Author Affiliations
1School of Materials Science and Engineering, Beihang University, Beijing 100191, China2Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China3Printing Research & Engineering Technology Center, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China4Tianmushan Laboratory (Zhejiang Provincial Laboratory for Aviation), Hangzhou 311115, Zhejiang , Chinashow less
Fig. 1. Two types of additive manufacturing processes mostly used in shape memory alloys (SMAs) forming. (a) L-PBF process principle
[64]; (b) L-PBF process parameters
[65]; (c) L-PBF system
[65]; (d) L-DED process principle
[64]; (e) L-DED process parameters
[66]; (f) L-DED system
[67] Fig. 2. Mechanism of elastocaloric effect of SMAs
[71]. (a) Stress loading accompanies temperature increasing; (b) stress unloading accompanies temperature decreasing
Fig. 3. Elastocaloric performance of additive manufactured elastocaloric materials with excellent refrigeration capacity. (a)‒(b) Laser-directed energy deposited NiTi alloys exhibit quasi-linear superelasticity with less energy dissipation and a large adiabatic temperature drop of -7.5 ℃
[74]; (c) adiabatic temperature drop of NiMnSn materials under an additional applied magnetic field is greater than that under a single stress field because the applied magnetic field stabilizes the austenitic phase and reduces the residual martensite phase after stress unloading
[77]; (d) NiTi alloys with three porous structures fabricated by L-PBF exhibit smaller working driving forces than bulk NiTi alloys of the same size
[78] Fig. 4. Elastocaloric materials with long fatigue life
[66]. (a)‒(b) Compressive stress‒strain curves and elastocaloric effect of Ni
51.5Ti
48.5/Ni
3Ti nanocomposites prepared by L-DED after aging treatment; (c) relationship between ∆
E/
E and fatigue life
Fig. 5. Effects of scanning speeds, scanning spacing, and laser power on phase transition behavior, respectively
[86]. (a)‒(c) Variations in the DSC curves when the scanning speed, scanning spacing, and laser power are changed; (d) linear relationship between each parameter and the peak temperature of martensitic transformation
Fig. 6. Phase transformation temperature of SLM Ni
50.8Ti
49.2 alloy regulated by aging treatment
[88]. (a) Changes in DSC curves after aging treatment for 1 h at different temperatures; (b) evolution in DSC curve after extended aging treatment time at 350 ℃; (c) superelasticity of as-fabricated SLM Ni
50.8Ti
49.2 alloy; (d) good superelasticity at body temperature (37 ℃) obtained after aging treatment at 350 °C for 1 h
Fig. 7. Effect of remelting process on the properties of additively manufactured metal functional materials. (a)‒(b) Effect of remelting of SLM Cu-Al-Ni-Mn alloy interlayers on the microstructure and austenite phase transformation peak temperature
[90]; (c) principle of laser
in-situ heat treatment in L-DED
[91]; (d) NiTi alloy with
in-situ laser heat treatment behaves larger enthalpy of phase transition
[91] Fig. 8. Micro-defects formed during the preparation of NiTi alloys by L-PBF
[99]. (a) Good formation; (b) keyholing; (c) lack of fusion; (d) balling
Fig. 9. Process parameters optimization of laser additive manufactured SMAs. (a) Laser processing diagram
[101], with solid lines indicating parameter areas applicable to different class processes and dashed lines indicating treatment depths. (b)‒(d) Eager‒Tsai model predicts the forming quality
[99,103]: (b) high-density NiTi alloy and NiTiHf alloy fabricated according to the quality distribution map; (c)‒(d) quality distribution maps of Ni
50.8Ti
49.2 and Ni
50.3Ti
29.7Hf
20 alloys, where the contour line means the maximum hatch spacing with unit of μm
Fig. 10. Inverse pole figure (up) and respective pole figure texture (down) of columnar-grained NiTi alloy
[106]. (a) Hatch spacing of 80 μm; (b) hatch spacing of 120 μm; (c) hatch spacing of 180 μm
Fig. 11. In-situ synchrotron XRD was used to characterize the stress-induced martensitic phase transformation of NiTi SMAs
[66]. (a) Changes in XRD diffraction patterns during stress loading‒unloading; (b) volume fraction of the primary phases in the alloy changes with the evolution of stress
