Posco Co., Ltd

Posco

Lg Display Co., Ltd.

Postech Academy-Industry Foundation

Snu Rdb Foundation

Call Gate Co., Ltd.

Yong-Jin Kim

Sung-Kyu Kim

Un-Hae Lee

Sang-Deok Kang

Soon-Gi Lee

Hong-Yeol Oh

Hak-Cheol Lee

In-Gyu Park

In-Shik Suh

Hong-Ju Lee

Gyu-Chul Yi

Young-Deok Jung

Seung-Yong Lee

Chul-Ho Lee

Cheol-hun Jang

Yu-Mi Ha

Yoen-Jung Park

Il-Cheol Yi

Young-Joon Hong

Tae-Kyo Han

Jin-Kyoung Yoo

Young-Ju Kim

Provided according to one embodiment of the present invention are a non-magnetic steel material and a method for manufacturing the same. The steel material comprises 15-27 wt % of manganese, 0.1-1.1 wt % of carbon, 0.05-0.50 wt % of silicon, 0.03 wt % or less (0% exclusive) of phosphorus, 0.01 wt % or less (0% exclusive) of sulfur, 0.050 wt % or less (0% exclusive) of aluminum, 5 wt % or less (0% inclusive) of chromium, 0.01 wt % or less (0% inclusive) of boron, 0.1 wt % or less (0% exclusive) of nitrogen, and a balance amount of Fe and inevitable impurities, has an index of sensitivity of 3.4 or less, the index of sensitivity being represented by the following relational expression (1): [Relational expression 1]−0.451+34.131*P+111.152*Al−799.483*B+0.526*Cr≤3.4 (wherein [P], [Al], [B] and [Cr] each mean a wt % of corresponding elements), and contains a microstructure with austenite at an area fraction of 95% or greater therein.

Austenitic steel material having excellent hot workability and manufacturing method therefor

A high-strength austenite-based high-manganese steel material and a manufacturing method for the same, the steel material comprising: manganese (Mn): 20 to 23 wt %, carbon (C): 0.3 to 0.5 wt %, silicon (Si): 0.05 to 0.50 wt %, phosphorus (P): 0.03 wt % or less, sulfur (S): 0.005 wt % or less, aluminum (Al): 0.050 wt % or less, chromium (Cr): 2.5 wt % or less, boron (B): 0.0005 to 0.01 wt %, nitrogen (N): 0.03 wt % or less, and a balance of iron (Fe) and other inevitable impurities, wherein stacked defect energy (SFE) represented by the following relationship 1 is 3.05 mJ/mor more, and a microstructure comprises 95 area % or more (including 100 area %) of austenite, and comprises 6 area % or more of strain grain boundaries in an austenite recrystallized grain, is provided.SFE(mJ/m)=&#x2212;24.2+0.950*Mn+39.0*C&#x2212;2.53*Si&#x2212;5.50*Al&#x2212;0.765*Cr&#x2003;&#x2003;[Relationship 1]where Mn, C, Cr, Si, and Al denote weight percent of respective components.

High-strength austenite-based high-manganese steel material and manufacturing method for same

The present invention relates to a high manganese steel for low temperature applications and a method for manufacturing the same. The high manganese steel contains 0.3 wt % to 0.8 wt % of C, 18 wt % to 26 wt % of Mn, 0.01 wt % to 1 wt % of Si, 0.01 wt % to 0.5 wt % of Al, 0.1 wt % or less of Ti (excluding 0%), 1 wt % to 4.5 wt % of Cr, 0.1 wt % to 0.9 wt % of Cu, 0.03 wt % or less of S (excluding 0%), 0.3 wt % or less of P (excluding 0%), 0.001 wt % to 0.03 wt % of N, 0.004 wt % or less of B (excluding 0%), and a remainder of Fe and other inevitable impurities, wherein a microstructure comprises an austenite single phase structure, and an average grain size of the austenite is 50 &#x3bc;m or less.

High manganese steel for low temperature applications having excellent surface quality and a manufacturing method thereof

Provided according to one preferred aspect of the present invention are austenitic steel material having superb abrasion resistance and toughness, and a method for producing the austenite steel material. The austenitic steel material having superb abrasion resistance and toughness according to one preferred aspect of the present invention comprises, in wt %, 0.6-1.9% carbon (C); 12-22% manganese (Mn); 5% or lower (excluding 0%) chromium (Cr); 5% or lower (excluding 0%) copper (Cu); 0.5% or lower (excluding 0%) aluminum (Al); 1.0% or lower (excluding 0%) silicon (Si); 0.1% or lower (including 0%) phosphorous (P); 0.02% or lower (including 0%) sulfur (S); and the rest in Fe and unavoidable impurities, and has the microstructure comprising, by surface area fraction, 97% or higher (including 100%) austenite and 3% or lower (including 0%) carbide.

