Effect Of Manufacturing Parameters Research Articles

Evaluating deformation in FRP boat: Effects of manufacturing parameters and working conditions

Abstract Fiber-reinforced plastic (FRP) is utilized in the fabrication of the primary structures of FRP boats. A majority of these structures are produced using molds. Subsequently, these products often experience deformation upon being released from the mold, as well as when they are exposed to high temperatures. Hence, it is crucial to carry out experimental investigations and evaluations related to the deformation of laminated composite structures. The specimens, which are in the form of L-shapes and curve-shapes, are constructed using unsaturated polyester resin and fiberglass material. The study focuses on two independent variables, namely the percentage of hardeners and the temperature during the manufacturing process. The output factor under examination is deformation, which is measured on these specimens. Subsequently, all of the specimens are subjected to varying levels of temperature using an oven as the working condition. The deformation is further assessed based on the experimental findings and regression equation. The results indicate that as the rate of hardener and temperature increase, the level of deformation decreases. Additionally, it was observed that when the temperature rises from 500 to 800°C, the specimens with initial deformation values that are either too high or too low undergo rapid changes. Moreover, the experimental equations can be utilized to predict the values of deformation or input factors.

Evaluations of microstructure and electrochemical characteristics of Al-Si-Cu/clay nanocomposites in two corrosive solutions

Effects of manufacturing parameters on the electrochemical properties of aluminum-based nanocomposite with clay reinforcement have been investigated as a new study. Tafel polarization and electrochemical impedance spectroscopy tests at ambient temperature and in two corrosive environments were used to investigate the characteristics of the fabricated nanocomposites. Examination of different specimen microstructures was performed by optical and scanning electron microscopy before and after electrochemical tests. Electrochemical measurements indicated that nanocomposites had a higher corrosion rate in 0.6 M NaCl solution compared to the Al-Si-Cu matrix. The lower content of the Si and AlCu4 precipitates was a major parameter in reducing corrosion attacks. However, nanocomposites exhibited a higher corrosion resistance in comparison with the aluminum matrix in 0.02 M H3BO3 solution. Such an increase range was about 25.3–70.3 % concerning nanocomposites. The highest resistance was attributed to the nanocomposite stirred for 2 mins at 800 °C. In this situation, a higher content of Si precipitates (up to 30 %) with a small size was an effective factor in forming a passive layer at the matrix surface and acting as an obstacle for further corrosive ions diffusion toward the inner layer of the material.

Effects of manufacturing parameters on mechanical interface properties of thin wood veneer laminates

This study explores fast manufacturing techniques for thin wood laminates made from European beech veneers and 1-component polyurethane adhesive. Manufacturing factors such as pressure and pressing time are investigated following well-established standards developed for fibre-reinforced materials (ASTM D5528 and ASTM D7905). Mode I and Mode II interlaminar fracture properties are calculated to quantify the effects of the different manufacturing techniques on the bond quality. It is found that pressing time and pressure can be minimised to 10 minutes and 0.1 MPa from 75 min and 1.0 MPa as suggested by the adhesive manufacturer, without reducing critical Mode I strain energy release rates of around 500 to 600 J/m2. However, the standard deviation of these properties increases with decreasing pressure and pressing time. Furthermore, the results show that while ASTM D5528 for Mode I testing can be used with thin wood veneer laminates, the ASTM D7905 for Mode II fracture testing is not directly applicable to these materials.

Manufacturing and static performance of porous aerostatic bearings

According to the common body of knowledge, aerostatic bearings invariably need narrow manufacturing tolerances to ensure maximal load capacity and high stiffness. This study experimentally investigates the manufacturing of porous material aerostatic bearings and the effect of manufacturing parameters on the performance properties of the bearings. During the study, samples were manufactured using different methods, and the geometrical and performance properties of each sample were inspected. The bearing performance measurement device developed during the study is introduced. The results present the dependence between manufacturing parameters and bearing properties under varying load and operating pressure conditions. The results clearly suggest that effect of bearing surface roughness on load capacity is small; meanwhile, surface planarity has a major impact on load capacity.

