Chinese Journal of Lasers, Volume. 51, Issue 20, 2002308(2024)
Effects of SLM Process and Cyclic Heat Treatment on Microstructure and Hardness of Mn-30%Cu Alloy
Figures & Tables(22)
Fig. 1. Scanning electron microscope photographs of powder raw material. (a) Mn powder; (b) Cu powder; (c) mix powder
Fig. 2. Relative density of SLM formed Mn-30%Cu alloy sample versus scanning speed with optical microscope images at scanning speeds of 300, 400, and 500 mm·s-1 shown in inset
Fig. 3. XRD patterns of samples. (a) XRD patterns at different SLM scanning speeds; (b) partial enlargement of Fig.3(a); (c) comparison of XRD patterns before and after CHT; (d) partial enlargement of Fig.3(c)
Fig. 4. Microstructures of SLMed Mn-30%Cu alloys in XOY plane at different SLM scanning speeds. (a) 300 mm/s; (b) 400 mm/s; (c) 500 mm/s; (d) 600 mm/s; (e) 700 mm/s
Fig. 5. Microstructures of SLMed Mn-30%Cu alloys in YOZ plane at different SLM scanning speeds. (a) 300 mm/s; (b) 400 mm/s; (c) 500 mm/s; (d) 600 mm/s; (e) 700 mm/s
Fig. 6. Widths of scanning tracks and molten pools of Mn-30%Cu alloys formed at different SLM scanning speeds
Fig. 7. Micrographs of Mn-30%Cu alloy formed by SLM in XOY plane. (a) Whole; (b) scanning track edge; (c) scanning track center
Fig. 8. Micrographs of Mn-30%Cu alloy formed by SLM in YOZ plane. (a) Whole; (b) molten pool edge; (c) molten pool center
Fig. 9. Grain sizes at different locations and SEM image. (a) Grain sizes at different locations under different SLM scanning speeds; (b) SEM image
Fig. 10. Microscopic images of SLMed+CHTed samples. Optical micrographs at scanning speeds of (a1) 300, (b1) 400, (c1) 500,(d1) 600, and (e1) 700 mm/s; (a2) (b2) (c2) (d2) (e2) corresponding electron microscope images of small grains; (a3) (b3) (c3) (d3) (e3) corresponding electron microscope images of large grains; (f) boundary between large and small grains
Fig. 11. Grain size in Mn-30%Cu alloy versus SLM scanning speed after CHT. (a) Large grain; (b) small grain
Fig. 12. EBSD results of Mn-30%Cu alloy sample held at 900 ℃ for 1 h.(a) Grain orientation distribution; (b) proportion of grain orientation
Fig. 13. Mass fraction and burning ratio of Mn in Mn-30%Cu alloy formed by SLM versus scanning speed
Fig. 14. Microhardness values of SLMed and SLMed+CHTed Mn-30%Cu alloys versus scanning speed
Fig. 15. Microhardness values of large grains and small grains in SLMed+CHTed Mn-30%Cu alloy
Table 1. Size distributions of manganese powder and copper powder
View tableTable 1. Size distributions of manganese powder and copper powder
Powder Manganese Copper D10 /μm 6.2 16.1 D50 /μm 22.1 34.9 D90 /μm 53.3 65.5
Table 2. SLM process parameters
View tableTable 2. SLM process parameters
Parameter Value Laser power P /W 196 Scanning speed V /（mm/s） 300， 400， 500， 600， 700 Hatching distance D /mm 0.06 Layer thickness δ /mm 0.02 Phase angle /（°） 90 Spot diameter d /μm 100 Laser wavelength λ /nm 1060
Table 3. Relative density values of SLMed and SLMed+CHTed Mn-30%Cu samples at different scanning speeds
View tableTable 3. Relative density values of SLMed and SLMed+CHTed Mn-30%Cu samples at different scanning speeds
Scanning speed /（mm/s） 300 400 500 600 700 Relative density /% ~98.30 ~99.48 ~99.75 ~99.72 ~99.42
Table 4. Mn burning ratios of SLMed and SLMed+CHTed Mn-30%Cu samples at different scanning speeds
View tableTable 4. Mn burning ratios of SLMed and SLMed+CHTed Mn-30%Cu samples at different scanning speeds
Scanning speed /（mm/s） 300 400 500 600 700 Mn burning ratio/% 20.7 17.6 10.4 9.4 8.1
Table 5. Grain sizes of Mn-30%Cu samples at different scanning speeds
View tableTable 5. Grain sizes of Mn-30%Cu samples at different scanning speeds
Scanning speed /（mm/s） 300 400 500 600 700 Grain size of SLMed sample at molten pool edge 1.41 1.36 1.29 1.20 1.36 Grain size of SLMed sample in molten pool center 0.93 0.82 0.79 0.75 0.88 Grain size of SLMed+CHTed sample at molten pool edge 4.5 3.7 3.2 2.6 2.8 Grain size of SLMed+CHTed sample in molten pool center 194 172 160 170 206
Table 6. Phase compositions of Mn-30%Cu samples at different scanning speeds
View tableTable 6. Phase compositions of Mn-30%Cu samples at different scanning speeds
Scanning speed /（mm/s） 300 400 500 600 700 Phase composition of SLMed sample γ-（Mn，Cu） Phase composition of SLMed+CHTed sample γ-（Mn，Cu）with a small amount of α-Mn and γ′-（Mn，Cu）
Table 7. Microhardness values of Mn-30%Cu samples at different scanning speeds
View tableTable 7. Microhardness values of Mn-30%Cu samples at different scanning speeds
Scanning speed /（mm/s） 300 400 500 600 700 Microhardness of SLMed sample 145.1 143.0 149.3 153.2 146.1 Microhardness of SLMed+CHTed sample 143.1 137.1 144.9 144.4 141.3
Tools
Get Citation
Copy Citation Text
Yihui Zhang, Tongbo Wei, Chenyu Su, Jingjing Yang, Zemin Wang. Effects of SLM Process and Cyclic Heat Treatment on Microstructure and Hardness of Mn-30%Cu Alloy[J]. Chinese Journal of Lasers, 2024, 51(20): 2002308
Paper Information
Category: Laser Additive Manufacturing
Received: Dec. 11, 2023
Accepted: Apr. 2, 2024
Published Online: Oct. 14, 2024
The Author Email: Yang Jingjing (jjyang0803@whu.edu.cn)
CSTR:32183.14.CJL231497
© Copyright 2018-2021 | Chinese Laser Press.
All Rights Reserved 沪ICP备15018463号-20