Number of the records: 1

Microstructural characterization of laser weld of hot-stamped Al-Si coated 22MnB5 and modification of weld properties by hybrid welding

SYSNO ASEP	0544220
Document Type	J - Journal Article
R&D Document Type	Journal Article
Subsidiary J	Článek ve WOS
Title	Microstructural characterization of laser weld of hot-stamped Al-Si coated 22MnB5 and modification of weld properties by hybrid welding
Author(s)	Šebestová, Hana (UPT-D)_{RID, ORCID, SAI} Horník, Petr (UPT-D)_{RID, ORCID, SAI} Mikmeková, Šárka (UPT-D)_{RID, SAI, ORCID} Mrňa, Libor (UPT-D)_{RID, ORCID, SAI} Doležal, P. (CZ) Novotný, Jan (UPT-D)_{ORCID, SAI, RID}
Number of authors	6
Article number	3943
Source Title	Materials. - : MDPI Roč. 14, č. 14 (2021)
Number of pages	15 s.
Publication form	Online - E
Language	eng - English
Country	CH - Switzerland
Keywords	22MnB5 ; laser welding ; hybrid welding ; cooling rate ; tensile strength ; microstructure ; microhardness
Subject RIV	JR - Other Machinery
OECD category	Mechanical engineering
R&D Projects	TH04010366 GA TA ČR - Technology Agency of the Czech Republic (TA ČR)
Method of publishing	Open access
Institutional support	UPT-D - RVO:68081731
UT WOS	000676610300001
EID SCOPUS	85111455543
DOI	10.3390/ma14143943
Annotation	The presence of Al-Si coating on 22MnB5 leads to the formation of large ferritic bands in the dominantly martensitic microstructure of butt laser welds. Rapid cooling of laser weld metal is responsible for insufficient diffusion of coating elements into the steel and incomplete homogenization of weld fusion zone. The Al-rich regions promote the formation of ferritic solid solution. Soft ferritic bands cause weld joint weakening. Laser welds reached only 64% of base metal's ultimate tensile strength, and they always fractured in the fusion zone during the tensile tests. We implemented hybrid laser-TIG welding technology to reduce weld cooling rate by the addition of heat of the arc. The effect of arc current on weld microstructure and mechanical properties was investigated. Thanks to the slower cooling, the large ferritic bands were eliminated. The hybrid welds reached greater ultimate tensile strength compared to laser welds. The location of the fracture moved from the fusion zone to a tempered heat-affected zone characterized by a drop in microhardness. The minimum of microhardness was independent of heat input in this region.
Workplace	Institute of Scientific Instruments
Contact	Martina Šillerová, sillerova@ISIBrno.Cz, Tel.: 541 514 178
Year of Publishing	2022
Electronic address	https://www.mdpi.com/1996-1944/14/14/3943

Number of the records: 1