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This paper aims to perform thermal and mechanical characterization for silver-based sintered thermal joints. Layer quality affects thermal and mechanical performance, and it is important to achieve information about how materials and process parameters influence them.

Thermal investigation of the thermal joints analysis method was focused on determination of thermal resistance, where temperature measurements were performed using infrared camera. They were performed in two modes: steady-state analysis and dynamic analysis. Mechanical analysis based on measurements of mechanical shear force. Additional characterizations based on X-ray image analysis (image thresholding), optical microscope of polished cross-section and scanning electron microscope image analysis were proposed.

Sample surface modification affects thermal resistance. Silver metallization exhibits the lowest thermal resistance and the highest mechanical strength compared to the pure Si surface. The type of dynamic analysis affects the results of the thermal resistance.

Investigation of the layer quality influence on mechanical and thermal performance provided information about different joint types.

The purpose of this paper is to study the effect of nano hydroxyapatite (HA) and graphene oxide (GO) particles on thermal and mechanical performances of 3D printed poly(ε-caprolactone) (PCL) filaments used in bone tissue engineering (BTE).

Raw materials were prepared by melt blending, followed by 3D printing via 3D Discovery (regenHU Ltd., CH) with all fabricating parameters kept constant. Filaments, including pure PCL, PCL/HA and PCL/GO, were tested under the same conditions. Several techniques were used to mechanically, thermally and microstructurally evaluate properties of these filaments, including differential scanning calorimetry, tensile test, nano indentation and scanning electron microscope.

Results show that both HA and GO nano particles are capable of improving mechanical performance of PCL. Enhanced mechanical properties of PCL/HA result from reinforcing effect of HA, while a different mechanism is observed in PCL/GO, where degree of crystallinity plays an important role. In addition, GO is more efficient at enhancing mechanical performance of PCL compared with HA.

For the first time, a systematic study about effects of nano HA and GO particles on bioactive scaffolds produced by additive manufacturing for BTE applications is conducted in this work. Mechanical and thermal behaviors of each sample, pure PCL, PCL/HA and PCL/GO, are reported, correlated and compared with literature.

The purpose of this paper is to describe the fabrication and characterization of poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyexanoate] (PHBHHx) tissue engineering scaffolds with anatomical shape and customized porous structure.

Scaffolds with external shape and size modeled on a critical size segment of a rabbit’s radius model and an internal macrochanneled porous structure were designed and fabricated by means of a computer-aided wet-spinning (CAWS) technique. Morphological, thermal and mechanical characterization were carried out to assess the effect of the fabrication process on material properties and the potential of the PHBHHx scaffolds in comparison with anatomical star poly(e-caprolactone) (*PCL) scaffolds previously validated in vivo.

The CAWS technique is well suited for the layered manufacturing of anatomical PHBHHx scaffolds with a tailored porous architecture characterized by a longitudinal macrochannel. Morphological analysis showed that the scaffolds were composed by overlapping layers of microfibers with a spongy morphology, forming a 3D interconnected network of pores. Physical-chemical characterization indicated that the used technique did not affect the molecular structure of the processed polymer. Analysis of the compressive and tensile mechanical properties of the scaffolds highlighted the anisotropic behavior of the porous structure and the effect of the macrochannel in enhancing scaffold compressive stiffness. In comparison to the *PCL scaffolds, PHBHHx scaffolds showed higher compressive stiffness and tensile deformability.

This study shows the possibility of using renewable microbial polyester for the fabrication of scaffolds with anatomical shape and internal architecture tailored for in vivo bone regeneration studies.

The purpose of this study is to highlight the direct fabrication of rapid tooling (RT) with desired mechanical, tribological and thermal properties using fused deposition modelling (FDM) process. Further, the review paper demonstrated development procedure of alternative feedstock filament of low-cost composite material for FDM to extend the range of RT applications.