Fig. 12. In-situ synchrotron XRD characterization platforms for L-PBF process. (a) Schematic of the in-situ high-speed X-ray imaging and diffraction characterization platform at the 32-ID-B beamline of the APS; (b) schematic of in-situ XRD characterization platform for SSRL 10-2 beamline; (c) schematic of in-situ XRD characterization platform for DESY PETRA III P07 beamline; (d) schematic of in-situ XRD characterization platform for ESRF ID-31 beamline; (e)‒(g) in-situ XRD characterization platforms for SLS MicroXAS and MS beamlines, where (e) is the in-situ L-PBF device mounted at MicroXAS beamline, (f) is the in-situ L-PBF device mounted at MS beamline, and (g) is schematic of the in-situ L-PBF device and diffraction geometry
Fig. 13. Schematics or pictures of in-situ synchrotron XRD characterization platforms for L-DED process. (a)‒(c) Schematics of in-situ XRD characterization platform for DESY PETRA III P07 beamline: (a) in-situ L-DED device picture; (b) picture of the processing head and a build sample; (c) sketch of in-situ L-DED. (d)‒(e) Schematics of in-situ XRD characterization platform for DLS JEEP beamline: (d) schematic of in-situ XRD of the L-DED process; (e) blown powder additive manufacturing process replicator designed to reproduce the operation of a commercial L-DED system. (f)‒(g) schematics of in-situ XRD characterization platform for BSRF 3W1 beamline: (f) schematic of in-situ XRD of the L-DED process; (g) picture of the L-DED device
Fig. 14. In-situ XRD studies on phase transition dynamics during additive manufacturing process. (a)‒(c) Characterization of phase transition dynamics of commercial additively manufactured 17-4 stainless steel (C_17-4) during laser melting
[50]: (a) schematic illustration of
in-situ laser-melting XRD experiment; (b) room temperature XRD pattern of as-solidified C_17-4 after laser melting; (c) XRD intensity map (XRD peak intensity evolution as a function of time) during laser melting of C_17-4 from 0 s to 20 s. (d)
In-
situ XRD characterization on martensitic hot working tool steel during different modes of laser melting process
[49]: the left image shows XRD intensity map of solidification in thin plate melting mode (frame rate: 250 Hz) and the right image shows XRD intensity map of solidification in flat plate melting mode (frame rate: 20000 Hz)
Fig. 15. Texture evolution with repeated laser passes over the seventh layer within a sample manufactured with a laser power of 55 W
[55] Fig. 16. Time series of the representative Laue diffraction patterns during laser remelting processes
[112]. (a)‒(e) Laue diffraction images collected at 0, 225, 250 , 350, and 1000 ms; (f) Local enlarged drawings of the diffraction spots of γ(
) and γ(
) lattice planes at 0 and 1000 ms; (g)‒(h) variation diagrams of γ(113) crystal plane with time in the
χ direction (g) and 2
θ direction (h). The laser was switched on at 150 ms and off at 250 ms
Location | Light source | Beamline | X-ray energy |
---|
United States | Advanced Photon Source (APS) | Beamline 32-ID-B/1-ID-E | 24 keV[40-41]/61.3 keV[49-50] | Germany | Deutsches Elektronen-Synchrotron (DESY) PETRA III | P07 beamline | 79 keV[48], 98.02 keV[55,108], 103.43 keV[54] | United States | Stanford Synchrotron Radiation Lightsource (SSRL) | Beamline 10-2 | 20 keV[42-43] | Europe | European Synchrotron Radiation Facility (ESRF) | Beamline ID-31 | 68.4 keV[47] | Switzerland | Swiss Light Source (SLS) | MicroXAS/ MS beamline | 9.3 keV[45], 12 keV[44], 17.2 keV[49] |
|
Table 1. In-situ synchrotron XRD characterization platforms for L-PBF process
Location | Light source | Beamline | X-ray energy |
---|
Germany | DESY PETRA III | P07-EH3 beamline | 97.6 keV[52-53] | United Kingdom | Diamond Light Source (DLS) | Joint Engineering, Environmental, and Processing (JEEP) beamline | 70 keV[51] | China | Beijing Synchrotron Radiation Facility (BSRF) | 3W1 beamline | High-energy white/monochromatic light [112] |
|
Table 2. In-situ synchrotron XRD characterization platforms for L-DED process