Analysis of compaction and sintering behavior of 316L stainless steel nano/micro bimodal powder

Oh, Joo Won,Ryu, Seung Kyu,Lee, Won Sik,Park, Seong Jin Elsevier 2017 Powder Technology Vol.322 No.-

<P><B>Abstract</B></P> <P>Nano powder had various advantages on powder metallurgy process. However, because of its high price and difficulties in treatment, nano powder cannot be easily applied to the field. As a result, nano/micro bimodal powder has been introduced to overcome such problems. In this study, the effects of nano powder ratio in nano/micro bimodal powder on powder metallurgy process have been investigated. The master sintering curves for the bimodal powders were also developed for the first time. With micro, nano and 3 different bimodal powders, compaction behavior was investigated, and dilatometric sintering was carried out to analyze the densification behavior during the sintering process. The results showed bimodal powders had relatively high green density, and the highest value was obtained with 25% nano bimodal powder. The powder also provided the highest densification parameter. Based on the dilatometer data, the master sintering curves of each powder were constructed, and all curves were consistent with experimental data.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nano powder effect in bimodal powders on powder metallurgy process was analyzed. </LI> <LI> 25% nano bimodal powder had the highest green density with bimodal packing effect. </LI> <LI> 25% nano bimodal powder had the highest densification parameter during sintering. </LI> <LI> Bimodal powders showed two-peak sintering behavior due to the nano powder. </LI> <LI> Master sintering curves were well-developed for nano/micro bimodal powders. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

분말송급장치의 개조에 의한 미세$5\mu\textrm{m}$ $Al_2O_3$분말의 송급 특성개선 및 플라즈마 용사조건에 따른 코팅층의 특성분석

설동욱,김병희,정민석,임영우,서동수 대한용접접합학회 1997 대한용접·접합학회지 Vol.15 No.1

A scope of this study is to establish the optimum plasma spray conditions for fine ($5\mu\textrm{m}$) $Al_2O_3$ powder. However, the flowability of the $Al_2O_3$ powder is not so good because of irregular particle shape and fine particle size. Therefore, powder feeding system was modified by 1) change of powder feeding line material from polymer to copper 2) shorten the powder feeding tube length 3) heating the powder feeding system to $80^{\circ}C$4) vibrating the powder feeding line continuously, in order to feed the fine powder homogeneously. The homogeneous powder feeding conditions were obtained with the modified powder feeding system by controlling the powder carrier gas flow and the powder flow rate indicator. The best plasma spraying conditions for the fine $Al_2O_3$ powder were found out as 40kw gun power, 80 g/min. powder feed rate and 50 mm working distance after characterizing the microstructure, hardness and wear loss of the $Al_2O_3$ coating layer.

Effects of material and processing conditions on powder-binder separation using the Taguchi method

Park, D.Y.,Shin, D.S.,Cho, H.,Park, S.J. Elsevier Sequoia 2017 Powder technology Vol.321 No.-

<P>The effects of material and processing conditions-powder size, injection temperature, initial powder volume fraction, and shear rate-on powder-binder separation in powder injection molding were investigated. A minimum set of experiments were performed based on the Taguchi method. The non-Newtonian viscosity model was employed to describe the rheological behavior of the feedstock. The critical solid loadings for the different powder sizes were determined by torque rheometry experiments. All other parameters for the viscosity model for the different powder sizes were obtained by capillary rheometry and linear fitting. The powder volume fractions along the radial direction of the polished surface were measured by image processing, based on the intensity difference between the powder and binder. The powder distribution profile was determined by a mean residual method. Powder-binder separation under the different processing and material conditions were quantitatively calculated by the definition of Variation. Finally, the effects of powder size, injection temperature, initial powder volume fraction, and shear rate were analyzed by the Taguchi method. Furthermore, the results of the Taguchi analysis were verified by additional experiments. (C) 2017 Elsevier B.V. All rights reserved.</P>

대두분과 청국장분 첨가가 제빵특성에 미치는 영향

고은숙 ( Eun Sook Ko ),이원종 ( Won Jong Lee ) 한국식품저장유통학회 ( 구 한국농산물저장유통학회 ) 2012 한국식품저장유통학회지 Vol.19 No.2

