{"id":10116,"date":"2016-09-25T09:07:50","date_gmt":"2016-09-25T09:07:50","guid":{"rendered":"http:\/\/revoscience.com\/en\/?p=10116"},"modified":"2016-09-25T10:03:41","modified_gmt":"2016-09-25T10:03:41","slug":"stronger-turbine-blades-with-molybdenum-silicides","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/stronger-turbine-blades-with-molybdenum-silicides\/","title":{"rendered":"Stronger turbine blades with molybdenum silicides"},"content":{"rendered":"<p style=\"text-align: justify;\"><span style=\"color: #000000;\"><em><strong style=\"color: #000000;\">Researchers at Kyoto University have found that molybdenum silicides can improve the efficiency of turbine blades in ultrahigh-temperature combustion systems.<\/strong><\/em><\/span><\/p>\n<figure id=\"attachment_10117\" aria-describedby=\"caption-attachment-10117\" style=\"width: 570px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-10117\" src=\"http:\/\/revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg\" alt=\"Figure (left): Electron micrographs of directionally solidified (DS) ingots of binary composites. (right): Temperature dependence of yield stress of DS MoSi2\/Mo5Si3 eutectic composites and some high-temperature materials. \u00a92016 Hirotaka Matsunoshita, Yuta Sasai, Kosuke Fujiwara, Kyosuke Kishida and Haruyuki Inui.\" width=\"570\" height=\"279\" title=\"\" srcset=\"https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg 570w, https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908-300x146.jpg 300w\" sizes=\"auto, (max-width: 570px) 100vw, 570px\" \/><figcaption id=\"caption-attachment-10117\" class=\"wp-caption-text\"><\/span><\/a><\/span> <span style=\"color: #000000;\">Figure (left): Electron micrographs of directionally solidified (DS) ingots of binary composites. (right): Temperature dependence of yield stress of DS MoSi2\/Mo5Si3 eutectic composites and some high-temperature materials. \u00a92016 Hirotaka Matsunoshita, Yuta Sasai, Kosuke Fujiwara, Kyosuke Kishida and Haruyuki Inui.<\/span><\/figcaption><\/figure>\n<p style=\"text-align: justify;\"><span style=\"font-weight: normal; color: #000000;\">Gas turbines are the engines that generate electricity in power plants. The operating temperatures of their combustion systems can exceed 1600 \u00b0C. The nickel-based turbine blades used in these systems melt at temperatures 200 \u00b0C lower and thus require air-cooling to function. Turbine blades made out of materials with higher melting temperatures would require less fuel consumption and lead to lower CO2 emissions.\u00a0<\/span><br style=\"font-weight: normal; color: #000000;\" \/><br style=\"font-weight: normal; color: #000000;\" \/><span style=\"font-weight: normal; color: #000000;\">Materials scientists at Japan\u2019s Kyoto University investigated the properties of various compositions of molybdenum silicides, with and without additional ternary elements.\u00a0<\/span><br style=\"font-weight: normal; color: #000000;\" \/><br style=\"font-weight: normal; color: #000000;\" \/><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\">[pullquote]The team found that a homogeneous material could be formed by controlling the solidification rate of the molybdenum silicide-based composite during fabrication and by adjusting the amount of the ternary element added to the composite.\u00a0[\/pullquote]<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"font-weight: normal; color: #000000;\">Previous research showed that fabricating molybdenum silicide-based composites by pressing and heating their powders \u2013 known as powder metallurgy \u2013 improved their resistance to fracturing at ambient temperatures but lowered their high-temperature strength, due to the development of silicon dioxide layers within the material.\u00a0<\/span><br style=\"font-weight: normal; color: #000000;\" \/><br style=\"font-weight: normal; color: #000000;\" \/><span style=\"font-weight: normal; color: #000000;\">The Kyoto University team fabricated their molybdenum silicide-based materials using a method known as \u201cdirectional solidification,\u201d in which molten metal progressively solidifies in a certain direction.<\/span><br style=\"font-weight: normal; color: #000000;\" \/><br style=\"font-weight: normal; color: #000000;\" \/><span style=\"font-weight: normal; color: #000000;\">The team found that a homogeneous material could be formed by controlling the solidification rate of the molybdenum silicide-based composite during fabrication and by adjusting the amount of the ternary element added to the composite.\u00a0<\/span><br style=\"font-weight: normal; color: #000000;\" \/><br style=\"font-weight: normal; color: #000000;\" \/><span style=\"font-weight: normal; color: #000000;\">The resulting material starts deforming plastically under uniaxial compression above 1000 \u00b0C. Also, the material\u2019s high-temperature strength increases through microstructure refinement. Adding tantalum to the composite is more effective than adding vanadium, niobium or tungsten for improving the strength of the material at temperatures around 1400 \u00b0C. The alloys fabricated by the Kyoto University team are much stronger at high temperatures than modern nickel-based superalloys as well as recently developed ultrahigh-temperature structural materials, the researchers report in their study published in the journal Science and Technology of Advanced Materials.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Gas turbines are the engines that generate electricity in power plants. The operating temperatures of their combustion systems can exceed 1600 \u00b0C. The nickel-based turbine blades used in these systems melt at temperatures 200 \u00b0C lower and thus require air-cooling to function. Turbine blades made out of materials with higher melting temperatures would require less fuel consumption and lead to lower CO2 emissions. <\/p>\n","protected":false},"author":6,"featured_media":10117,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17],"tags":[],"class_list":["post-10116","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908-150x150.jpg",150,150,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908-300x146.jpg",300,146,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",550,269,false],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",95,47,false],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",570,279,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",96,47,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/09\/3908.jpg",150,73,false]},"author_info":{"info":["Amrita Tuladhar"]},"category_info":"<a href=\"https:\/\/www.revoscience.com\/en\/category\/news\/research\/\" rel=\"category tag\">Research<\/a>","tag_info":"Research","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/10116","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=10116"}],"version-history":[{"count":0,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/10116\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/10117"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=10116"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=10116"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=10116"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}