Austenitic steel material having excellent abrasion resistance and toughness and manufacturing method the same

Provided according to one embodiment of the present invention are a non-magnetic steel material and a method for manufacturing the same. The steel material comprises 15-27 wt % of manganese, 0.1-1.1 wt % of carbon, 0.05-0.50 wt % of silicon, 0.03 wt % or less (0% exclusive) of phosphorus, 0.01 wt % or less (0% exclusive) of sulfur, 0.050 wt % or less (0% exclusive) of aluminum, 5 wt % or less (0% inclusive) of chromium, 0.01 wt % or less (0% inclusive) of boron, 0.1 wt % or less (0% exclusive) of nitrogen, and a balance amount of Fe and inevitable impurities, has an index of sensitivity of 3.4 or less, the index of sensitivity being represented by the following relational expression (1): [Relational expression 1]&#x2014;0.451+34.131*P+111.152*Al&#x2212;799.483*B+0.526*Cr&#x2264;3.4 (wherein [P], [Al], [B] and [Cr] each mean a wt % of corresponding elements), and contains a microstructure with austenite at an area fraction of 95% or greater therein.

Non-magnetic steel material having excellent hot workability and manufacturing method therefor

Provided is a steel having excellent weldability and impact toughness in a welding zone comprising: by weight (wt.) %, carbon (C): 0.1% to 0.3%, manganese (Mn): 11% to 13%, iron (Fe) as a residual component thereof, and other inevitable impurities, and positive and negative segregation zones in a layered form. The positive segregation zone comprises austenite and epsilon martensite, and the negative segregation zone comprises, by area fraction, epsilon martensite of less than 5% and alpha martensite.

Steel having excellent weldability and impact toughness of welding zone

The present invention relates to a high strength austenitic-based steel with remarkable toughness of a welding heat-affected zone and a preparation method therefor. One embodiment of the present invention provides: a high strength austenitic-based steel with remarkable toughness of a welding heat-affected zone, comprising 0.8-1.5 wt % of C, 15-22 wt % of Mn, 5 wt % or less of Cr (except 0), and the balance of Fe and other inevitable impurities, and further comprising at least one of the following (a) and (b), wherein the microstructure of a welding heat-affected zone comprises 90% or more of austenite by volume fraction; and a preparation method therefor. (a) Mo: 0.1-1% and B: 0.001-0.02% (b) Ti: 0.01-0.3% and N: 0.003-0.1%.

High strength austenitic-based steel with remarkable toughness of welding heat-affected zone and preparation method therefor

Disclosed herein is a nano device, including: a carbon layer including one-layered graphene having a honeycombed planar structure in which carbon atoms are connected with each other and two or more-layered monocrystalline graphite; and one or more vertically-grown nanostructures formed on the carbon layer. This nano device can be used to manufacture an integrated circuit in which various devices including a graphene electronic device and a photonic device are connected with each other, and is a high-purity and high-quality nano device having a small amount of impurities because a metal catalyst is not used.

Nano device integrated on graphene and monocrystalline graphite

Provided are a color to grayscale image conversion method of converting a color image into a grayscale image while maintaining original features of the color image, and a recording medium storing a program for performing the same. When an original color image is input, a target gradient with the features of the input original color image is acquired, and a global mapping function for converting the original color image into a grayscale image is determined based on the acquired target gradient. Thereafter, the original color image is converted into a grayscale image using the determined global mapping function. Therefore, it is possible to quickly convert a color image into a grayscale image, and to acquire a high-quality grayscale image with features of color difference included in the original color image.

Method of converting color image into grayscale image and recording medium storing program for performing the same

A field emission device, a field emission display device, and a method for manufacturing the same are disclosed. The field emission device includes: i) a substrate; ii) an electrode positioned on the substrate; iii) a mask layer positioned on the electrode and including one or more openings; and iv) a plurality of nanostructures positioned on the electrode via the openings and formed to extend radially. The plurality of nanostructures may be applied to emit an electron upon receiving a voltage from the electrode.

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Pohang-si, South Korea

Yong-Jin Kim