Multi-material 3D Printing Technique For Fabricating Organ Model

Medical model has been widely applied in medical field,such as serving as implant,surgical planning and medical education.The traditional way to produce the medical model is by means of manual sculpture,which is time-consuming and the model's quality highly relies on the skill level of the sculpturer.With the rapid evolution of medical imaging technology such as CT and MRI,high-resolution 3D image data can be acquired within a single breath-hold.With the help of 3D printing techniques,graspable 3D medical model can be produced.However most medical models based on 3D printing are still made out of one single material,which can't reflect multi-component nature of the real organ.In this thesis,we made use of multi-material 3D printing techniques to fabricate medical model.A 3D printing platform with an extrusion system based on FDM techniques was developed for hybrid printing of ABS and TPU.And we researched from experimental and theoretical aspects on how to improve the mechanical performance,especially bond strength of multi-FDM parts.Regarding the experiment aspects,we investigated on the effect of printing parameters on material printability,temperature history and bond strength.As for the theoretical aspect,We developed a thermal-driven printing fiber diffusion-bonding theory,and combined with temperature field simulation of the multi-material FDM process,we demonstrated the formation of bond strength and the effect of printing parameters on the bond strength,which offered the guideline for how to enhance the strength of multi-material printed parts.In the last,we demonstrated the process of applying multi-FDM techniques to fabricate organ model with a case of forearm phantom production,and by quantitative characterizing of the mechanical performance of the forearm phantom,we demonstrated we could fabricate tissue-like organ model with this techniques.