• 한국주조공학회지
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• 제25권3호
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• pp.128-133
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• 2005

The effects of Mn and Cr on the crystallization behaviors of Fe-bearing intennetallics in A356 alloy were studied. Coarse and acicular ${\beta}-Al_{5}$FeSi phase in A356-0.20wt.%Fe alloy was modified into small ${\alpha}$-Al(Fe,Mn)Si and ${\alpha}$-Al(Fe,Cr)Si phases in response to Mn and Cr addition, respectively. Increasing of Mn addition amount elevates the crystallizing temperature of ${\alpha}$-Al(Fe,Mn)Si and the Mn/Fe ratio in the ${\alpha}$-Al(Fe,Mn)Si. Cr is more effective to modify ${\beta}-Al_{5}$FeSi in comparison with Mn. ${\alpha}$-Al(Fe,Mn)Si phase had BCC/SC dual structure.

• 한국자기학회지
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• 제12권4호
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• pp.132-136
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• 2002

유리기관 위에 이온 빔 증착(ion beam deposition ; IBD)법으로 제작한 버퍼층(buffer layer) Si의 두께에 따른 ［NiFe/FeMn/NiFe］3층박막의 결정성과 교환결합세기(exchange bias field ; H$_{ex}$)를 조사하였다. 버퍼층 Si는 NiFe층을 fcc(111)로 매우 우세하게 초기에 결정성장 시켰다. Si/NiFe 위의 증착된 FeMn층은 ${\gamma}$-fcc(111)구조로 성장함에 따라 안정되고 큰 H$_{ex}$를 가졌고, 버퍼 110 Oe로 거의 일정하였으며, 상부 FeMn/NiFe 이중구조의 H$_{ex}$는 300 Oe까지 증가하였다. 버퍼층이 Ta일 경우와 비교해서 Si일 때 H$_{ex}$와 결정성이 향상되었다.이 향상되었다.

• 한국결정성장학회지
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• 제10권1호
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• pp.36-41
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• 2000

본 실험에서는 D.C magnetron sputtering을 사용하여 Ni-Fe/Co-Fe/Mn-Ir/Cu/buffer/Si 다층박막의 교환이방성에 관하여 연구하였다. 일반적인 Ni-Fe/Mn-Ir/buffer(Cu)/Si의 다층박막 구조는 낮은 교환결합 자계에 의하여 강자성체를 완전히 고착시키지 못한다. 따라서 Ni-Fe/Mn-Ir/buffer/Si 다층박막의 $H_{ex}$를 증가시키기 위해 하지층으로 Cu/Ta을 사용하여 Mn-Ir막의 결정립 부피를 증가시키고 Ni-Fe.Mn-Ir계면에 Co-Fe을 삽입하여 반강자성체/강자성체 계면에서의 epitaxy 경향을 향상시켜 2배 이상의 $H_{ex}$의 증가를 얻을 수 있었다. 또한 ferromagnete/Mn-Ir/buffer/Si의 다층박막 구조에서는 Mn-Ir거 두께에 따른 He일 변화 거동은 Mn-Ir/ferromagnete/buffer/Si다층박막구조와는 다른데 이와 같은 이유는 적층순서에 따라서 반강자성체 결정립의 부피분포와 계면에서의 교환결합 에너지가 차이가 나기 때문인 것으로 사료된다.

• 한국주조공학회지
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• 제33권6호
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• pp.233-241
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• 2013

