[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-665632-105":59,"doc-detail-665632-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","continuous-cooling-transformation-cct-determination-of-cct-diagram-type-i","Continuous Cooling Transformation (CCT) - Determination of CCT diagram type I","","Continuous Cooling Transformation (CCT) diagrams describe how phases remain stable and evolve during continuous cooling of austenite. The document outlines two common CCT diagram types and focuses on type I, where transformation start, specific fraction, and finish temperatures are plotted against transformation time along each cooling curve. It details dilatometric determination using dilatometer measurements—tracking dilation vs temperature to identify slope changes that mark phase transformations—supplemented by metallography and hardness tests to interpret product nature and transformation fractions.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/continuous-cooling-transformation-cct-determination-of-cct-diagram-type-i/665632/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/continuous-cooling-transformation-cct-determination-of-cct-diagram-type-i/665632.png","ImageObject",300,407,{"name":92,"@type":93},"Quinn Holloway","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-30","2026-10-29",true,{"@type":102,"interactionType":103,"userInteractionCount":81},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What does a CCT diagram represent during continuous cooling of austenite?","Question",{"text":112,"@type":113},"A CCT diagram represents the stability and evolution of phases during continuous cooling, showing transformation start, fraction of transformation, and transformation finish temperatures along cooling schedules.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How is CCT diagram type I determined experimentally?",{"text":117,"@type":113},"Type I is determined by measuring physical properties during continuous cooling, commonly using specific volume change from dilatometric methods. Dilation vs temperature is recorded and slope changes identify phase transformations.",{"name":119,"@type":110,"acceptedAnswer":120},"Why do dilation–temperature curves show slope changes at transformation start and finish temperatures?",{"text":121,"@type":113},"Slope changes occur because phase transformations alter the relative phase amounts in addition to thermal specific volume effects. The onset of transformation is marked when the curve slope changes, and completion corresponds to the next consistent slope region.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},665632,1793305320,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":81,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":129,"read_time":144},2336474466712,"https://ap-avatar.wpscdn.com/davatar_a8503ba1806abce46bf441b54a3ca4cd","Continuous Cooling Transformation (CCT)  \nDiagrams  \nR. Manna  \nAssistant Professor  \nCentre of Advanced Study Department of Metallurgical Engineering  \nInstitute of Technology, Banaras Hindu University  \nVaranasi-221 005, India  \n[rmanna.met@itbhu.ac.in](rmanna.met@itbhu.ac.in)  \nTata Steel-TRAERF Faculty Fellowship Visiting Scholar Department of Materials Science and Metallurgy  \nUniversity of Cambridge, Pembroke Street, Cambridge, CB2 3QZ  \n[rm659@cam.ac.uk](rm659@cam.ac.uk)  \nContinuous cooling transformation (CCT) diagram  \nDefinition: Stability of phases during continuous  \ncooling of austenite  \nThere are two types ofCCT diagrams  \nI) Plot of (for each type of transformation) transformation start, specific fraction of transformation and transformation finish temperature against transformation time on each cooling curve  \nII) Plot of (for each type of transformation) transformation start, specific fraction of transformation and transformation finish temperature against cooling rate or bar diameter for each type of cooling medium 2  \nDetermination of CCT diagram type I  \nCCT diagrams are determined by measuring some physical properties during continuous cooling. Normally these are specific volume and magnetic permeability. However, the majority of the work has been done through specific volume change by dilatometric method. This method is supplemented by metallography and hardness measurement.  \nIn dilatometry the test sample (Fig. 1) is austenitised in a specially designed furnace (Fig. 2) and then controlled cooled. Sample dilation is measured by dial gauge/sensor. Slowest cooling is controlled by furnace cooling but higher cooling rate can be controlled by gas quenching.  \nFig. 1: Sample and fixtures for Fig. 2 : Dilatometer equipment dilatometric measurements  \n\n| Cooling data are plotted as temperature versus time (Fig. 3) . Dilation is recorded against temperature (Fig. 4) . Any slope change indicates phase transformation. Fraction of transformation roughly can be calculated based on the dilation data as explained below. |  |  |\n| --- | --- | --- |\n| | | For a cooling schedule\u003Cbr>d\u003Cbr>a\u003Cbr>c\u003Cbr>b\u003Cbr>TF TS\u003Cbr>\u003Cbr>\u003Cbr>X\u003Cbr>Y\u003Cbr>Z\u003Cbr>T |\n| Time Temperature  |  |  |\n\nFig. 3: Schematic cooling curves  \nFig. 4: Dilation-temperature plot  \nfor a cooling curve 5  \nTemperature  \nDilation  \nIn Fig. 3 curves I to V indicate cooling curves at higher cooling rate to lower cooling rate respectively. Fig. 4 gives the dilation at different temperatures for a given cooling rate/schedule. In general slope of dilation curve remains unchanged while amount of phase or the relative amount of phases in a phase mixture does not change during cooling (or heating) however sample shrink or expand i.e. dilation takes place purely due to thermal specific volume change because of change in temperature. Therefore in Fig. 4 dilation from a to bis due to specific volume change of high temperature phase austenite. But at TS slope of the curve changes. Therefore transformation starts at TS . Again slope of the curve from c tod is constant but is different from the slope of the curve from ato b. This indicates there is no phase transformation between the temperature from c to d but the phase/phase mixture is different from the phase at a to b.  \nSlope of the dilation curve from b to c is variable with temperature. This indicates the change in relative amount of phase due to cooling. The expansion is due to the formation of low density phase(s) . Some part of dilation is compensated by purely thermal change due to cooling. Therefore dilation curve takes complex shape. i.e first slope reduces and reaches to a minimum value and then increases to the characteristic value of the phase mixture at c.  \nTherefore phase transformation start at b i.e. at temperature TSand transformation ends or finishes at c or temperature TF. The nature of transformation has to be determined by metallography. When austenite fully transforms to a single product then amount of t","cbCailniL2gryePX","https://ap.wps.com/l/cbCailniL2gryePX","pdf",593827,33,"English","# Continuous Cooling Transformation (CCT)\n## Definition and diagram types\n## Determination of CCT diagram type I\n## Dilatometric method and measurement setup\n## Interpreting dilation–temperature curves\n## Transformation start, finish, and isopercentage concepts\n## Examples for cooling schedules and microstructural products","[{\"question\":\"What does a CCT diagram represent during continuous cooling of austenite?\",\"answer\":\"A CCT diagram represents the stability and evolution of phases during continuous cooling, showing transformation start, fraction of transformation, and transformation finish temperatures along cooling schedules.\"},{\"question\":\"How is CCT diagram type I determined experimentally?\",\"answer\":\"Type I is determined by measuring physical properties during continuous cooling, commonly using specific volume change from dilatometric methods. Dilation vs temperature is recorded and slope changes identify phase transformations.\"},{\"question\":\"Why do dilation–temperature curves show slope changes at transformation start and finish temperatures?\",\"answer\":\"Slope changes occur because phase transformations alter the relative phase amounts in addition to thermal specific volume effects. The onset of transformation is marked when the curve slope changes, and completion corresponds to the next consistent slope region.\"}]","Continuous Cooling Transformation (CCT) - Determination of CCT diagram type I | PDF",83]