Grain Growth in Fe-3%Si Steel by Sub-Boundary Enhanced Solid-State Wetting

2012 ◽  
Vol 715-716 ◽  
pp. 146-151
Author(s):  
K.J. Ko ◽  
A.D. Rollett ◽  
N.M. Hwang
Keyword(s):  
Monte Carlo ◽  
Solid State ◽  
Grain Boundary ◽  
Grain Growth ◽  
Boundary Energy ◽  
Three Dimensional ◽  
Abnormal Grain Growth ◽  
Grain Boundary Energy ◽  
Simulation Based ◽  
Mc Simulation

The selective abnormal grain growth (AGG) of Goss grains in Fe-3%Si steel was investigated using a parallel Monte-Carlo (MC) simulation based on the new concept of sub-boundary enhanced solid-state wetting. Goss grains with low angle sub-boundaries will induce solid-state wetting against matrix grains with a moderate variation in grain boundary energy. Three-dimensional MC simulations of microstructure evolution with textures and grain boundary distributions matched to experimental data is using in this study.

Graphoepitaxy of Ge on SiO2by solid‐state surface‐energy‐driven grain growth

1984 ◽  
Vol 45 (6) ◽  
pp. 631-633 ◽  
Author(s):  
T. Yonehara ◽  
Henry I. Smith ◽  
C. V. Thompson ◽  
J. E. Palmer
Keyword(s):  
Solid State ◽  
Surface Energy ◽  
Grain Growth

Effects of CuO on the Preparation, Microstructure and Dielectric Response of CaCu3Ti4O12

2008 ◽  
Vol 368-372 ◽  
pp. 121-122
Author(s):  
Jian Fang Qiao ◽  
Dan Dan Qin ◽  
Li Guan ◽  
Hai Long Wang ◽  
Rui Zhang
Keyword(s):  
Solid State ◽  
Grain Growth ◽  
Barrier Layer ◽  
Solid State Reaction ◽  
Dielectric Response ◽  
Second Step ◽  
Sintering Process ◽  
Ceramic Capacitor ◽  
Inhomogeneous Microstructure ◽  
Maximum Permittivity

CaCu3Ti4O12 (CCTO) barrier layer ceramic capacitor was prepared by a two-step sintering process. The CCTO powders were pre-synthesized at 900oC by solid-state reaction and the effects of the amount of CuO on the formation of the CCTO powders were investigated. The CCTO ceramics were prepared by the second-step sintering. It was found that the abnormal grain growth and inhomogeneous microstructure are controlled by the amount of excessive CuO. The optimized CuO content in the composites is ~14 wt%. The maximum permittivity is 115,000 (1 kHz, 210oC).

New Understanding of Abnormal Grain Growth Approached by Solid-State Wetting along Grain Boundary or Triple Junction

2004 ◽  
Vol 467-470 ◽  
pp. 745-750 ◽  
Author(s):  
Nong Moon Hwang
Keyword(s):  
Solid State ◽  
Grain Boundary ◽  
Grain Growth ◽  
Triple Junction ◽  
Boundary Energy ◽  
Growth Front ◽  
Abnormal Grain Growth ◽  
Boundary Mobility ◽  
Grain Boundary Mobility ◽  
Mc Simulation

Although it has been generally believed that the advantage of the grain boundary mobility induces abnormal grain growth (AGG), it is suggested that the advantage of the low grain boundary energy, which favors the growth by solid-state wetting, induces AGG. Analyses based on Monte Carlo (MC) simulation show that the approach by solid-state wetting could explain AGG much better than that by grain boundary mobility. AGG by solid-state wetting is supported not only by MC simulations but also by the experimental observation of microstructure evolution near or at the growth front of abnormally growing grain. The microstructure shows island grains and solid-state wetting along grain boundary and triple junction.

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