<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0035-001X</journal-id>
<journal-title><![CDATA[Revista mexicana de física]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fis.]]></abbrev-journal-title>
<issn>0035-001X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0035-001X2018000200141</article-id>
<article-id pub-id-type="doi">10.31349/revmexfis.64.141</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Coercivity mechanism of rare-earth free MnBi hard magnetic alloys]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Zamora]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Betancourt]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Figueroa]]></surname>
<given-names><![CDATA[I.A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Investigaciones en Materiales Departamento de Materiales Metálicos y Cerámicos]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>04</month>
<year>2018</year>
</pub-date>
<volume>64</volume>
<numero>2</numero>
<fpage>141</fpage>
<lpage>144</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2018000200141&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2018000200141&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2018000200141&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract In this work, we present and discuss results concerning the hard magnetic behavior of rare earth-free MnBi alloys obtained by suction casting technique. The physics of coercivity for these type of alloys is based on the nucleation process of reverse domains, which in turn is determined by the alloy microstructure features such as phase distribution, morphology, grain size and in particular, defects, which are characteristic of real materials. The microstructure of the as-cast alloy presented here comprises the formation of the Low Temperature Intermetallic Phase (LTIP)-MnBi, interspersed within Biand Mn-rich areas. A considerable intrinsic coercivity field of 238 kA/m together with a saturation magnetization of 0.04 T were observed. The nucleation controlled mechanism of this alloy was described in terms of the Kronmüller equation, which incorporates the detrimental effect of microstructure defects through fitting parameters associated to reduced intrinsic magnetic properties at grain size boundaries, interfaces and local demagnetizing fields. A notorious switching of coercivity mechanism associated with domain wall pinning was found to be produced upon annealing of the alloy at 583 K for 24 hrs, yielding a drastic reduction of coercivity (down to 16 kA/m). The key microstructural feature determining the switching of coercivity mechanism is the formation/suppression of Bi-rich areas, which promotes the nucleation and growth of LTIP.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Magnetic materials]]></kwd>
<kwd lng="en"><![CDATA[hard magnetic properties]]></kwd>
<kwd lng="en"><![CDATA[coercivity]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Guo]]></surname>
<given-names><![CDATA[X]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[X]]></given-names>
</name>
<name>
<surname><![CDATA[Altounian]]></surname>
<given-names><![CDATA[Z]]></given-names>
</name>
<name>
<surname><![CDATA[Strom-Olsen]]></surname>
<given-names><![CDATA[J.O]]></given-names>
</name>
</person-group>
<source><![CDATA[Phys. Rev. B]]></source>
<year>1992</year>
<volume>46</volume>
<page-range>14578-82</page-range></nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
<name>
<surname><![CDATA[Sturius]]></surname>
<given-names><![CDATA[W.R]]></given-names>
</name>
</person-group>
<source><![CDATA[IEEE. Trans. Magn]]></source>
<year>1974</year>
<volume>10</volume>
<page-range>581-6</page-range></nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Williams]]></surname>
<given-names><![CDATA[H. J]]></given-names>
</name>
<name>
<surname><![CDATA[Sherwood]]></surname>
<given-names><![CDATA[R. C]]></given-names>
</name>
<name>
<surname><![CDATA[Booth]]></surname>
<given-names><![CDATA[O. L]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Appl. Phys]]></source>
<year>1957</year>
<volume>28</volume>
<page-range>445-7</page-range></nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Guo]]></surname>
<given-names><![CDATA[X]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[X]]></given-names>
</name>
<name>
<surname><![CDATA[Altounian]]></surname>
<given-names><![CDATA[Z]]></given-names>
</name>
<name>
<surname><![CDATA[Olsen]]></surname>
<given-names><![CDATA[J. O. S]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Appl. Phys]]></source>
<year>1993</year>
<volume>73</volume>
<page-range>6275-7</page-range></nlm-citation>
</ref>
<ref id="B5">