The effects of soybean powder and chungkukjang powder on the quality characteristics of bread were investigated. The nutritional elements of the soybena powder, chungkukjang powder and wheat flour differed remarkably. The average crude protein, ash, crude lipid, and fiber of soybean powder and chungkukjang powder were approximately 3, 15, 8 and 5 times higher than those of the wheat flour, respectively. The properties of the dough to which soybean powder and chungkukjang powder were added, i.e., its water absorption (%), development time (min) and stability (min) were measured with a farinograph. The water absorption, and development time of the farinogram increased, but its stability decreased when soybean powder and chungkukjang powder were added to white wheat flour. As long as the mixture rate of soybean powder and chungkukjang powder increased, the loaf volume of the bread declined, but the weight significantly increased. The L value decreased, but the a and b values increased in bread crumb that was made from soybean powder and chungkukjang powder. The white wheat flour to which 10% soybean powder and 5% chungkukjang powder were added had the highest scores in flavor, color, texture, taste, and overall acceptability in the sensory evaluation.

누룩 가루의 첨가량을 달리하여 제조한 베샤멜 소스의 품질 특성

이두진,유승석 (사)한국조리학회 2022 한국조리학회지 Vol.28 No.5

In this study, aims to investigate the functionality and preference of Béchamel sauce prepared using Nuruk powder, which is known as a food with excellent physiological activity. Nuruk powder prepared from Korean wheat was used, and a bechamel sauce was prepared to compare and analyze the quality characteristics and Sensory evaluation according to the different amount of Nuruk powder added. The pH tended to increase in accordance with the addition amount of the Nuruk powder. The moisture increased as the amount of Nuruk powder increased. The viscosity decreased as the addition of the amount of Nuruk powder increased. Among the chromaticity, the L value tended to decrease significantly as the Nuruk powder was added. The value of a tended to increase as Nuruk powder was added. The b value decreased significantly as the Nuruk powder was added. The reduced sugar of the Béchamel Sauce was the addition of the addition of Nuruk powder, the decreased the amount of the reduced sugar. The increase in the addition amount of the Nuruk powder increased, the increasing DPPH free radical erasure activity increased. As a result of the sensory evaluation of the Béchamel sauce the results of the sensor, the taste, texture, the mouth texture, and the overall symbol showed the highest symbol in the 15% added sample. Through this study, adding Nuruk powder to bechamel sauce can produce a sauce with high functionality and excellent overall taste, and furthermore, it is thought that there is a possibility of developing various foods using Nuruk powder.

토마토 가루를 첨가한 양갱의 품질특성

김경희(Kyoung-Hee Kim),김영식(Young Shik Kim),고종호(Jong-Ho Koh),홍민서(Min-Seo Hong),육홍선(Hong-Sun Yook) 한국식품영양과학회 2014 한국식품영양과학회지 Vol.43 No.7

This study examined the quality characteristics of Yanggaeng added with tomato powder (0, 5, 10, 15, and 20%) and oligosaccharides instead of red beans and sugar. The moisture content of tomato Yanggaeng was 45.89~33.64% and was highest in the control group. The pH ranged 3.96~6.24 and significant decreased with the addition of tomato powder. Hunter"s color value, lightness (L value) were the highest in Yanggaeng added with 20% tomato powder. Redness (a value) increased with tomato powder content, except for 20% tomato powder. Yellowness (b value) significantly increased with tomato powder content (P<0.05) but decreased with 20% tomato powder. In the texture profile analysis, hardness, cohesiveness, gumminess, and chewiness significantly decreased (P<0.05) with the addition of tomato powder. Total soluble solid content (°Brix) was the highest (5.16) in the control group, whereas that of tomato Yanggaeng ranged 4.46~4.92 and significantly decreased (P<0.05) with the addition of tomato powder. The antioxidative activity based on 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of Yanggaeng increased with the concentration of tomato powder, although those of Yanggaeng added with 15% and 20% tomato powder were not significantly different (P<0.05). Yanggaeng added with 5 and 10% tomato powder showed acceptable sensory properties, including color, flavor, sweet taste, sour taste, and overall quality. In terms of sensory evaluation and antioxidant activity, the results show that Yanggaeng added with 10% tomato powder was the best, but more research should be conducted in order to improve sensory acceptability.

