Joining dissimilar metal of Ti and CoCrMo using directed energy deposition

Cited 0 time in webofscience Cited 0 time in scopus
  • Hit : 266
  • Download : 0
We report laser cladding of pure titanium on a CoCrMo alloy using directed energy deposition. Using electron microscopy, the microstructural evolution upon varying the process parameters, especially laser power and powder feed rate, was investigated in relation to crack formation. Cladding layers showing dilution rates of more than 5% contained cracks due to the formation of the brittle Co2Ti intermetallic phase. The observed cracks could be ascribed to a mismatch in thermal expansion and a resulting stress of more than 440 MPa acting on the Co2Ti phase, as determined by density functional theory and nanoindentation. Furthermore, an excess laser energy caused chemical inhomogeneity and unmelted Ti powder particles, while a deficient laser energy resulted in a lack of fusion. Neither cracks nor partially melted powders were observed for a powder feed rate of 3 g/min and a laser power of 225–300 W, for which the dilution rate was minimized to less than 5%. For such samples, the cladding layers comprised pure α-Ti and a uniform CoTi interface with Co2Ti islands.
Publisher
Elsevier
Issue Date
2022-06
Language
English
Citation

JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY, v.111, no.1, pp.99 - 110

ISSN
1005-0302
DOI
10.1016/j.jmst.2021.09.038
URI
http://hdl.handle.net/10203/290473
Appears in Collection
MS-Journal Papers(저널논문)
Files in This Item
There are no files associated with this item.

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0