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This study aims to characterize the properties of natural cellulose fiber from the pseudo-stems of the curcuma zedoaria plant.

The fiber was extracted using the biological retting process (cold-water retting). The intrinsic fiber properties obtained were used to evaluate the possibility of using fiber for textile applications.

The average length of a curcuma zedoaria fiber was 34.77 cm with a fineness value of 6.72 Tex. A bundle of curcuma zedoaria fibers was comprised of many elementary fibers. Curcuma zedoaria had an irregular cross-section, with the lumen having a varied oval shape. Curcuma zedoaria fibers had tenacity and elongation value of 3.32 gf/denier and 6.95%, respectively. Curcuma zedoaria fibers had a coefficient of friction value of 0.46. Curcuma zedoaria fibers belong to a hygroscopic fiber type with a moisture regain value of 10.29%.

Extraction and Characterization of Curcuma zedoaria Pseudo-stems Fibers for Textile Application.

The purpose of this study was to characterize the fiber from Curcuma longa (turmeric) stems. The fiber’s properties were used to assess its potential for textile yarn production.

The natural fiber used in this investigation was extracted from agricultural waste through a cold water-retting process.

The Curcuma longa fiber had a crystallinity of 50%. Cellulose, hemicellulose and lignin were detected in the fibers’ Fourier transform infrared spectra. A Curcuma longa fiber bundle contains several constituent fibers. The fibers exhibited an irregular cross-section, with a variable oval shape for the lumen. The fibers of Curcuma longa averaged 30.22 cm in length. The fineness of the fibers was 6.58 Tex. In this study, Curcuma longa fibers had an 11.30% moisture regain. The tensile strength of the fibers was 19.18 g/Tex. Curcuma longa fibers showed a break elongation of 9.79%. The fiber coefficient of friction was 0.3.

Curcuma longa has characteristics that make it appropriate for industrial uses like spinning. Thus, it is possible to use Curcuma longa fiber as a raw material for textiles.

This study aims to analyse cellulose fibres extracted from the pseudo-stems of Cymbopogon citratus and evaluate their properties in non-woven fabric production.

The water retting method was used for fibre extraction, and intrinsic fibre qualities were examined to assess their suitability for textile applications. A thermal bonding technique, using a hot press machine and polylactic acid powder as a binder, was applied for non-woven fabric development.

The retted fibres had an average length of 156 mm and a fineness value of 5.73 tex. The fibre’s tenacity and elongation values were 1.33 gf/denier and 12.78%, respectively. Fourier transform infrared analysis confirmed the presence of major cellulose components. The fibre’s crystallinity and friction coefficient were 50% and 0.3, respectively. C. citratus fibre exhibited hygroscopic characteristics with a moisture regain of 10.65%. Experimental non-woven fabrics (70% C. citratus fibre, 30% polylactic acid powder) demonstrated consistent weight and thickness, with variations in tensile strength. Moisture regain values for non-woven fabrics were approximately 7.6%.

The features of C. citratus fibre, obtained with the water retting process, exhibited suitability for textile applications. Three experimental non-woven fabrics comprising of C. citratus fibre and polylactic acid powder were produced with three different pressing temperatures. The tensile strength properties of these fabrics were influenced by pressing temperature.

The purpose of this study is to analyse the characteristics of cellulose fibres derived from the pseudo-stems of Curcuma longa and to evaluate the properties of non-woven fabric produced using these fibres.

The fibres were extracted via a decortication method. The acquired intrinsic qualities of the fibres were used to assess the feasibility of using them in textile applications. The thermal bonding approach was used for the development of the non-woven fabric, using a hot press machine with low-melt polyester fibre as a binder.

The mean length of Curcuma longa fibres was determined to be 52.73 cm, with a fineness value of 4.00 tex. The fibres exhibited an uneven cross-sectional morphology, characterized by a diverse range of oval-shaped lumens. The fibre exhibited a tenacity of 1.45 g/denier and an elongation value of 4.30%. The fibres possessed a moisture regain value of 11.30%. The experimental non-woven fabrics had consistent weight and thickness, while exhibiting different properties in terms of tensile strength and air permeability, with Fabric C having the highest tensile strength and the lowest air permeability value.

The features of Curcuma longa fibre, obtained with the decortication process, exhibited suitability for textile applications. Three experimental non-woven fabrics comprising different compositions of Curcuma longa fibre and low-melt polyester fibre were produced. The tensile strength and air permeability properties of these fabrics were influenced by the composition of the fibres.

The purpose of this study is to increase the thermal and mechanical properties of the photopolymer by filling with the copper powder for the application of rapid tooling.

In this study, the photopolymer is filled with the different loading of copper powder for investigating the thermal and mechanical properties of the copper/photopolymer composite. The thermal properties of the copper/photopolymer composite are characterized with the degradation temperature and with the thermal conductivity. The mechanical properties of copper/photopolymer composite are performed with the tensile strength and hardness testing. Moreover, the copper/photopolymer composite is imaged by using a scanning electron microscopic with energy dispersive spectroscopy.

The tensile strength of the copper/photopolymer composite is increased over 45 per cent at 20 phr copper loading. The hardness of the photopolymer has a negative correlation with the increasing copper loading and is decreased about 28.5 per cent at 100 phr copper loading. The degradation temperature of the copper/photopolymer composite is increased about 7.2 per cent at 70 phr copper loading. The thermal conductivity of the copper/photopolymer composite is increased over 65 per cent at 100 phr copper loading.

The photopolymer used in rapid prototyping system is generally fragile and has poor thermal properties. This study improves the thermal and mechanical properties of the photopolymer with the copper filling which has been never investigated in the field of rapid prototyping applications.

The purpose of this paper is to develop a novel process of integral ceramic molds for investment casting of hollow turbine blades.

