Details
| Original language | English |
|---|---|
| Article number | 115911 |
| Journal | Engineering structures |
| Volume | 284 |
| Early online date | 17 Mar 2023 |
| Publication status | Published - 1 Jun 2023 |
Abstract
In this study, a directed energy deposition (DED) process called wire arc additive manufacturing (WAAM) is employed for the fatigue strengthening of damaged steel members. Three steel specimens with central cracks were tested under a high-cycle fatigue loading (HCF) regime: (1) the reference specimen; (2) the WAAM-repaired specimen with an as-deposited profile, and (3) the WAAM-repaired specimen machined to reduce stress concentration factors (SCF). The corresponding finite element (FE) simulation of the WAAM process was calibrated using static experimental results, which revealed the main mechanism. The process was found to introduce compressive residual stresses at the crack tip owing to the thermal contraction of the repair. The FE results also revealed that stress concentration exists at the root of the as-deposited WAAM; this stress concentration can be mitigated by machining the WAAM to a pyramid-like shape. The fractography analysis indicated that the cracks were initiated at the WAAM-steel interface, and microscopic observations revealed that the microcracks were arrested by the porosities in the melted interface. The results of this pioneering study suggest that WAAM repair is a promising technique for combating fatigue damage in steel structures.
Keywords
- Crack arrest, Fatigue life extension, Fatigue repair, Hybrid manufacturing, Metal 3D-printing
ASJC Scopus subject areas
- Engineering(all)
- Civil and Structural Engineering
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In: Engineering structures, Vol. 284, 115911, 01.06.2023.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Fatigue strengthening of damaged steel members using wire arc additive manufacturing
AU - Ghafoori, E.
AU - Dahaghin, H.
AU - Diao, C.
AU - Pichler, N.
AU - Li, L.
AU - Mohri, M.
AU - Ding, J.
AU - Ganguly, S.
AU - Williams, S.
N1 - Funding Information: The first author acknowledges the support for this study (project number IZSEZ0_202441) provided by the Swiss National Science Foundation (SNSF) .
PY - 2023/6/1
Y1 - 2023/6/1
N2 - In this study, a directed energy deposition (DED) process called wire arc additive manufacturing (WAAM) is employed for the fatigue strengthening of damaged steel members. Three steel specimens with central cracks were tested under a high-cycle fatigue loading (HCF) regime: (1) the reference specimen; (2) the WAAM-repaired specimen with an as-deposited profile, and (3) the WAAM-repaired specimen machined to reduce stress concentration factors (SCF). The corresponding finite element (FE) simulation of the WAAM process was calibrated using static experimental results, which revealed the main mechanism. The process was found to introduce compressive residual stresses at the crack tip owing to the thermal contraction of the repair. The FE results also revealed that stress concentration exists at the root of the as-deposited WAAM; this stress concentration can be mitigated by machining the WAAM to a pyramid-like shape. The fractography analysis indicated that the cracks were initiated at the WAAM-steel interface, and microscopic observations revealed that the microcracks were arrested by the porosities in the melted interface. The results of this pioneering study suggest that WAAM repair is a promising technique for combating fatigue damage in steel structures.
AB - In this study, a directed energy deposition (DED) process called wire arc additive manufacturing (WAAM) is employed for the fatigue strengthening of damaged steel members. Three steel specimens with central cracks were tested under a high-cycle fatigue loading (HCF) regime: (1) the reference specimen; (2) the WAAM-repaired specimen with an as-deposited profile, and (3) the WAAM-repaired specimen machined to reduce stress concentration factors (SCF). The corresponding finite element (FE) simulation of the WAAM process was calibrated using static experimental results, which revealed the main mechanism. The process was found to introduce compressive residual stresses at the crack tip owing to the thermal contraction of the repair. The FE results also revealed that stress concentration exists at the root of the as-deposited WAAM; this stress concentration can be mitigated by machining the WAAM to a pyramid-like shape. The fractography analysis indicated that the cracks were initiated at the WAAM-steel interface, and microscopic observations revealed that the microcracks were arrested by the porosities in the melted interface. The results of this pioneering study suggest that WAAM repair is a promising technique for combating fatigue damage in steel structures.
KW - Crack arrest
KW - Fatigue life extension
KW - Fatigue repair
KW - Hybrid manufacturing
KW - Metal 3D-printing
UR - http://www.scopus.com/inward/record.url?scp=85150302475&partnerID=8YFLogxK
U2 - 10.1016/j.engstruct.2023.115911
DO - 10.1016/j.engstruct.2023.115911
M3 - Article
AN - SCOPUS:85150302475
VL - 284
JO - Engineering structures
JF - Engineering structures
SN - 0141-0296
M1 - 115911
ER -