Research Progress on Powder-based Laser Additive Manufacturing Technology of Ceramics

doi:10.15541/jim20210590

Abstract

Abstract:

Ceramics, with its excellent thermal, physical and chemical properties, have great potential applications in various fields, such as aerospace, energy, environmental protection and bio-medicine. With the development of relevant technology in these fields, the structural design of core components is increasingly complex, and the internal microstructures gradually become customized and gradient. However, the hard and brittle features of ceramics make it difficult to realize the forming of special-shaped parts by traditional manufacturing methods, which in turn limits further application. As a rapidly developing additive manufacturing technology, laser additive manufacturing technology presents a momentous advantage in the manufacturing process of extremely precision ceramic components: free molding without mold and support, quick response feature and short developing cycle, etc. At the same time, the technology can realize the flexible deployment of ceramic parts, which is expected to solve the problems mentioned above. Three kinds of powder-based laser additive manufacturing techniques of ceramic were reviewed in this paper: selective laser sintering and selective laser melting based on powder bed fusion technology; laser engineered net shaping based on direct energy deposition technology. The forming principle and characteristics were mainly discussed; the research progress of ceramic green body densification process in selective laser sintering technology and the forming principle, propagation mechanism and control methods of ceramic green body cracks in selective laser melting, and laser engineered net shaping technology were reviewed; the technical characteristics of selective laser sintering, selective laser melting and laser engineered net shaping technologies in shaping of ceramic parts were compared and analyzed; and the future development trends of laser additive manufacturing technology of ceramic parts were prospected.

Key words: laser additive manufacturing, selective laser sintering, selective laser melting, laser engineered net shaping, ceramic, review

CLC Number:

TQ174

CAO Jiwei, WANG Pei, LIU Zhiyuan, LIU Changyong, WU Jiamin, CHEN Zhangwei. Research Progress on Powder-based Laser Additive Manufacturing Technology of Ceramics[J]. Journal of Inorganic Materials, 2022, 37(3): 241-254.

Figures/Tables 15

Fig. 1 Schematic diagram of selective laser sintering (SLS) technology[1]

Fig. 2 Process of SLS and its post-treatment process for ceramic[1] The process marked with asterisk * is optional. SLS: Selective laser sintering

Fig. 3 ZrO2 ceramic parts and their morphologies prepared by SLS combined with isostatic pressing[28] (a, d) ZrO2 ceramic green bodies and their morphologies printed by SLS; (b) Warm isostatic pressure equipment; (c, e) ZrO2 ceramics and their microstructures after warm isostatic pressing sintering. SLS: Selective laser sintering; WIP: Warm isostatic pressing

Fig. 4 Preparation process of SiC ceramics and its composite parts by SLS[33,36-37] (a-d) Reaction sintering of Cf/SiC ceramic matrix composites by SLS technology; (e-h) SLS preparation process of SiC/SiC ceramics PF: Phenolic resin; Cf: Carbon fiber; SLS: Selective laser sintering; LSI: Liquid silicon infiltration; PIP: Precusor infiltration pyrolysis

Fig. 5 Methods of porous ceramic by SLS technology[38,39,40,41] (a) Pre-treatment of ceramic particles and SLS; (b) Sintering of porous ceramic;(c) Porous mullite ceramic; (d) Porous Al2O3 ceramic; (e) Porous Si3N4 ceramic; SLS: Selective laser sintering

Fig. 6 Application of porous ceramic by SLS technology in biomedicine (a, b) CC-PLLA porous skull scaffolds and their mechanical properties[43]; (c, d) Porous biological ceramic scaffolds and their micromorphologies[48] SLS: Selective laser sintering

Fig. 7 Schematic diagram of selective laser melting (SLM) technology[1]

Fig. 8 Ceramics and their microdefects printed by selective laser melting[51,52] (a) ZrO2 sample; (b, c) Al2O3 samples and cracks; (d) Un-melted alumina balls

Fig. 9 Formation of closed pores and pits of ceramic by SLM[54] (a) SLM printing process and Al2O3/GdAlO3/ZrO2 ternary eutectic ceramics; (b) Formation process of the closed pores and pits

Fig. 10 Schematic diagram of laser engineered net shaping (LENS) technology[62,63]

Fig. 11 Ceramic printed by LENS[62,67] (a) Al2O3 spherical particles; (b, c) Large-sized cylindrical Al2O3 ceramic, stress-strain curve and fracture morphology of Al2O3 ceramic; (d) Single-bead wall part fabricated with different laser power; (e) Typical geometry of the cross-section of a single-bead wall part

Fig. 12 Al2O3/GdAlO3/ZrO2 eutectic ceramics[70] (a) Ceramic shaping process; (b) Eutectic ceramic sample; (c) Annealed eutectic ceramic sample

Fig. 13 CO2 laser preheating method, induction preheating method and prepared ceramics (a) CO2 laser preheating method and ZrO2/Al2O3 ceramic prepared by SLM[77]; (b) Induction preheating method and ZrO2/Al2O3 ceramic prepared by LENS[75]

Fig. 14 Effect of scanning strategy and ultrasonic vibration on the crack defects[63,78] (a) Scanning strategy; (b) Ultrasonic vibration

Table 1 Comparation of powder-based laser additive manufacturing technologies of ceramics

Technology		Raw materials	Post-treatment	Dimensional accuracy	Ref.
PBF	SLS	Al₂O₃, ZrO₂, Si₃N₄, SiC, Cf/SiC, Si₃N_4-SiC/SiO₂, mullite, porous bio-ceramics such as PA-PEEK, HA-PC, CC-PLLA, etc.	Debinding, isostatic pressing/infiltration pyrolysis, pressureless sintering/reactive sintering	High	[28-29, 33-41, 43, 48, 79-80]
PBF	SLM	Al₂O₃, ZrO₂, ZrO₂/Al₂O₃, MoSi₂-Si₃N₄, ZrB₂/ZrC, Al₂O₃-based eutectic ceramics	None	Low	[40, 51-52, 54, 77, 81-83]
DED	LENS	Al₂O₃, ZrO₂/Al₂O₃, Al₂O₃-based eutectic ceramics	None	Low	[59, 63-64, 66, 68-71, 78]

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