Effects of magnetic field heat treatment on Sm–Co/α-Fe nanocomposite permanent magnetic materials prepared by high energy ball milling

Room temperature, high energy ball milling was applied to various transition aluminas (γ, K, χ), producing thermodynamically stable α-alumina–a phenomenon that could otherwise be achieved only by high temperature (1100–1200 °C) heat treatment. The transformation proceeds in two steps. The first one consists of rapid microstructural rearrangements with continuously increasing α-transformation rate. In the second step (1–2 h from the start), only relatively small changes in morphology are observed with a constant α-transformation rate. The rate is influenced only by the milling intensity. The presence or the absence of oxygen in the milling atmosphere has a large influence on the final surface area of α-alumina.

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Formation of TiB2/TiN/Ti (CxN1−x) nanocomposite powder via high-energy ball milling and subsequent heat treatment

Journal of Alloys and Compounds ◽

10.1016/s0925-8388(01)01769-8 ◽

2002 ◽

Vol 334 (1-2) ◽

pp. 253-260 ◽

Cited By ~ 33

Author(s):

Jianlin Li ◽

Fei Li ◽

Keao Hu ◽

Yong Zhou

Keyword(s):

Heat Treatment ◽

Ball Milling ◽

High Energy ◽

High Energy Ball Milling ◽

Subsequent Heat Treatment ◽

Nanocomposite Powder ◽

Energy Ball

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Preparation of Ti+Ti6Si2B+Ti5Si3 and Ti+Ti6Si2B+TiB Powders by High-Energy Ball Milling and Subsequent Heat Treatment

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.24-25.467 ◽

2005 ◽

Vol 24-25 ◽

pp. 467-470 ◽

Cited By ~ 3

Author(s):

Bruno Bacci Fernandes ◽

Alfeu Saraiva Ramos ◽

Paulo Atsushi Suzuki

Keyword(s):

Heat Treatment ◽

Ball Milling ◽

High Energy ◽

High Energy Ball Milling ◽

Subsequent Heat Treatment ◽

Energy Ball

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High-Energy Ball Milling and Subsequent Heat Treatment of Ti-Cu-Si-B Powders

Materials Science Forum ◽

10.4028/www.scientific.net/msf.899.463 ◽

2017 ◽

Vol 899 ◽

pp. 463-468

Author(s):

Lucas Moreira Ferreira ◽

Bruno Bacci Fernandes ◽

Mario Ueda ◽

Alfeu Saraiva Ramos

Keyword(s):

Heat Treatment ◽

Ball Milling ◽

High Energy ◽

Phase Region ◽

High Energy Ball Milling ◽

Subsequent Heat Treatment ◽

Limited Information ◽

Heat Treated ◽

Structural Applications ◽

Energy Ball

Metal matrix multicomponent alloys and others based on the Ti+Ti6Si2B phases are potentially attractive for structural applications. However, there is limited information in literature on the effect of alloying in stability of the Ti6Si2B compound, which presents its single-phase region close to Ti-22Si-11B alloy composition (at.-%). In this sense, this work discusses on the effect of copper addition on the stability of the Ti6Si2B compound. Elemental powder mixtures were used to prepare the Ti-xCu-22Si-11B (x=2 and 6 at.-%) alloys by high-energy ball milling and subsequent heat treatment (1100oC for 240 minutes). The as-milled Ti-Cu-Si-B powders and heat-treated samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). Similar behavior was noted during ball milling of Ti-Cu-Si-B powders, i.e., the Ti5Si3 phase was formed after milling for 180 minutes. The mechanically alloyed and heat treated Ti-2Cu-22Si-11B alloy presented a matrix of Ti6Si2B dissolving close to 2 at.-% Cu. Precipitates of Ti5Si3 and other unknown Cu-and Fe-rich phase were also identified in microstructures of these quaternary alloys, whose amounts were increased in the mechanical alloyed and heat treated Ti-6Cu-22Si-11B alloy.

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