<label>5</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ping Liu]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Fullerton]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<name>
<surname><![CDATA[Gutfleishch]]></surname>
<given-names><![CDATA[O]]></given-names>
</name>
<name>
<surname><![CDATA[David]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<source><![CDATA[Sellmyer: Nanoscale Magnetic Materials and Applications]]></source>
<year>2009</year>
<edition>first</edition>
<page-range>476-9</page-range><publisher-loc><![CDATA[US ]]></publisher-loc>
<publisher-name><![CDATA[Springer]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B6">
<label>6</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Liu]]></surname>
<given-names><![CDATA[Yi]]></given-names>
</name>
<name>
<surname><![CDATA[Sellmyer]]></surname>
<given-names><![CDATA[D.J]]></given-names>
</name>
</person-group>
<source><![CDATA[Shindo: Handbook of Advanced Magnetic Materials]]></source>
<year>2006</year>
<edition>1</edition>
<page-range>8-31</page-range><publisher-loc><![CDATA[US ]]></publisher-loc>
<publisher-name><![CDATA[Springer]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B7">
<label>7</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Coey]]></surname>
<given-names><![CDATA[J. M. D]]></given-names>
</name>
</person-group>
<source><![CDATA[IEEE Trans. Magn]]></source>
<year>2011</year>
<volume>47</volume>
<page-range>4671-81</page-range></nlm-citation>
</ref>
<ref id="B8">
<label>8</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Okamoto]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
</person-group>
<source><![CDATA[Bi-Mn phase diagram. Alloy Phase Diagrams]]></source>
<year>1990</year>
<page-range>2/102</page-range><publisher-loc><![CDATA[OH ]]></publisher-loc>
<publisher-name><![CDATA[ASM International]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B9">
<label>9</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Andresen]]></surname>
<given-names><![CDATA[A. F]]></given-names>
</name>
</person-group>
<source><![CDATA[Acta.Chem Scand]]></source>
<year>1967</year>
<volume>21</volume>
<page-range>1543-54</page-range></nlm-citation>
</ref>
<ref id="B10">
<label>10</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Nithya]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Supercond. Nov. Magn]]></source>
<year>2013</year>
<volume>26</volume>
<page-range>3161-5</page-range></nlm-citation>
</ref>
<ref id="B11">
<label>11</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yin]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
<name>
<surname><![CDATA[Gu]]></surname>
<given-names><![CDATA[N]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Mater. Sci. Technol]]></source>
<year>1996</year>
<volume>12</volume>
<page-range>335-41</page-range></nlm-citation>
</ref>
<ref id="B12">
<label>12</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Koyama]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<name>
<surname><![CDATA[Onogi]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
<name>
<surname><![CDATA[Mitsui]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Nakamori]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Orim]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Watanabe]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
</person-group>
<source><![CDATA[Mater. Trans]]></source>
<year>2007</year>
<volume>48</volume>
<page-range>2414-8</page-range></nlm-citation>
</ref>
<ref id="B13">
<label>13</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kronmüller]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Fähnle]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<source><![CDATA[Micromagnetism and the microstructure of ferromagnetic solids]]></source>
<year>2003</year>
<publisher-loc><![CDATA[Cambridge ]]></publisher-loc>
<publisher-name><![CDATA[Cambridge University Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B14">
<label>14</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kronmüller]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Long]]></surname>
<given-names><![CDATA[G.J]]></given-names>
</name>
<name>
<surname><![CDATA[Grandjean]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
<name>
<surname><![CDATA[Kluwer]]></surname>
</name>
</person-group>
<source><![CDATA[Micromagnetic Background in Hard Magnetic Materials. In Supermagnets, Hard Magnetic Materials]]></source>
<year>1991</year>
<page-range>461</page-range><publisher-name><![CDATA[Dordrecht]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B15">
<label>15</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Skomski]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<name>
