Abstract
Advanced high-strength M190 steel sheets were joined by friction-stir welding under different tool rotational and traversing speeds. the optical microstructure of the joints exhibited complete martensite and partial martensite at the weld nugget depending on the cooling rate during welding. the first heat-affected zone outside of the weld nugget revealed ferrite-pearlite phase aggregate, and the second heat-affected zone showed a tempered martensitic structure. the interplay of process variables in terms of peak temperature and cooling rate was studied to observe their effect on joint efficiency under shear testing. the peak hardness at weld nugget was close to the parent alloy at an intermediate cooling rate of 294 to 313 K/s. the lowest hardness was observed at the first heat-affected zone for all welded joints. Joint efficiency was dependent on relative quantity of ferrite-pearlite at first heat-affected zone. in that respect, the intermediate temperature to the tune of ̃1193 K to 1273 K (̃920 °C to 1000 °C) at the weld nugget was found to be beneficial for obtaining an adequate quantity of pearlite at the first heat-affected zone to provide joint efficiency of more than 50 pct of that of parent alloy. © the Minerals, Metals & Materials Society and ASM International 2012.
Recommended Citation
M. Ghosh et al., "Process Optimization for Friction-stir-welded Martensitic Steel," Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, vol. 43, no. 6, pp. 1966 - 1975, Springer; ASM International, Jun 2012.
The definitive version is available at https://doi.org/10.1007/s11661-012-1084-x
Department(s)
Materials Science and Engineering
International Standard Serial Number (ISSN)
1073-5623
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Springer; ASM International, All rights reserved.
Publication Date
01 Jun 2012
