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Polypropylene composites were prepared from sugarcane bagasse fibers by extrusion and injection molding. Wood flour was used as reference filler in the study. The fiber content of the composites changed between 0 and 30 wt% in 5 wt% steps. Maleated polypropylene was used as coupling agent to improve interfacial adhesion. Mechanical properties were characterized by tensile and fracture testing, while local

Active filler pyrolysis of polymethylsiloxane/aluminum (PMS/Al) mixtures leads to the formation of mullite at 1400°C, and by 1700°C mullite is the only crystalline phase in an amorphous matrix. These mixtures show a complex series of oxidation and reduction reactions prior to the formation of mullite. Initial oxidation of PMS at low temperatures results in the formation of an amorphous product before any significant oxidation of the Al. After melting of the Al phase, redox reactions lead to the formation of elemental Si and SiC as intermediate crystalline phases along with Al2O3 both as the crystalline α‐phase and dissolved in the amorphous matrix. Mullite formation occurs by precipitation from the matrix at temperatures above 1400°C. In contrast, PMS/Al2O3 mixtures did not show mullite formation until heat treatment at 1700°C. In this case no significant intermediate crystalline phases occur, except for some limited cristobalite crystallization from the matrix.

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Abstract. There are several parameters that must be set before manufacturing a product using 3D printing. These parameters include the orientation deposition of that product, type of material, form fill, fill density, and other parameters. The finished product of 3D printing has some responses that can be observed, measured, and tested. Some of those responses are the processing time, the dimensions of the end product, its surface roughness and the mechanical properties, i.e. its yield strength, ultimate tensile strength, and impact resistance. This research was conducted to study the relationship between process parameters of 3D printing machine using a technology of fused deposition modeling (FDM) and the generated responses. The material used was ABS plastic that was commonly used in the industry. Understanding the relationship between the parameters and the responses thus the resulting product can be manufactured to meet the user needs. Three different orientations in depositing the ABS polymer named XY( first orientation), YX (second orientation), and ZX (third orientation) were studied. Processing time, dimensional accuracy, and the product strength were the responses that were measured and tested. The study reports that the printing process with third orientation was the fastest printing process with the processing time 2432 seconds followed by orientation 1 and 2 with a processing time of 2688 and 2780 seconds respectively. Dimension accuracy was also measured from the width and the length of gauge area of tensile test specimens printed in comparison with the dimensions required by ASTM 638-02. It was found that the smallest difference was in thickness dimension, i.e. 0.1 mm thicker in printed sample using second orientation than as required by the standard. The smallest thickness deviation from the standard was measured in width dimension of a sample printed using first orientation (0.13 mm). As with the length dimension, the closest dimension to the standard was resulted from the third orientation product, i.e 0.2 mm. Tensile test done on all the specimens produced with those three orientations shows that the highest tensile strength was obtained in sample from second orientation deposition, i.e. 7.66 MPa followed by the first and third orientations products, i.e. 6.8 MPa and 3.31 MPa, respectively.

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Rapid prototyping is a group of techniques used to quickly scale physical parts or assemblies using three-dimensional computeraided design (CAD) data. The process of 3D printing constructs three-dimensional objects from CAD models, usually by adding layers by a layer of material in a row. Therefore it is also called making addictive manufacturing. Along with the development of rapid prototyping, there are many choices of materials on the market to make parts of 3D printing. The material can be in the solid filament, liquid resin, or powder. Solid filament FDM technology material is the most commonly used by industrythese materials such as ABS, PLA, PETG, HIPS, and others. In 3D printing products, several variables can be observed to produces specific responses desirable. Some of the responses are the efficiency of materials, dimensional accuracy of mechanical, and others. This research was conducted to compare ABS and PLA materials in the fused deposition modeling process. The strength and dimensional accuracy are the response that used in this study. The study reports that ABS has more significant tensile strength than PLA. The tensile strength of ABS is 7.66 MPa and 1.79 for PLA. PLA found has a more accurate dimension compare to ABS. Both on length and thickness, deviation of PLA lower than ABS. On a length, deviation of PLA was 0.06 mm and 0.86 for ABS. On thickness, deviation of PLA was 0.04 and 0.05 for ABS.