<surname><![CDATA[Coey]]></surname>
<given-names><![CDATA[J. M. D]]></given-names>
</name>
</person-group>
<source><![CDATA[Permanent Magnetism]]></source>
<year>1999</year>
<page-range>185</page-range><publisher-loc><![CDATA[London ]]></publisher-loc>
<publisher-name><![CDATA[Institute of Physics]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B16">
<label>16</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Saito]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
<name>
<surname><![CDATA[Nishimura]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<name>
<surname><![CDATA[Nishio-Hamane]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Magn. Magn. Mater]]></source>
<year>2014</year>
<volume>349</volume>
<page-range>9-14</page-range></nlm-citation>
</ref>
<ref id="B17">
<label>17</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zhang]]></surname>
<given-names><![CDATA[D. T]]></given-names>
</name>
<name>
<surname><![CDATA[Cao]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Yue]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Liu]]></surname>
<given-names><![CDATA[W.Q]]></given-names>
</name>
<name>
<surname><![CDATA[Zhang]]></surname>
<given-names><![CDATA[J.X]]></given-names>
</name>
<name>
<surname><![CDATA[Qiang]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Appl. Phys]]></source>
<year>2011</year>
<volume>109</volume>
</nlm-citation>
</ref>
<ref id="B18">
<label>18</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kavita]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Seelam]]></surname>
<given-names><![CDATA[U. M. R]]></given-names>
</name>
<name>
<surname><![CDATA[Prabhu]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Gopalan]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<source><![CDATA[J.Magn. Magn. Mater]]></source>
<year>2015</year>
<volume>377</volume>
<page-range>485-9</page-range></nlm-citation>
</ref>
<ref id="B19">
<label>19</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Basso]]></surname>
<given-names><![CDATA[V]]></given-names>
</name>
<name>
<surname><![CDATA[Olivetti]]></surname>
<given-names><![CDATA[E.S]]></given-names>
</name>
<name>
<surname><![CDATA[Martino]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
<name>
<surname><![CDATA[Küpferling]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<source><![CDATA[Int. J. Refrig]]></source>
<year>2014</year>
<volume>37</volume>
<page-range>266-72</page-range></nlm-citation>
</ref>
<ref id="B20">
<label>20</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yang]]></surname>
<given-names><![CDATA[J.B]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Phys.: Condens. Matter]]></source>
<year>2002</year>
<volume>14</volume>
<page-range>6509-19</page-range></nlm-citation>
</ref>
<ref id="B21">
<label>21</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ciszewski]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
<name>
<surname><![CDATA[Kozubowski]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Patejand]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
<name>
<surname><![CDATA[Sadowski]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<source><![CDATA[Memories Scientifique Rev. Metallurg]]></source>
<year>1972</year>
<volume>LXIX</volume>
</nlm-citation>
</ref>
<ref id="B22">
<label>22</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Unger]]></surname>
<given-names><![CDATA[W. K]]></given-names>
</name>
<name>
<surname><![CDATA[Slotz]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Appl. Phys]]></source>
<year>1971</year>
<volume>42</volume>
<page-range>1085-9</page-range></nlm-citation>
</ref>
<ref id="B23">
<label>23</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Barthem]]></surname>
<given-names><![CDATA[V.T.M.S]]></given-names>
</name>
</person-group>
<source><![CDATA[Physica B]]></source>
<year>2002</year>
<volume>319</volume>
</nlm-citation>
</ref>
<ref id="B24">
<label>24</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Curcio]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
</person-group>
<source><![CDATA[Physics Procedia]]></source>
<year>2015</year>
<volume>75</volume>
</nlm-citation>
</ref>
<ref id="B25">
<label>25</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kou]]></surname>
<given-names><![CDATA[X.C]]></given-names>
</name>
<name>
<surname><![CDATA[Kronmüller]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Givord]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Rossignol]]></surname>
<given-names><![CDATA[M.F]]></given-names>
</name>
</person-group>
<source><![CDATA[Phys Rev B]]></source>
<year>1994</year>
<volume>50</volume>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
