Effect of Different Heat Treatments on Microstructure, Properties, and Anisotropy of SLM TC4

Zhen Dou; Yuyue Wang; Anfeng Zhang; Mengjie Wu; Puqiang Wang

doi:10.3788/CJL202149.0802009

Journals >Chinese Journal of Lasers >Volume 49 >Issue 8 >Page 0802009 > Article

Chinese Journal of Lasers
Vol. 49, Issue 8, 0802009 (2022)

Effect of Different Heat Treatments on Microstructure, Properties, and Anisotropy of SLM TC4

Zhen Dou¹, Yuyue Wang¹, Anfeng Zhang^2、*, Mengjie Wu², and Puqiang Wang¹

Author Affiliations

¹State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China

²State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710054, Shaanxi, China

show less

DOI: 10.3788/CJL202149.0802009 Cite this Article Set citation alerts

Zhen Dou, Yuyue Wang, Anfeng Zhang, Mengjie Wu, Puqiang Wang. Effect of Different Heat Treatments on Microstructure, Properties, and Anisotropy of SLM TC4[J]. Chinese Journal of Lasers, 2022, 49(8): 0802009 Copy Citation Text

show less

Schematic diagram of SLM TC4 sample forming method and size. (a) Schematic of horizontal specimen；(b) schematic of vertical specimen; (c) physical drawing of horizontal forming; (d) physical drawing of vertical forming

Fig. 1. Schematic diagram of SLM TC4 sample forming method and size. (a) Schematic of horizontal specimen；(b) schematic of vertical specimen; (c) physical drawing of horizontal forming; (d) physical drawing of vertical forming

Download full size

Fig. 2. Macro morphology of SLM TC4. (a) SLM-V; (b) SLM-H

Download full size

Fig. 3. Images of low-magnification microstructure of SLM TC4 deposited state and different heat treatment processes. (a) As-deposited; (b) HM1; (c) HM2; (d) HM3

Download full size

Fig. 4. SEM images of low-magnification microstructure of SLM TC4 deposited state and different heat treatment processes. (a) As-deposited; (b) HM1; (c) HM2; (d) HM3

Download full size

Fig. 5. Anisotropic histogram of microstructure in deposited state and different heat treatment processes

Download full size

Fig. 6. Tensile stress state of grain boundaries in different directions and crack propagation path diagram. (a) SLM-H；(b) SLM-V; (c) schematic diagram of crack propagation pathin deposited state and after heat treatment

Download full size

$Tensile fracture morphology of SLM TC4 in deposited state. (a) SLM-H(×80); (b) SLM-H(×2000); (c) SLM-H(×5000); (d) SLM-V (×80); (e) SLM-V(×2000); (f) SLM-V(×5000)$

Fig. 7. Tensile fracture morphology of SLM TC4 in deposited state. (a) SLM-H(×80); (b) SLM-H(×2000); (c) SLM-H(×5000); (d) SLM-V (×80); (e) SLM-V(×2000); (f) SLM-V(×5000)

Download full size

$Topography of the tensile fracture of different heat treatment processes. (a) HM1-H(×80); (b) HM1-H(×2000); (c) HM1-V(×80); (d) HM1-V(×2000); (e) HM2-H(×80); (f) HM2-H(×2000); (g) HM2-V(×80); (h) HM2-V(×2000); (i) HM3-H(×80); (j) HM3-H(×2000); (k) HM3-V(×80); (l) HM3-V(×2000)$

Fig. 8. Topography of the tensile fracture of different heat treatment processes. (a) HM1-H(×80); (b) HM1-H(×2000); (c) HM1-V(×80); (d) HM1-V(×2000); (e) HM2-H(×80); (f) HM2-H(×2000); (g) HM2-V(×80); (h) HM2-V(×2000); (i) HM3-H(×80); (j) HM3-H(×2000); (k) HM3-V(×80); (l) HM3-V(×2000)

Download full size

Element	Al	V	Fe	C	N	H	O	Ti
Mass fraction /%	6.01	3.92	0.164	0.005	0.002	0.001	0.072	Bal.

Table 1. Chemical composition of TC4 powder

No.	Heat treatment processes
SLM	As-built
HM1	TC4 samples are first air cooled after solution treatment at 950 ℃ for 1 h, and then air is cooled after aging at 550 ℃ for 4 h.
HM2	TC4 samples are heated to 920 ℃ for 5 min, then cooled to 700 ℃ for 10 min in the furnace, which is repeated five times and then samples are air cooled.
HM3	TC4 samples are kept at 920 ℃ for 10 min, cooled slowly to 800 ℃ and kept for 30 min in the furnace. When the temperature is 550 ℃，samples are immediately heated to 920 ℃. The whole process is repeated for 4 times and then samples are cooled in the furnace. At last the solution heat treating is performed at 920 ℃ for 1 h and aging treatment is performed at 550 ℃ for 4 h.

Table 2. Heat treatment processes of SLM TC4 alloy

Treatment	Tensile direction	Ultimate tensile strength σ_b/MPa	Yield strength σ_s/MPa	Elongation /%	Rate of reduction in area /%
SLM	H	1226.0±19.54	1048.2±19.15	13.1±1.16	42.6±1.85
SLM	V	1220.0±8.08	1060.2±8.21	11.5±1.82	40.2±2.32
HM1	H	952.4±3.61	862.4±3.26	17.5±1.79	49.2±1.17
HM1	V	963.4±3.38	868.4±7.00	17.7±1.21	48.8±1.94
HM2	H	883.8±4.92	792.2±6.31	18.8±1.54	45.4±1.02
HM2	V	893.4±7.94	807.6±8.21	17.4±1.56	48.0±1.41
HM3	H	936.6±4.84	848.6±3.26	19.1±1.77	47.0±2.97
HM3	V	955.8±4.71	865.6±2.94	17.6±2.27	48.4±1.02
GB/T 25137-2010		895	828	10.0	25.0

Table 3. Mechanical properties of SLM TC4 alloy tensile specimens under different treatment conditions

Download Citation

Set citation alerts for the article

Tools

Set citation alerts for the article

Save the article for my favorites

Paper Information