While repairing parts using direct energy deposition (DED), defects, such as pores and cracks, can occur at the interface between the substrate and the area to be repaired. Such interfacial defects are due to the thermal stress induced by the temperature gradient resulting from repeated melting and solidification cycles during the powder deposition by laser. These cracks deteriorate the mechanical properties of the repaired parts. This study reports on the suppression of cracks formed at the interface of parts repaired using DED. To this end, excess deposition was introduced such that the deposition volume is greater than the volume to be repaired, to cool down slowly. The excess deposition was performed by varying the width and height of the repairing volume. The experimental results showed the formation of macro-scale cracks in the absence of excess deposition, whereas only micro-scale cracks (10 μm or less) were observed in the repaired sample with a low repair depth in the presence of excess deposition. The cooling rate decreased with the increase in the excess deposition height for the same volume; this is believed to have helped suppress the cracks formed at the interface. With the increase in the height and width of excess deposition, no hardness variations were observed in the deposited layer; however, the hardness values of the substrate tended to decrease. The tensile strength and elongation of the specimen repaired with excess deposition increased by 112 and 175%, respectively, compared with those of the specimen repaired without excess deposition.
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Reimann M, Goebel J, dos Santos JF (2017) Microstructure and mechanical properties of keyhole repair welds in AA 7075-T651 using refill friction stir spot welding. Mater Des 132:283–294
Mirzadeh Rahni MR, Beidokhti B, Haddad-Sabzevar M (2017) Effect of filler metal on microstructure and mechanical properties of manganese−aluminum bronze repair welds. Trans Nonferrous Met Soc China 27:507–513
Enrique PD, Jiao Z, Zhou NY, Toyserkani E (2018) Effect of microstructure on tensile properties of electrospark deposition repaired Ni-superalloy. Mater Sci Eng A 729:268–275
Tan JC, Looney L, Hashmi MSJ (1999) Component repair using HVOF thermal spraying. J Mater Sci Process Technol 92:203–208
Lin X, Cao Y, Wu X, Yang H, Chen J, Huang W (2012) Microstructure and mechanical properties of laser forming repaired 17-4PH stainless steel. Mater Sci Eng A 553:80–88
Zhuang Z, Jing C, Hua T, Xiaolin Z, Weidong H (2017) Microstructure and mechanical properties of laser repaired TC4 titanium alloy. Rare Met Mater Eng 46:1792–1797
Liu Q, Wang Y, Zheng H, Tang K, Li H, Gong S (2016) TC17 titanium alloy laser melting deposition repair process and properties. Opt Laser Technol 82:1–9
Chew Y, Pang JHL, Bi G, Song B (2015) Thermo-mechanical model for simulating laser cladding induced residual stresses with single and multiple clad beads. J Mater Process Technol 224:89–101
Krzyzanowski M, Bajda S, Liu Y, Triantaphyllou A, Rainforth WM, Glendenning M (2016) 3D analysis of thermal and stress evolution during laser cladding of bioactive glass coatings. J Mech Behav Biomed Mater 59:404–417
Wang D, Hu Q, Zeng X (2015) Residual stress and cracking behaviors of Cr13Ni5Si2 based composite coatings prepared by laser-induction hybrid cladding. Surf Coat Technol 274:51–59
Lee C, Park H, Yoo J, Lee C, Woo W, Park S (2015) Residual stress and crack initiation in laser clad composite layer with Co-based alloy and WC + NiCr. Appl Surf Sci 345:286–294
Gong H, Rafi K, Gu H, Starr T, Stucker B (2014) Analysis of defect generation in Ti–6Al–4V parts made using powder bed fusion additive manufacturing processes. Addit Manu 1:87–98
Xiang Y, Zhang S, Wei Z, Li J, Wei P, Chen Z, Jiang L (2018) Forming and defect analysis for single track scanning in selective laser melting of Ti6Al4V. Appl Phy A 124(10):685
Wang F, Mao H, Zhang D, Zhao X, Shen Y (2008) Online study of cracks during laser cladding process based on acoustic emission technique and finite element analysis. Appl Surf Sci 255(5):3267–3275
Hidouci A, Pelletier JM, Ducoin F, Dezert D, El Guerjouma R (2000) Microstructural and mechanical characteristics of laser coatings. Surf Coat Technol 123:17–23
Baek GY, Lee KY, Park SH, Shim DS (2017) Effects of substrate preheating during direct energy deposition on microstructure, hardness, tensile strength, and notch toughness. Met Mater Int 23:1204–1215
Wang F, Mao H, Zhang D, Zhao X (2009) The crack control during laser cladding by adding the stainless steel net in the coating. Appl Surf Sci 255:8846–8854
Fu F, Zhang Y, Chang G, Dai J (2016) Analysis on the physical mechanism of laser cladding crack and its influence factors. Optik 127:200–202
Yoo YG, Kang NH, Kim CH, Kim JH, Kim MS (2007) Effect of process parameters on laser overlay behavior of Fe-based alloy powder on aluminum substrate. J Welding Joining 25:30–36
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Oh, W.J., Son, J.Y., Baek, G.Y. et al. Excess deposition for suppressing interfacial defects induced on parts repaired using direct energy deposition. Int J Adv Manuf Technol 106, 1303–1316 (2020) doi:10.1007/s00170-019-04650-w
- Direct energy deposition (DED)
- Excess deposition
- Tensile test