The alternative materials for FDM and their processing requirements for fabrication in filament form as reported by various researchers have been summarized. The literature demonstrates the role of various post-processing techniques on surface finish of FDM prints. Further, low-cost materials for feedstock filament have been investigated experimentally to check their adaptability/suitability for commercial FDM setup. The approach was to realize the requirements of FDM (melt flow rate, flexibility, stiffness, glass transition temperature and mechanical strength), necessary for the successful run of an alternative filament. The effect of constituents (additives, plasticizers, surfactants and fillers) in polymeric matrix on mechanical, tribological and thermal properties has been investigated.

It is possible to develop composite material feedstock as filament for commercial FDM setup without changing its hardware and software. Surface finish of the parts can further be improved by applying various post-processing techniques. Most of the composite parts have high mechanical strength, hardness, thermal stability, wear resistant and better bond formation than standard material parts.

Future research may be focused on improving the surface quality of parts fabricated with composite feedstock, solving issues related to the uniform distribution of filled materials during the fabrication of feedstock filament which in turns further increases mechanical strength, high dimensional stability of composite filament and transferring the technology from laboratory scale to various industrial applications.

Potential applications of direct fabrication with RT includes rapid manufacturing (RM) of metal-filled parts and ceramic-filled parts (which have complex shape and cannot be rapidly made by any other manufacturing techniques) in the field of biomedical and dentistry.

This new manufacturing methodology is based on the proper selection and processing of various materials and additives to form high-performance, low-cost composite material feedstock filament (which fulfil the necessary requirements of FDM process). Finally, newly developed feedstock filament material has both quantitative and qualitative advantage in RT and RM applications as compared to standard material filament.

This paper aims to develop thermal analysis method of thermal joints characterization. The impact on convection on thermal resistance analysis with use thermography for silver-based thermal joints were investigated for non-metallized and metalized semiconductor surfaces. Heat transfer efficiency depends on thermal conductivity; radiation was used to perform thermographic analysis; the convection is energy loss, so its removing might improve measurements accuracy.

Investigation of thermal joints analysis method was focused on determination of convection impact on thermal resistance thermographic analysis method. Measuring samples placed in vacuum chamber with lowered pressure requires transparent window for infrared radiation that is used for thermographic analysis. Impact of infrared window and convection on temperature measurements and thermal resistance were referred.

The results showed that the silicon window allowed to perform thermal analysis through, and the convection was heat transfer mode which create 15% energy loss.

It is possible to measure thermal resistance for silver-based thermal joints with convection eliminated to improve measurements accuracy.

The purpose of this paper is to present the review of natural fibre composites as well as a specific type of fibre, i.e., sugar palm fibre and its composites.

The approach of this review paper is to present previous work on natural fibres and their composites. Then a review of several important aspects such as history, origin, botanic description, distribution, application and characterisation of sugar palm tree, and its fibre is presented. Finally a review of properties and characterisation of sugar palm composites is presented.

Findings of this review include the potential application of natural fibres and their composites for engineering application, the use of sugar palm and its fibres, as well as the suitability of sugar palm composites in engineering application after conducting review of their performance and characterisation.

The value of this review is to highlight the potential of natural fibres, natural fibre composites, sugar palm, sugar palm fibres and sugar palm composites as materials for engineering applications.

This paper aims to feature preparation and characterization of thiokol oligomer functionalized MWCNTs/epoxy nanocomposites using low molecular weight polyamide as curing agent.

First, thiokol oligomer functionalized MWCNTs (MWCNTs-TO) were prepared through hydroxylation, silanization and graft modification of MWCNTs. The nanocomposite specimens were fabricated through sonication and cast moulding process. The authors then investigated the impact of MWCNTs-TO content on mechanical and thermal properties of the nanocomposites.

MWCNTs-TO with grafting ratio of 17.5 Wt.% was synthesized and characterized with X-ray photoelectron spectroscopy, thermal gravimetric analysis, Fourier transform infrared and scanning electron microscopy. The obtained epoxy nanocomposites exhibit improved mechanical properties and thermal stability with MWCNTs-TO added. Moreover, desirable results were obtained at 0.75 Wt.% of MWCNTs-TO loading: the young’s modulus, tensile, flexural and impact strength increased by 24.6,72.8,34.8 and 82.7%, respectively, compared to the neat epoxy. The improvement of mechanical properties is mainly attributed to enhanced interfacial interaction and dispersion between the covalent functionalized MWCNTs and epoxy matrix.

