TY - JOUR
T1 - Grain refinement in additively manufactured ferritic stainless steel by in situ inoculation using pre-alloyed powder
AU - Durga, A.
AU - Pettersson, Niklas Holländer
AU - Malladi, Sri Bala Aditya
AU - Chen, Zhuoer
AU - Guo, Sheng
AU - Nyborg, Lars
AU - Lindwall, Greta
N1 - Funding Information:
This study was performed within the strategic innovation program Metalliska Material through the project Design of novel materials and processes for next generation additive manufacturing (DEMA), financed by the Swedish Governmental Agency for Innovation Systems (VINNOVA), Formas and Energimyndigheten. The industrial project partners Höganäs AB, Kanthal AB, Quintus Technologies AB, Sandvik Materials Technology and Jernkontoret are acknowledged for valuable input. Roger Berglund, Kanthal AB, is acknowledged for materials supply, chemical analysis and valuable discussions. LN and GL also acknowledge support from VINNOVA via LIGHTer Academy.
Publisher Copyright:
© 2020
PY - 2021/3/15
Y1 - 2021/3/15
N2 - For ferritic stainless steels, TiN has effectively been used as an inoculant to produce equiaxed grain structures in casting and welding. However, it is not established whether TiN would be an effective inoculant in additive manufacturing. In this study, the effectiveness of TiN as an inoculant in a ferritic stainless steel processed by laser powder-bed fusion is studied. An alloy without Ti is fabricated and compared to an alloy designed to form a high amount of TiN early during solidification. The work shows that the presence of TiN provides general grain refinement and that TiN-covered oxide particles are effective in enabling columnar-to-equiaxed transition in certain regions of the meltpool. The applied approach of pre-alloying powders with inoculant-forming elements offers a straightforward route to achieving fine, equiaxed grain structures in additively manufactured metallic materials. It also shows how oxygen present during the process can be utilized to nucleate effective inoculating phases.
AB - For ferritic stainless steels, TiN has effectively been used as an inoculant to produce equiaxed grain structures in casting and welding. However, it is not established whether TiN would be an effective inoculant in additive manufacturing. In this study, the effectiveness of TiN as an inoculant in a ferritic stainless steel processed by laser powder-bed fusion is studied. An alloy without Ti is fabricated and compared to an alloy designed to form a high amount of TiN early during solidification. The work shows that the presence of TiN provides general grain refinement and that TiN-covered oxide particles are effective in enabling columnar-to-equiaxed transition in certain regions of the meltpool. The applied approach of pre-alloying powders with inoculant-forming elements offers a straightforward route to achieving fine, equiaxed grain structures in additively manufactured metallic materials. It also shows how oxygen present during the process can be utilized to nucleate effective inoculating phases.
KW - Columnar-to-equiaxed transition
KW - Ferritic stainless steels
KW - Inoculation
KW - Laser Powder-Bed Fusion
KW - Solidification
UR - http://www.scopus.com/inward/record.url?scp=85098763918&partnerID=8YFLogxK
U2 - 10.1016/j.scriptamat.2020.113690
DO - 10.1016/j.scriptamat.2020.113690
M3 - Article
AN - SCOPUS:85098763918
SN - 1359-6462
VL - 194
JO - Scripta Materialia
JF - Scripta Materialia
M1 - 113690
ER -