Effect of Fe and Mn contents on the castability of Al-9wt%Si-xMg-yFe-zMn alloy has been studied. The alloy was composed of ${\alpha}$-Al phase, Al+eutectic Si phase, ${\beta}$-Al5FeSi compound and chinese script ${\alpha}$-$Al_{15}(Mn,Fe)_3Si_2$ compound. ${\beta}$-$Al_5FeSi$ and ${\alpha}$-$Al_{15}(Mn,Fe)_3Si_2$ compounds assumed to effect the fluidity and shrinkage behaviors of the alloy during solidification due to the crystallization of ${\alpha}$-$Al_{15}(Fe,Mn)_3Si_2$ and ${\beta}$-$Al_5FeSi$ compounds above eutectic temperature. As Fe and Mn contents of Al-9wt%Si-0.3wt%Mg system alloy increased from 0.15wt% to 0.6wt% and from 0.3wt% to 0.7wt%, fluidity of the alloy decreased by 5.7% and 3.3%, respectively. And as Mg content of Al-9wt%Si-0.45wt%Fe-0.5wt%Mn system alloy increased from 0.3wt% to 0.4wt%, fluidity of the alloy decreased by 8.6%. When Fe content of the alloy increased from 0.15wt% to 0.6wt%, macro shrinkage ratio decreased from 6.1% to 4.1%, and micro shrinkage ratio increased from 0.04% to 0.24%. Similarly, Mn content of the alloy increased from 0.3wt% to 0.7wt%, macro shrinkage ratio decreased from 6.0% to 4.5% and micro shrinkage ratio increased from 0.12% to 0.18%. Judging from the castability of the alloy, Al-9wt%Si-0.3wt%Mg alloy with low content of Fe and Mn, 0.1wt% Fe and 0.3wt% Mn, is recommendable.

• 한국주조공학회지
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• 제33권3호
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• pp.103-112
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• 2013

Effect of Fe and Mn contents on the tensile properties of Al-4 wt%Mg-0.9 wt%Si alloy system has been studied. Common phases of Al-4 wt%Mg-0.9 wt%Si alloy system were ${\alpha}$-Al, $Mg_2Si$, ${\alpha}-Al_{12}(Fe,Mn)_3Si$ and ${\beta}-Al_5FeSi$. As Fe content of Al-4 wt%Mg-0.9 wt%Si alloy system increased from 0.15 wt% to above 0.3 wt%, ${\beta}-Al_5FeSi$ compound appeared. When Mn content of the alloy increased from 0.3 wt% to 0.5 wt%, morphology of plate shaped ${\beta}-Al_5FeSi$ compound changed to chinese script ${\alpha}-Al_{12}(Fe,Mn)_3Si$. As Fe content of Al-4 wt%Mg-0.9 wt%Si-0.3 wt%Mn alloy increased from 0.15 wt% to 0.4 wt%, tensile strength of the as-cast alloy decreased from 191 MPa to 183 MPa and, elongation of the alloy also decreased from 8.0% to 6.2%. Decrease of these properties can be explained as the formation of plate shape, ${\beta}-Al_5FeSi$ phase with low Mn/Fe ratio of the alloy. However, when Mn content of Al-4 wt%Mg-0.9 wt%Si-0.3 wt%Fe alloy increased from 0.3 wt% to 0.5 wt%, tensile strength of as-cast alloy increased from 181 MPa to 194 MPa and, elongation of the alloy increased from 6.8% to 7.0%. These improvements attribute to the morphology change from ${\beta}-Al_5FeSi$ phase to chinese script, ${\alpha}-Al_{15}(Fe,Mn)_3Si_2$ phase shape-modified from with high Mn/Fe ratio of the alloy.

• 한국주조공학회지
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• 제33권2호
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• pp.55-62
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• 2013

Effect of Fe and Mn contents on the castability of Al-4wt%Mg-0.9wt%Si system alloy has been studied. According to the analysis of cooling curve for Al-4wt%Mg-0.9wt%Si-0.3wt%Fe-0.3/0.5wt%Mn alloy, ${\alpha}-Al_{15}(Fe,Mn)_3Si_2$ and ${\beta}-Al_5FeSi$ phases crystallized above eutectic temperature of $Mg_2Si$. Therefore, these phases affected both the fluidity and shrinkage behaviors of the alloy during solidification. As Fe and Mn contents of Al-4wt%Mg-0.9wt%Si system alloy increased from 0.1 wt% to 0.4 wt% and from 0.3 wt% to 0.5 wt% respectively, the fluidity of the alloy decreased by 26% and 33%. When Fe content of the alloy increased from 0.1 wt% to 0.4 wt%, 23% decrease of macro shrinkage and 19% increase of micro shrinkage appeared. Similarly, Mn content of the alloy increased from 0.3 wt% to 0.5 wt%, 11% decrease of macro shrinkage and 14% increase of micro shrinkage appeared. Judging from the castability of the alloy, Al-4wt%Mg-0.9wt%Si alloy with low content of Fe and Mn, 0.1 wt% Fe and 0.3 wt% Mn, is recommendable.