A flexible thiokol oligomer was successfully grafted onto MWCNTs via a mild route. Nanocomposites with excellent interfacial interaction and dispersion between MWCNTs-TO and the epoxy matrix have been successfully fabricated and investigated.

This method provided a mild and practical approach to improve the performance of MWCNTs epoxy nanocomposites.

A flexible thiokol oligomer was successfully covalent grafted onto MWCNTs via a mild route. Nanocomposites with excellent interfacial interaction and dispersion between MWCNTs-TO and the epoxy matrix have been successfully fabricated and investigated.

The paper's aim is to investigate improvement of strength and adhesion of silicone‐acrylic hybrid systems.

The presence of Si‐C bonds in phenyl silicone should be able to improve strength, adhesion and thermal properties of phenyl silicone‐acrylic polyol coating. Different weight ratios of phenyl silicone and acrylic polyol resins were blended in order to obtain the composition for optimum strength, adhesion and thermal properties. Strength was evaluated using an impact resistance tester. Coating adhesion was studied by measuring the contact angle and performing cross hatch cutting. The thermal properties were studied using differential scanning calorimetry.

Blending phenyl silicone intermediate resin with acrylic polyol resin showed significant improvement in strength and adhesion properties compared to pure acrylic polyol resin. This paper shows that the composition of such coatings influences the glass transition temperature (T_g), which in turn affects the strength and adhesion properties of the coatings. The coating consisting of 30 per cent silicone resin and 70 per cent acrylic resin showed good adhesion and impact resistance properties on cold roll mild steel panels.

Findings may be useful in the development of heat resistant and anti‐corrosion paints.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resins.

Durability and functionality of the coating critically depend on the strength and adhesion properties of the materials. This may be a useful source of information for the development of organic‐inorganic coatings.

To meet the state‐of‐the‐art requirements of BGA assemblies necessitates direct coupling of field conditions, simulation tools for life‐time study and advanced experiments for the assessment of physical degradation. For conventionally soldered SMD components, transformations between test and field conditions are still not completely known. For new types of array components, the answers critically depend upon ‘Component age’ and change in fatigue mechanisms. The increasing complexity of microelectronic assemblies and the hidden joints of BGAs lead to an increase in reliability problems in this field. Therefore, to describe failure‐free times for different applications, fatigue relevant parameters of the ball solder joints need to be studied. With regard to the thermal coefficient of expansion, BGAs are mainly asymmetrical, consequently residual strains and stresses are generated in the solder joint array. The level of strains and stresses depends upon the global and local mismatch, the applied operating conditions and the temperature distribution in the ball solder joint array (chip location, ambient and operating temperature). For thermo‐mechanical cycling procedures, hold and ramp times at upper and lower temperatures (e.g., −20°C/+100°C) are used to initiate strains in materials and interfaces. BGAs and PCBs show comparable thermal levels with regards to the test procedures mentioned before, and the resulting stress conditions in the ball solder joints are a function of package size, DNP, etc. The test results with regard to the generation of cracks are not directly comparable to the fatigue behaviour under operating conditions. Therefore, different types of degradation tests were developed: thermo‐mechanical, mechanical, electrical and/or corrosive procedures. Depending upon the chip location in the BGA package (symmetrically: PBGA, TBGA, CBGA; asymmetrically :MCM‐BGA) frequencies, lateral and vertical temperature distribution under simulated power dissipations, and the internally generated heat will be used to induce stresses in the ball solder joints. For different values of power dissipation and ambient conditions, thermal measurements were performed, screening the top to the bottom side of the BGA and the array field. The resulting information is a precondition in order to define power cycle parameters. For different test procedures, locations of defects, crack initiation and growth in ball solder joints were studied by metallographic analysis. The practical measurements serve as analytical input to compare thermal and power cycle tests and they are a necessary step to perform a lifetime prediction.

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.