한국산과 중국산 산사가루의 첨가량을 달리한 식빵의 품질특성연구

송태희 ( Tae Hee Song ),최희숙 ( Hee Sook Choi ),김용선 ( Yong Sun Kim ),우인애 ( In Ae Woo ) 한국식생활문화학회 2012 韓國食生活文化學會誌 Vol.27 No.4

In this study, the sensory and mechanical characteristics of white bread containing different levels of Korean and Chinese sansa powder were evaluated. Korean sansa was smaller and more reddish than that of Chinese sansa. Sansa powder contained ursolic acid, citric acids, and flavonoids, which have antioxidative effects. Contents of total flavonoids in Korean and Chinese sansa powder were 217.67±7.64 mg/100 g and 127.67±7.85 mg/100 g, respectively. The mechanical and sensory characteristics of bread added with different levels (0, 2, 4, and 6%) of Korean and Chinese sansa powder were evaluated. Lightness of crust and crumb of bread containing Korean sansa powder decreased as the level of Korean sansa powder increased, whereas they increased as the level of Chinese sansa powder increased. Mechanical texture parameters such as hardness and gumminess increased as the level of Korean and Chinese of sansa powder increased. In a sensory evaluation, control, bread containing 2 or 4% Korean sansa powder, and bread containing 2% Chinese sansa powder showed higher overall acceptability than the others. In conclusion, these results indicate that the recommended substitution level for sansa powder in bread is 2 or 4% Korean sansa powder and 2% Chinese sansa powder.

미나리분말 첨가 파운드케이크의 품질특성

안상희 ( Sang Hee An ) 한국식품조리과학회(구 한국조리과학회) 2014 한국식품조리과학회지 Vol.30 No.3

This study investigated the physicochemical and sensory characteristics of pound cake prepared with various amounts of dropwort powder. According to the results, the specific gravity of batter prepared with dropwort powder was increased, whereas the pH of batter was decreased significantly with the addition of dropwort powder. Furthermore, the weight of the pound cake prepared by adding 8% dropwort powder had the lowest among all samples. The volume and specific loaf volume of pound cakes prepared by adding dropwort powder were higher than those of the control. The baking loss rate of the control was 5.45% and that of pound cakes prepared by adding dropwort powder was 5.08~7.08%. In addition, the moisture content of pound cakes was found to increase with an increased in the amount of dropwort powder, whereas the pH of pound cakes was found to decrease with an increase in the dropwort powder content. The DPPH radical scavenging activity of the control group was 23.58%, whereas that of pound cakes prepared by adding dropwort powder ranged from 38.77~77.60%. However, the L, a and b values were decreased significantly by the addition of dropwort powder. The hardness, springiness, chewiness and brittleness of pound cakes were decreased significantly by the addition of dropwort powder. Overall, the sensory evaluation scores in terms of appearance, flavor, taste, texture and overall preference for pound cakes were conveyed to be higher in 4~6% of substituted sample groups than those of others. Hence, the results of this study suggest that addition of 4~6% dropwort powder is the best substitution ratio for pound cakes.

우엉분말을 첨가한 쿠키의 품질특성

김현용,김경희,육홍선,Kim, Hyun-Yong,Kim, Kyoung-Hee,Yook, Hong-Sun 한국식품조리과학회 2017 한국식품조리과학회지 Vol.33 No.3

Purpose: The study investigated the quality characteristics of cookies prepared 0, 10, 20 and 30% burdock (Arctium lappa L.) powder. Methods: Cookies were manufactured with 0%, 10%, 20%, and 30% wheat flour substituted for burdock powder. Results: Density of the dough showed no significant differences with increasing amount of burdock powder, whereas pH of the dough decreased with increasing burdock powder content. The pH of cookies decreased with increasing burdock powder content, whereas $^{\circ}brix$ of cookies increased with burdock powder content. The moisture contents of cookies increased with increasing burdock powder content. The spreadability of cookies decreased with increasing burdock powder content. The L-value of cookies decreased, a-value increased, and b-value decreased with increasing burdock powder content. The hardness of cookies decreased with increasing burdock powder content. Total polyphenol contents and DPPH radical scavenging activity increased with increasing burdock powder content (p<0.05). In the sensory evaluation, appearance, color, flavor, and texture were highest in the control group, whereas sweet taste and savory taste were highest in the added group. For overall acceptance of cookies, 10% burdock powder cookies showed higher values than the control and other samples. Conclusion: Results suggest that cookies manufactured with 10% burdock powder are the most optimal product.