• 한국주조공학회지
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• 제31권1호
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• pp.18-25
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• 2011

Effect of Fe and Mn contents on the tensile properties has been studied in Al-9wt%Si-0.3wt%Mg alloy. As Fe content of Al-9wt%Si-0.3wt%Mg-0.5wt%Mn alloy increased from 0.15wt% to 0.45wt%, tensile strength of as-cast alloy decreased from 192 MPa to 174 MPa, and elongation of the alloy also decreased from 4.8% to 4.2%. Decrease of these properties can be explained as the formation of plate shape, ${\beta}-Al_5FeSi$ phase with high Fe/Mn ratio of the alloy. However when Mn content of Al-9wt%Si-0.3wt%Mg-0.45wt%Fe alloy increased from 0.3wt% to 0.5wt%, tensile strength of T6 aged alloy increased from 265 MPa to 275 MPa, and elongation of the alloy increased from 2.3% to 3.6%. These improvements attribute to chinese script, ${\alpha}-Al_{15}(Mn,Fe)_3Si_2$ phase shape-modified from ${\beta}-Al_5FeSi$ phase with low Fe/Mn ratio of the alloy.

• 상하수도학회지
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• 제27권5호
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• pp.631-639
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• 2013

국내 하수처리장 인 방류기준이 강화되어 다양한 방법의 인 제거기술이 적용되고 있다. 흡착은 비교적 간단하면서 효과적으로 인을 제거할 수 있다. 본 연구에서는 흡착제인 Fe-Mn-Si oxide와 Fe-Mn oxide을 개발하여, 인 제거효율을 검토하였으며 이 흡착제에 대하여 Kinetic과 Isotherm모델을 비교하였다. 두 흡착제의 최대흡착양은 각각 47.8, 35.5 mg-$PO{_4}^{3-}/g$이었고, 이들은 낮은 pH에서 효과적으로 흡착하였다. Freundlish isotherm 모델이 Langmuir 모델보다 Fe-Mn-Si oxide의 흡착에 더 적합했다. 이온성 용액은 인이 흡착되는 과정에서 음이온들과 경쟁관계로 흡착능이 감소되었다. 비록 음이온과 humic물질들로부터 흡착에 영향을 받지만 Fe-Mn-Si oxide는 Fe-Mn oxide보다 흡착능이 크게 나타났다.

• 한국분말재료학회지
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• 제15권5호
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• pp.345-351
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• 2008

The effects of the dopant (Mn) ratio on the microstructure and thermoelectric properties of $FeSi_2$ alloy were studied in this research. The alloy was fabricated by a combination process of ball milling and high pressure pressing. Structural behavior of the sintered bulks were systematically investigated by XRD, SEM, and optical microscopy. With increasing dopan (Mn) ratio, the density and ${\varepsilon}-FeSi$ phase of the sintered bulks increased and maximum density of 94% was obtained in the 0.07% Mn-doped alloy. The sintered bulks showed fine microstructure of ${\alpha}-Fe_{2}Si_{5}$, ${\varepsilon}-FeSi$ and ${\beta}-FeSi_2$ phase. The semiconducting phase of ${\beta}-FeSi_2$ was transformed from ${\alpha}-Fe_{2}Si_{5}+{\varepsilon}-FeSi$ phase by annealing.

• 한국주조공학회지
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• 제29권1호
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• pp.27-32
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• 2009

The microstructure of Al-7Si-0.4Mg-1Fe alloy mainly consists of aluminum dendrites, Al-Si eutectics, and $Al_5FeSi$ needles. When Mn was added to the alloy, the substantial amount of $Al_5FeSi$ phase was changed into Al(Mn,Fe)Si, however the needle-like morphology was almost unchanged. Combined additions of Cr or Sr with Mn to the base alloy resulted in rod-like Al(Mn, Fe,Si)Si phase. The tensile properties of as-cast alloys were enhanced by the Mn addition, especially when it was added with Sr. The tensile properties after T6 heat treatment was a little improved with 0.7%Mn addition, but Cr or Sr additions with Mn didn't show any positive effect on the properties of heat-treated alloys.