[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-detail-657739-en":59,"doc-seo-657739-105":80},{"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":5,"data":60},{"doc_id":61,"user_id":62,"nickname":63,"user_avatar":64,"doc_module":4,"category_id":29,"category_name":30,"doc_title":65,"doc_description":66,"doc_content":67,"file_id":68,"file_url":69,"file_type":70,"file_size":71,"view_count":19,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":72,"language":73,"language_code":74,"site_id":75,"html_lang":74,"table_of_contents":76,"faqs":77,"seo_title":78,"seo_description":66,"update_tm":79,"read_time":36},657739,137455076865,"Aran","https://ap-avatar.wpscdn.com/davatar_29158cc5080c5b710cf443261637dec0","Transformation Diagram Computation - Model Definition - Results and Discussion","Transformation diagram computation for steel quenching is described through construction of CCT (continuous cooling transformation) and TTT (time-temperature transformation) diagrams. The workflow imposes temperature histories without geometry or full heat-transfer analysis, using parameter ranges for high/low temperatures, cooling-rate bounds, and a start phase fraction threshold. Austenite decomposition is modeled via the Leblond–Devaux approach, with temperature-dependent functions for ferrite and bainite. Computed diagrams are interpreted using representative cooling rates and transformation start times and temperatures.","Transformation Diagram Computation  \nThis model is licensed under the COMSOL Software License Agreement 6.2.  \nAll trademarks are the property of their respective owners. See [www.comsol.com/trademarks](www.comsol.com/trademarks).  \nDuring quenching of steel, the austenite decomposes into destination phases such as ferrite, pearlite, bainite, and martensite. The resulting phase composition depends to a large extent on the temperature history, and also on the chemical composition and austenite grain size. A common way to illustrate the phase transformation characteristics is to use transformation diagrams. Two of the most commonly used diagram types are the CCT (continuous cooling transformation) and the TTT (time-temperature transformation) diagrams. In the former, the austenitized material is cooled at a constant temperature rate, while in the latter, the material is kept at a constant temperature. Figure 1 shows an example CCT diagram, with temperature on the vertical axis, and logarithmic time on the horizontal. Fs, Ps, and Bs represent the start temperatures, at a given cooling rate, for the formation of, respectively, ferrite, pearlite, and bainite. The example CCT diagram shows that a cooling rate of 10 K/s is sufficient to suppress the formation of pearlite, whereas 1 K/s is not.  \nFigure 1: A CCT diagram.  \nA TTT diagram differs from a CCT diagram in that the austenite is rapidly cooled to a given initial temperature T0, and then kept at that temperature, see Figure 2 . This is performed for a range of start temperatures, and the transformation curves are constructed from the different times required to form a given phase. In a practical quenching situation, it is unlikely that material points will experience either of the two temperature histories that the CCT and TTT diagrams use, and instead experience varying temperature rates.  \n2 | T R A N S F O R M A T I O N D I A G R A M C O M P U T A T I O N  \nNevertheless, the diagrams can give useful insights into the phase transformation behavior of a certain material.  \nFigure 2: A TTT diagram.  \nIn this model, CCT and TTT diagrams are constructed from a set of phase-transformation model data using the methods described above.  \nModel Definition  \nIn order to compute transformation diagrams, no geometry is required, and suitable temperature histories can be accomplished without the need for a full heat-transfer analysis. The temperature is imposed as a parameter in the analysis. A number of parameters are used to compute the CCT and TTT diagrams. The diagrams are computed over a range of temperatures bounded by a lowest and a highest temperature. In the case of the CCT diagram computation, the cooling rate is additionally bounded by a lowest anda highest rate. The time-temperature combinations that illustrate the start of transformation in the CCT and TTT diagrams are obtained when a given phase reaches a defined (small) fraction. Table 1 shows these parameters.  \nTABLE 1: PARAMETERS USED IN THE MODEL DEFINITION.  \n\n| Name | Value | Description |\n| --- | --- | --- |\n| highT | 900 °C | Highest transformation temperature |\n| lowT | 100 °C | Lowest transformation temperature |\n| startFraction | 0.01 | Phase fraction indicating transformation start |\n\n3 | T R A N S F O R M A T I O N D I A G R A M C O M P U T A T I O N  \nTABLE 1: PARAMETERS USED IN THE MODEL DEFINITION.  \n\n| Name | Value | Description |\n| --- | --- | --- |\n| highRate | 100 K/s | Highest cooling rate for CCT |\n| lowRate | 0.01 K/s | Lowest cooling rate for CCT |\n\nPH AS E T RAN SF ORMA TI ON S  \nFor simplicity, the model only considers austenite decomposition into a combination offerrite and bainite, but it can straightforwardly be extended to include other destination phases as well.  \nAustenite to Ferrite  \nThe phase transformation is modeled using the Leblond-Devaux phase transformation model. The temperature dependent functions describing this transformation are given in Table 2 .  \nTABLE 2: AUSTENITE TO FERR","cbCaig8Ce1JI90zT","https://ap.wps.com/l/cbCaig8Ce1JI90zT","pdf",194014,16,"English","en",105,"# Transformation Diagram Computation\n## Model Definition\n## Austenite to Ferrite\n## Austenite to Bainite\n## Results and Discussion","[{\"question\":\"What are CCT and TTT diagrams used for in this model?\",\"answer\":\"They illustrate phase transformation characteristics during steel quenching. CCT uses continuous cooling at a constant rate, while TTT keeps the material at a constant temperature after rapid cooling to an initial value.\"},{\"question\":\"How are transformation diagrams computed without geometry in this model?\",\"answer\":\"Temperature is imposed as an analysis parameter, and CCT/TTT diagrams are computed over defined temperature ranges using model parameters. No full heat-transfer analysis is required.\"},{\"question\":\"Which phase transformations does the model consider for austenite decomposition?\",\"answer\":\"For simplicity, it considers austenite decomposition into ferrite and bainite. The text notes the approach can be extended to include other destination phases.\"}]","Transformation Diagram Computation - Model Definition - Results and Discussion | PDF",1792987716,{"code":4,"msg":81,"data":82},"ok",{"site_id":75,"language":74,"slug":83,"title":65,"keywords":84,"description":66,"schema_data":85,"social_meta":139,"head_meta":141,"extra_data":143,"updated_unix":144},"transformation-diagram-computation-model-definition-results-and-discussion","",{"@graph":86,"@context":138},[87,101,121],{"@type":88,"itemListElement":89},"BreadcrumbList",[90,94,96,99],{"item":91,"name":92,"@type":93,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":95,"name":9,"@type":93,"position":14},"https://docshare.wps.com/document/",{"item":97,"name":30,"@type":93,"position":98},"https://docshare.wps.com/document/technology/",3,{"item":100,"name":65,"@type":93,"position":19},"https://docshare.wps.com/document/transformation-diagram-computation-model-definition-results-and-discussion/657739/",{"url":100,"name":65,"@type":102,"image":103,"author":108,"headline":65,"publisher":110,"fileFormat":113,"inLanguage":74,"description":66,"dateModified":114,"datePublished":115,"encodingFormat":113,"isAccessibleForFree":116,"interactionStatistic":117},"DigitalDocument",{"url":104,"@type":105,"width":106,"height":107},"https://docshare.wps.com/thumbnails/transformation-diagram-computation-model-definition-results-and-discussion/657739.png","ImageObject",300,407,{"name":63,"@type":109},"Person",{"url":91,"name":111,"@type":112},"DocShare","Organization","application/pdf","2026-10-30","2026-10-26",true,{"@type":118,"interactionType":119,"userInteractionCount":19},"InteractionCounter",{"@type":120},"ViewAction",{"@type":122,"mainEntity":123},"FAQPage",[124,130,134],{"name":125,"@type":126,"acceptedAnswer":127},"What are CCT and TTT diagrams used for in this model?","Question",{"text":128,"@type":129},"They illustrate phase transformation characteristics during steel quenching. CCT uses continuous cooling at a constant rate, while TTT keeps the material at a constant temperature after rapid cooling to an initial value.","Answer",{"name":131,"@type":126,"acceptedAnswer":132},"How are transformation diagrams computed without geometry in this model?",{"text":133,"@type":129},"Temperature is imposed as an analysis parameter, and CCT/TTT diagrams are computed over defined temperature ranges using model parameters. No full heat-transfer analysis is required.",{"name":135,"@type":126,"acceptedAnswer":136},"Which phase transformations does the model consider for austenite decomposition?",{"text":137,"@type":129},"For simplicity, it considers austenite decomposition into ferrite and bainite. The text notes the approach can be extended to include other destination phases.","https://schema.org",{"og:url":100,"og:type":140,"og:title":65,"og:site_name":111,"og:description":66},"article",{"robots":142,"canonical":100},"index,follow",{"doc_id":61,"site_id":75},1793073088]