Modified Method for Surface Probabilistic Risk Assessment of Aero Engine Compressor Disks Considering Shot Peening

Aero engine compressor disks are typically life-limited parts and it is necessary to secure them through the implementation of an engineering plan and a manufacturing plan. Specifically, the engineering plan recommends the quantification of the safety of life-limited parts on the basis of probabilistic risk assessment (PRA). However, the direct correlation between plans is limited, and the effect of manufacturing parameters on the safety of life-limited parts remains to be investigated. Shot peening, as a typical method of surface manufacturing, can significantly improve the safety of life-limited parts. Therefore, a modified mathematical surface PRA method considering shot peening parameters is developed in this paper to further bridge the design and manufacturing processes. Additionally, a general database is established using the response surface method to overcome the simulation complexity. On the basis of this method and the general database, an innovative direct and efficient determination of key shot peening parameters through failure risk in the design stage is proposed. The results indicate that failure risk decreased by 3.26%, 11.31%, and 9.71%, respectively, with increasing number, diameter, and velocity of shots, with the effect of diameter being the greatest. In addition, the method improves the efficiency of determining the key parameters by 75.80%, thus satisfying the requirements of abundant and efficient iterations during the design stage.

Thermal analysis for in-situ consolidation in the AFP process

An analytical approach was developed for assessing the thermal history of thermoplastic composites during tape placement for in-situ consolidation of the automated fiber placement (AFP) technique. In this study, the heat-conduction equation is developed and solved for internal energy instead of temperature because the diffusivity does not significantly change over a wide range of temperatures in the AFP process, despite the significant change in the specific heat and conductivity. The three-dimensional internal energy history is derived in an integrated form using the Green function technique. The temperature field obtained from the internal energy field agreed with the finite element solution, where the temperature-dependent thermal properties were considered. The effects of manufacturing parameters, such as the placement speed and thickness of the placed laminates, on the thermal history of laminated composites during AFP are discussed using the present approach and finite element analysiss.

A review of the different fabrication techniques of porous Mg structures considering the effect of manufacturing parameters on corrosion rate and mechanical properties in the bio application

A review of the different fabrication techniques of porous Mg structures considering the effect of manufacturing parameters on corrosion rate and mechanical properties in the bio application

The development and characterization of carbon nanofiber/polylactic acid filament for additively manufactured piezoresistive sensors

In this work, an investigation into the effects of manufacturing parameters on carbon nanofiber (CNF)/polylactic acid (PLA) filament for fused filament fabrication (FFF) additive manufacturing (AM)-produced strain sensors was conducted. A design of experiments (DOE) approach was undertaken to explore the impact of CNF weight fraction, extrusion temperature, and number of extrusions on sensor performance. The initial extrusion combined pulverized PLA material and CNFs via a dry melt-mixing process. Through the DOE process, it was found that extruding CNF/PLA material at 185 °C for two total extrusions yielded material with dramatic improvements in electrical properties compared to unmodified material. Using the optimal manufacturing procedure, piezoresistive dog-bone shaped sensors were manufactured via FFF with 5.0, 7.5, and 10.0 wt % CNF/PLA filament and three different sizes. Piezoresistive testing under monotonic and cyclic loading conditions revealed strong and repeatable behavior from the piezoresistive AM sensors produced with 7.5 and 10.0 wt % CNFs. In general, 7.5 wt % CNF/PLA sensors showed greater strain sensitivity than 10.0 wt % CNF/PLA sensors for monotonic loading. Additionally, sensor size appeared to contribute significantly to the performance of 7.5 wt % CNF/PLA sensors. However, the 10.0 wt % CNF/PLA sensors exhibited greater repeatability in their piezoresistive response, and sensor size had much less impact on strain sensing performance. The printed sensors also exhibited a strong response under cyclic loading, however, variability in their piezoresistive response was significantly higher than under monotonic loading conditions. The results of this study are an important step towards the realization of low-cost, easily produced, and highly customizable strain sensors produced via FFF technology.

