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disconnected and the part has no consolidated shape to be able to take the increasing load. This needs to be verified against the behaviour of the curved layer FDM part. The target displacement to decide on the yielding of the material is 0.2 mm as obtained from an observation of the load displacement diagram obtained from the tensile test on Fabepoxy and shown in Fig. 5.6. The flat layer component seems to have attained the target displacement, suggesting the initiation of plastic flow and subsequent failure of the component at a relatively high overall load, but due to the anomaly stated above, the actual nodal force is much lower, and as already hinted, the components seem to be failing at very early stages of loading. This is attributed to the weak interlayer bonds emanating from the flat layer structure. The curved layer FDM model on the other hand, produced a more meaningful result as expected. As shown in Fig. 5.13, the load pattern was distributed around the region at the top central regions of the part, though there is a concentration of the load around the top partition line, as it was originally applied only at those loads on this line. There is a gradual increase in the load as time passes by, as shown in the figures on the left side of Fig. 5.13. The corresponding vertical deflection diagrams on the right column also show a gradual increase from the top to bottom. Finally, the target displacement of 0.2 mm is attained at some portions at the top, when the overall load is around 500-600 N. This is a bit of an over estimation compared to the experimental result from the three point bending, giving a failure load of around 400 N in general. However, the finite element simulation is not very far from the experimental value, given the lack of accurate property data. Further, the mesostructure with a 25% deformation of each strand is a gross simplification, which in actual practice would be a continuously varying phenomenon. The maximum principal stress in the vertical direction is plotted as shown in Fig. 5.14 for the curved layer FDM part. It is evident that the maximum stress is first reached at the bottom potion of the arch, suggesting the initiation of plastic deformation, crack formation and subsequent tearing apart of the part occurring around this area. The results from the three point bending confirm the same result. Finally, a look at the 116
overall deflection pattern of two specimens under investigation presents a marked difference in the mechanisms of deformation between the two. 117
Page 1 and 2:
An Investigation into curved layer
Page 3 and 4:
Contents Abstract..................
Page 5 and 6:
3.5.2 Fabepoxy.....................
Page 7 and 8:
methodology to print simple curved
Page 9 and 10:
List of Figures 1.1 The Rapid proto
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4.3 Parts being tested with Hounsfi
Page 13 and 14:
List of Abbreviations 3D: Three dim
Page 15 and 16:
Fig 1.1 The Rapid prototyping Cycle
Page 17 and 18:
1.1.1 Stereolithography Stereolitho
Page 19 and 20:
The object to be made is first mode
Page 21 and 22:
1.1.5 Laser Engineered Net Shaping
Page 23 and 24:
1.2 Fused Deposition Modeling A det
Page 25 and 26:
Fig 1.8 Deposition Head Different t
Page 27 and 28:
900mc is capable of producing parts
Page 29 and 30:
noted that the parts built in this
Page 31 and 32:
structure. Honeycomb scaffold archi
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optimal direction to build a part t
Page 35 and 36:
processing treatment was analyzed w
Page 37 and 38:
The actual influence of the curved
Page 39 and 40:
Separating the Main part with its s
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limited to simple models. It could
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Fig 2.2 Faces, Edges and Vertices o
Page 45 and 46:
2.1.5 Constructive Solid Geometry C
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A STL file is a triangular represen
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Fig 2.8 A sample Binary STL File Sl
Page 51 and 52:
Different processes may either vary
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At the very outset of generating th
Page 55 and 56:
and correction of each point to sat
Page 57 and 58:
apid prototyping machine are remove
Page 59 and 60:
Fig 2.13 Main Part Fig 2.14 Support
Page 61 and 62:
As this text file is to be used wit
Page 63 and 64:
mounted to the axes carriage. Timin
Page 65 and 66: Fig 3.1 The deposition head At the
Page 67 and 68: 3.2.3 Assembling Electronics and ca
Page 69 and 70: microcontroller is now disconnected
Page 71 and 72: The relationship between test point
Page 73 and 74: on the mechanical properties and po
Page 75 and 76: 3.5.1 Silicone with other materials
Page 77 and 78: Fab@home machine. Since our require
Page 79 and 80: are printed using the two suitable
Page 81 and 82: The support structure‟s dimension
Page 83 and 84: machine Fig 3.13 Flat and curved la
Page 85 and 86: 4.1 Experimental conditions Chapter
Page 87 and 88: have many factors from contention a
Page 89 and 90: 4.3 Taguchi methods There are two t
Page 91 and 92: Such steps usually identify the nee
Page 93 and 94: Nominal is best Larger is better S
Page 95 and 96: Control of material flow - The lead
Page 97 and 98: Fig 4.3 Parts being tested with Hou
Page 99 and 100: values in all cases are almost doub
Page 101 and 102: level. The other parameters were in
Page 103 and 104: The finite element method has had a
Page 105 and 106: performance of finished FDM parts [
Page 107 and 108: ehaviour with failure occurring at
Page 109 and 110: Fig. 2 (a) is the thin curved part
Page 111 and 112: Table 5.1 Property data: Fabepoxy M
Page 113 and 114: optimum number. The final finite el
Page 115: Fig. 5.11 Load and boundary conditi
Page 119 and 120: Fig. 5.13 Variation of compressive
Page 121 and 122: Fig. 5.15 shows the overall deforma
Page 123 and 124: The effectiveness of the deposition
Page 125 and 126: [11] M. Greul, T. Pintat, M. Greuli
Page 127 and 128: [32] Philip J. Ross, 1988, “Taguc
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