Free-form fabrication

Cima LG, Cima MJ (1996) Tissue regeneration matrices by solid free form fabrication techniques. US Patent 5518680... 

Various fabrication methods have been developed in order to attain the 3D scaffold characteristics. In the case of synthetic polymer or polymer-matrix composite scaffolds, the methods include [47] solvent casting and particle leaching, phase separation, extrusion, gas foaming, and free form fabrication. Each method presents certain advantages with respect to others, ranging from ease of manufacture to control of the microstructure/nanostructure. Solvent casting and phase separation methods have been studied at our laboratory. 

First, a 3D stmcture is designed using CAD software. Data obtained from computerized tomography (CT) or magnetic resonance imaging (MRI) medical scans can be used to create a customized CAD model. This CAD model is then expressed in a series of cross-sectional layers. The complex scaffold architecture must be built using layer-by-layer (LBL) manufacturing processes known collectively as solid free-form fabrication (SFF). 

J.M. Tian, Y. Zhang, X.M. Guo, L.M. Dong, Preparation and characterization of hydroxyapatite suspensions for solid free form fabrication, Ceram Int., 28, 299-302 (2002). 

Z. S. Liu, S. Z. Erhan and P. D. Calvert, Sohd free form fabrication of soybean oil based composites reinforced with clay and fibers . J Am Oil Chem Soc, 2004, 81, 605-10. 

The selective laser sintering (SLS) process is also known as laser powder deposition (24). Laser deposition is a solid free-form fabrication method. There, a laser beam is used to melt an addition material to create a material track with approximately hemispherical cross section. 

Solid free form fabrication (SFF) Fusion deposition modeling 3D printed parts... 

Figure 6.49 Basic principle of solid free-form fabrication.

Moist granular ceramics produced by the common forming methods such as tape casting and extrusion must be dried prior to binder burnout and sintering. Drying is also a key step in solid free-form fabrication techniques that involve laya--by-layer deposition of colloidal suspensions. 

In this chapter we considered the common ceramic forming methods and briefly described the solid free-form fabrication routes applicable to ceramics. Powder consolidation forms the last major processing step prior to the sintering process in which the microstructure of the final article is developed. Heterogeneities present in the green body cannot be easily removed during sintering, so control of... 

Lee JW, Kim JY, Cho DW. Sohd free-form fabrication technology and its apphcation to hone tissue engineering. Int J Stem Cells 2010 3 85-95. 

Calvert, P, and Crockett, R. (1997). Chemical solid free-form fabrication making shapes without molds, Chem. Mater. 9,650-663. 

Wu B M, Borland S W, Giordano R A, Cima L G, Sachs E M and Cima M J, Solid free-form fabrication of drug delivery devices , J. Controlled Release, 1996,40,77-87. 

Schek, R. M., Taboas, J. M., Segvich, S. J., Hollister, S. J., Krebsbach, P. H. 2004. Engineered osteochondral grafts using biphasic composite solid free-form fabricated scaffolds. Tissue Eng 10(9-10) 1376-85. 

Taboas J, Maddox R, Krebsbach P, Hollister S. Indirect solid free form fabrication of local and global porous, biomimetic and composite 3D polymer-ceramic scaffolds. Biomaterials 2003 24 181-94. 

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