At first, a resin pattern of a hollow turbine blade prototype is fabricated by stereolithography (SL). And then aqueous gelcasting process is utilized to fill the resin pattern with ceramic slurry of low viscosity and low shrinkage, through in situ polymerization of the slurry a ceramic mold is formed. At last, the ceramic mold for investment casting of hollow turbine blade is obtained by vacuum drying, pyrolyzing and sintering.

An integral ceramic mold is successfully fabricated by combining SL and gelcasting process, cores and shell are connected with each other and thus high relative position accuracy is guaranteed. Properties of integral ceramic mold at room temperature and high temperature satisfy the requirements of directional casting for complex‐shaped thin‐walled blades.

Because the integral ceramic mold is a close body, it is very difficult to directly measure its inner dimensions and the relative position accuracy of cores and shell, and the further research is needed.

This method enhanced the versatility of using SL prototype in the fabrication of integral ceramic mold for investment castings. Although this paper took a hollow turbine blade as an example, this method is also capable of fabricating integral ceramic molds for other complex investment castings.

The purpose of the present study is process capability analysis of fused deposition modelling (FDM) process as rapid pattern making (RDPM) solutions for plastic components.

Starting from the identification of component, prototypes with ABS plastic material were produced and dimensional measurements were made with coordinate measuring machine (CMM). Some important mechanical properties were also compared to verify the suitability of the components.

The study highlighted the best settings of orientation, support material quantity for the selected component as a case study on FDM machine from dimensional accuracy and economic point of view as RDPM solution for plastic components.

This process ensures rapid production of statistically controlled pre-series technological prototypes and proof of concept at less production cost and time. Final components produced are acceptable as per ISO standard UNI EN 20286-I and DIN16901.

The results of the study suggest that FDM process lies in ±4.5 sigma (σ) limit in regard to dimensional accuracy of plastic component is concerned and may be gainfully employed as RDPM solution for bio-medical applications.

The purpose of this paper is to propose an imperfect symmetry transform framework for orbital prosthesis modelling.

Current models of patients with orbital defects have imperfect symmetries. Commonly used methods, such as principal component analysis (PCA) or iterative closest points algorithm (ICP), do not detect perfect symmetries and therefore produce poor results. The authors propose an improved ICP algorithm based on the M‐estimator, which can remove outliers from the optimization and detect incorrect symmetry. Using this algorithm, the mid‐facial plane of a patient's facial model can be precisely obtained despite perturbation of the facial shape due to the defect.

The results showed that the orbital prosthesis fitted well to the patient's appearance. Clinical applications confirmed that this framework is attractive and has the potential for use in creating desired orbital prostheses or other bilateral maxillofacial prostheses in daily clinical practice.

The method described in this report will improve the fabrication accuracy of orbital prostheses or other bilateral maxillofacial prostheses.

This imperfect symmetry transform framework has great potential for use in clinical applications because of its advantages over other existing methods in terms of accuracy.

High-performance wrought aluminum alloys, particularly AA6061, are pivotal in industries like automotive and aerospace due to their exceptional strength and good response to heat treatments. Investment casting offers precision manufacturing for these alloys, because casting AA6061 poses challenges like hot cracking and severe shrinkage during solidification. This study aims to address these issues, enabling crack-free investment casting of AA6061, thereby unlocking the full potential of investment casting for high-performance aluminum alloy components.

Nanotechnology is used to enhance the investment casting process, incorporating a small volume fraction of nanoparticles into the alloy melt. The focus is on widely used aluminum alloy 6061, utilizing rapid investment casting (RIC) for both pure AA6061 and nanotechnology-enhanced AA6061. Microstructural characterization involved X-ray diffraction, optical microscopy, scanning electron microscopy, differential scanning calorimetry and energy dispersive X-ray spectroscopy. Mechanical properties were evaluated through microhardness and tensile testing.

The study reveals the success of nanotechnology-enabled investment casting in traditionally challenging wrought aluminum alloys like AA6061. Achieving crack-free casting, enhanced grain morphology and superior mechanical properties, because the nanoparticles control grain sizes and phase growth, overcoming traditional challenges associated with low cooling rates. This breakthrough underscores nanotechnology's transformative impact on the mechanical integrity and casting quality of high-performance aluminum alloys.

This research contributes originality and value by successfully addressing the struggles in investment casting AA6061. The novel nano-treating approach overcomes solidification defects, showcasing the potential of integrating nanotechnology into rapid investment casting. By mitigating challenges in casting high-performance aluminum alloys, this study paves the way for advancements in manufacturing crack-free, high-quality aluminum alloy components, emphasizing nanotechnology's transformative role in precision casting.

The purpose of this paper is to optimize the process parameters to obtain the best dimensional accuracy, surface finish and hardness of the castings produced by using fused deposition modeling (FDM)-based patterns in investment casting (IC).

In this paper, hip implants have been prepared by using plastic patterns in IC process. Taguchi design of experiments has been used to study the effect of six different input process parameters on the dimensional deviation, surface roughness and hardness of the implants. Analysis of variance has been used to find the effect of each input factor on the output. Multi-objective optimization has been done to find the combined best values of output.

The results proved that the FDM patterns can be used successfully in IC. A wax coating on the FDM patterns improves the surface finish and dimensional accuracy. The improved dimensional accuracy, surface finish and hardness have been achieved simultaneously through multi-objective optimization.

A thin layer of wax is used on the plastic patterns. The effect of thickness of the layer has not been considered. Further research is needed to study the effect of the thickness of the wax layer.

The results obtained by the study would be helpful in making decisions regarding machining and/or coating on the parts produced by this process.

In this paper, multi-objective optimization of dimensional accuracy, surface roughness and hardness of hybrid investment cast components has been performed.