Process capability analysis of binder jetting 3D printing process for fabrication of calcium sulphate based porous bone scaffolds.

This study aims at investigating the process capability of a 3D printer for the fabrication of porous bone scaffolds. Initially, a suitable material is identified by optimising process parameters of a 3D printer using a full factorial design approach. Then, dimensional deviation and tolerance grades of the scaffold samples are calculated. Finally, process capability indices are evaluated and the process is recentred. Out of two materials under study, VisiJet PXL Core powder is found to provide better dimensional accuracy. Tolerance grades of the samples are found to be ranged from IT3 to IT10. Maximum dimensional deviation before and after centring the process is found to be 0.47% and 0.44%, respectively. Process capability indices C-p and C-pk are greater than 1 and close to industry benchmark (C-pk >= 1.33). This indicates the process is under statistical control and capable of fabricating porous bone scaffolds suitable for in vitro or in vivo bone tissue engineering applications.