경옥가루의 물리화학적 특성 및 화장품 제형 응용 연구

김경미 ( Kyoung Mi Kim ),김용우 ( Yong Woo Kim ),홍인기 ( In Gi Hong ),박수남 ( Soo Nam Park ) 한국공업화학회 2018 공업화학 Vol.29 No.1

본 연구에서는 천연 소재인 경옥가루의 물리화학적 특성을 조사하고 이를 함유한 워시오프 팩과 리퀴드 파운데이션을 제조하였다. 또한 이들 제형을 대상으로 각 제형이 주는 효과와 사용자 관능 평가, 제형 안정성 및 피부 안전성평가를 수행하였다. 워시오프 팩 중의 경옥가루의 함량이 증가할수록 원적외선 방사율과 방사에너지 값이 증가하였고, 경옥가루를 3% 함유한 제품에서는 피부 적용 시 피부 온도가 약 0.5 ℃ 상승하였다. 경옥가루를 첨가한 리퀴드 파운데이션은 피부 본래의 색을 더욱 선명하게 표현할 수 있는 채도를 나타냈다. 경옥가루를 첨가한 워시오프 팩과 리퀴드 파운데이션은 각각의 수분 보유량이 최대 5.0% 및 63.0%로 나타났다. 사용자 관능 평가에서 경옥가루를 함유한 워시오프 팩 제형은 피부친화력, 밀착력, 가려움 및 촉촉함을 개선시켰다. 경옥가루를 함유한 리퀴드 파운데이션도 대조군 제형과 비교했을 때 커버력을 제외한 모든 항목에서 개선이 이루어졌다. 경옥가루 함유 제형에 대해 8주간 안정성 평가를 한 결과 육안상으로 변색이나 분리현상은 관찰되지 않았으며 pH는 8주까지, 점도는 4주까지 안정함을 확인하였다. 또한, 피부 안전성 평가에서 경옥가루 함유 제형은 모두 자극이 없는 것으로 나타났다. 결론적으로, 경옥가루는 무기안료로써 안정성과 안전성이 확보된 새로운 다기능 소재로써 화장품에 응용 가능성이 있음을 시사하였다. In this study, physicochemical properties of the natural jadeite powder were investigated and also the wash-off pack and liquid foundation containing the jadeite powder were prepared. In addition, each of these formulations was evaluated by various functional effects, sensory evaluation, stability and skin safety. In the wash-off pack, the far-infrared ray emissivity and radiation energy values increased as a function of the jadeite powder content. At a 3% jadeite powder content, the skin temperature increased by about 0.5 ℃ when the jadeite powder-containing formulation was applied to the skin. Besides, the chroma of the liquid foundation containing the jadeite powder more clearly expressed the original color of the skin. Moisture content measurements of the wash-off pack and liquid foundation containing the jadeite powder showed the highest moisture uptake of 5.0% and 63.0%, respectively. In sensorial test, the wash-off pack formulations containing the jadeite powder demonstrated improved affinities toward a skin, adherency, and moistness and combatted itching. The liquid foundation containing jadeite powder showed also improved affinities except for the coverage when compared to control formulations. Furthermore, the stability evaluation for 8 weeks revealed neither discoloration nor separation phenomenon for the formulations containing the jadeite powder. Moreover, the pH was found to be stable up to 8 weeks and the viscosity up to 4 weeks. Skin safety assessments showed that all formulations containing the jadeite powder were non-irritating. These results suggest that the jadeite powder as an inorganic pigment may serve as a new multi-functional cosmetic ingredient with stability and safety.