{"title":"Development of process-structure linkage for Inconel 718 processed by laser powder bed fusion: a numerical modeling approach","authors":"Anuj Kumar, Mukul Shukla","doi":"10.1108/rpj-02-2023-0064","DOIUrl":null,"url":null,"abstract":"Purpose Understanding and tailoring the solidification characteristics and microstructure evolution in as-built parts fabricated by laser powder bed fusion (LPBF) is crucial as they influence the final properties. Experimental approaches to address this issue are time and capital-intensive. This study aims to develop an efficient numerical modeling approach to develop the process–structure (P-S) linkage for LPBF-processed Inconel 718. Design/methodology/approach In this study, a numerical approach based on the finite element method and cellular automata was used to model the multilayer, multitrack LPBF build for predicting the solidification characteristics (thermal gradient G and solidification rate R) and the average grain size. Validations from published experimental studies were also carried out to ensure the reliability of the proposed numerical approach. Furthermore, microstructure simulations were used to develop P-S linkage by evaluating the effects of key LPBF process parameters on G × R, G/R and average grain size. A solidification or G-R map was also developed to comprehend the P-S linkage. Findings It was concluded from the developed G-R map that low laser power and high scan speed will result in a finer microstructure due to an increase in G × R, but due to a decrease in G/R, columnar characteristics are also reduced. Moreover, increasing the layer thickness and decreasing the hatch spacing lowers the G × R, raises the G/R and generates a coarse columnar microstructure. Originality/value The proposed numerical modeling approach was used to parametrically investigate the effect of LPBF parameters on the resulting microstructure. A G-R map was also developed that enables the tailoring of the as-built LPBF microstructure through solidification characteristics by tuning the process parameters.","PeriodicalId":20981,"journal":{"name":"Rapid Prototyping Journal","volume":null,"pages":null},"PeriodicalIF":3.4000,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Rapid Prototyping Journal","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1108/rpj-02-2023-0064","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose Understanding and tailoring the solidification characteristics and microstructure evolution in as-built parts fabricated by laser powder bed fusion (LPBF) is crucial as they influence the final properties. Experimental approaches to address this issue are time and capital-intensive. This study aims to develop an efficient numerical modeling approach to develop the process–structure (P-S) linkage for LPBF-processed Inconel 718. Design/methodology/approach In this study, a numerical approach based on the finite element method and cellular automata was used to model the multilayer, multitrack LPBF build for predicting the solidification characteristics (thermal gradient G and solidification rate R) and the average grain size. Validations from published experimental studies were also carried out to ensure the reliability of the proposed numerical approach. Furthermore, microstructure simulations were used to develop P-S linkage by evaluating the effects of key LPBF process parameters on G × R, G/R and average grain size. A solidification or G-R map was also developed to comprehend the P-S linkage. Findings It was concluded from the developed G-R map that low laser power and high scan speed will result in a finer microstructure due to an increase in G × R, but due to a decrease in G/R, columnar characteristics are also reduced. Moreover, increasing the layer thickness and decreasing the hatch spacing lowers the G × R, raises the G/R and generates a coarse columnar microstructure. Originality/value The proposed numerical modeling approach was used to parametrically investigate the effect of LPBF parameters on the resulting microstructure. A G-R map was also developed that enables the tailoring of the as-built LPBF microstructure through solidification characteristics by tuning the process parameters.
期刊介绍:
Rapid Prototyping Journal concentrates on development in a manufacturing environment but covers applications in other areas, such as medicine and construction. All papers published in this field are scattered over a wide range of international publications, none of which actually specializes in this particular discipline, this journal is a vital resource for anyone involved in additive manufacturing. It draws together important refereed papers on all aspects of AM from distinguished sources all over the world, to give a truly international perspective on this dynamic and exciting area.
-Benchmarking – certification and qualification in AM-
Mass customisation in AM-
Design for AM-
Materials aspects-
Reviews of processes/applications-
CAD and other software aspects-
Enhancement of existing processes-
Integration with design process-
Management implications-
New AM processes-
Novel applications of AM parts-
AM for tooling-
Medical applications-
Reverse engineering in relation to AM-
Additive & Subtractive hybrid manufacturing-
Industrialisation