Structural large grains

Ferritic type. Welding produces a brittle deposit and a brittle heat-affected zone caused by the very large grain size that is produced. The problem may be reduced in severity by the use of austenitic fillers and/ or the application of pre- and post-weld heat treatments the latter is a serious limitation when large welded structures are involved. 

Une, K., Hirai, M., Nogita, K., Hosokawa, T., Suzawa, Y., Shimizu, S. Etoh, Y. 2000. Rim structure formation and high bumup fuel behavior of large-grained U02 fuels. Journal of Nuclear Materials, 278, 54-63. 

Understanding of vortex pinning mechanisms will steadily develop and with it the technology of optimising compositions and structures of materials for trapped field magnets, particularly the melt-textured, large grain varieties. 

ZnO films were deposited by RTF, MS, and PEMOCVD. In the case of RTF the ZnO films have a large-grained structure with no preferred crystallite orientation. On the contrary, ZnO films deposited by PFMOCVD and MS have fine-grained structure with an average grain-size of 40-60 nm. Under certain growth conditions ZnO films show a preferred orientation with the c-axis normal to the substrate. However, ZnO films prepared by... 

Lithium-Structure Compatibility. One of the critical chemistry problems of HYLIFE is the compatibility of structural alloys with the molten liquid of the jet array. Two candidate liquid metals are lithium and Pbg3Lij 7. High-Z metal (such as lead from target debris) will enter the liquid metal and may affect the compatibility. The structural alloy selected in the HYLIFE study is Cr-1 Mo, a ferritic steel. The carbides usually present in this steel are M3C (cementite) and M2C, where M is primarily Fe. Both of these carbides are unstable in lithium. M3C is usually present as platelets within pearlite, the eutectoid structure in pearlitic steel. The most common microstructure for the 2 4 Cr-1 Mo steel is large grains of ferrite with small islands of pearlite. M2C is present as a fine spray of precipitate within large ferrite grains. Lithium... 

The Cu deposition into and onto PS has been shown to take place by the immersion of PS in the solution CUSO4 + HF + H2O. It was shown for the first time that the PS subjected to the immersion into this solution demonstrated the following structure large well faceted Cu grains at the top, the porous finegrained Cu film underneath the large grains, and the Cu pointed rods extended from the surface into the PS layer. 

CSEM/SEI of broken lamellar eutectic micro structure for system H20-Na2S04. In between large grains ofprimary ice are eutectic colonies comprised of lamellar mirabilite grains in an ice-I matrix. The bulk composition of this sample is 4.0 wt%Na2S04, which corresponds to that of the eutectic. 

For the ferrite grades, it is necessary to have at least 12% chromium and only very small amounts of elements that stabilize austenite. For these materials, the structure is bcc from room temperature to the melting point. Some elements, such as Mo, Nb, Ti, and Al, which encourage the bcc structure, may also be in these steels. Because there are no phase transformations to refine the structure, britdeness from large grains is a drawback in these steels. They find considerable use in structures at high temperatures where the loads are small. 

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