The effect of manufacturing parameters on various composite plates under ballistic impact

In this study, the usability of several composite plates in level III and level IV body armors were examined, along with the ballistic resistance, protection level, and production parameters of each plate. For level III protection, composite panels are made using the heat pressing method under various pressures, and for level IV composites, ceramic plates of various thicknesses are reinforced on the back with various composite materials. Ballistic tests using the NIJ standards were performed on the created composite panels. There were delaminations between the layers as a result of the ballistic test in the level III protective panels produced at 140 bar pressure, but there was no puncture in the panels produced at 250 bar pressure, and the depth of trauma was reduced to a minimum. These observations were made using samples produced at 90 bar pressure under controlled conditions. Level IV panels were subjected to dry and wet ballistic tests, and the results of these tests showed that K-flex reinforced ceramics were impervious to punctures. It has been found that aramid-reinforced epoxy ceramic panels and UD H62 reinforced ceramics have superior ballistic qualities and are 6% lighter.

Effects of manufacturing parameters, heat treatment, and machining on the physical and mechanical properties of 13Cr10Ni1·7Mo2Al0·4Mn0·4Si steel processed by laser powder bed fusion

This study investigates the effects of build orientations, heat treatment, and mechanical machining (as processing and post-processing factors) on the microstructure, quasi-static mechanical properties, strain hardening, notch toughness, and residual stress of additive manufactured 13Cr10Ni1·7Mo2Al0·4Mn0·4Si maraging stainless steel, known commercially as CX. The material investigated in this research was processed using the laser powder bed fusion (L-PBF) method as the additive manufacturing process. The results show that stainless steel CX had an anisotropic behavior under quasi-static tensile loads in its as-built condition. However, heat treatment significantly increased the strength of the material and eliminated the anisotropy in the strength levels. In addition, building orientation did not significantly affect the microstructure, hardness, and notch toughness. Further, retained austenite proved to have a role in determining the ductility and strain hardening of CX. Finally, the heat treatment utilized in this study proved to be effective in improving the mechanical properties employing shorter times and lower temperatures compared to the treatments used in other studies from the literature.

Thermomechanical characterization of metal-polyurethane bonded joints: effect of manufacturing parameters and working temperature

ABSTRACT Metal-elastomer bonded joints are typical of different industrial applications, specifically pallet truck wheels, where the solid elastomeric layer is bonded to the metal body. This paper focuses on the effect of manufacturing parameters and working temperature, on the shear strength of a metal-elastomer bonded joint. Through a comprehensive experimental test plan, the paper investigates the effect of thermal conditioning of the adhesive, shot peening of the metal adherend, type of solvent-based adhesive, and working temperature of the joint. The test plan uses a TAST-like specimen with a sandwich configuration (metal-elastomer-metal), loaded in order to originate a nearly pure-shear stress state. The results show which parameters influence most the shear strength of the joint helping the designer in maximizing the load-carrying capacity of the joint.

Effects of manufacturing parameters on properties of rubberwood-cross laminated timber manufactured via hot pressing

In this study, cross-laminated timber (CLT) was manufactured from rubberwood via hot pressing. The effects of manufacturing parameters, such as resin content and clamping pressure, on the following properties of CLT panels were investigated: density (ρ), water absorption (WA), thickness swelling (TS), bonding strength (BS), compressive strength in the major strength direction of CLT (σmajor), compressive strength in the direction perpendicular to the flat plane of CLT (σFlat)), and rolling shear strength (RS). The relationships among the properties of the CLT panel, those the original rubberwood material, and the manufacturing parameters was also explored. The results showed that the resin content and clamping pressure did not significantly affect most of the examined properties of the CLT panels. The ρ, WA, σmajor, σFlat, and RS of the panels could be estimated directly from the properties of the original rubberwood, while the TS could be estimated directly from the clamping pressure applied on the panel. However, no such relationship was found for the BS value. Compared with typical softwood-CLT, the rubberwood-CLT exhibited superior mechanical properties. This implies that CLT made of rubberwood can achieve better structural performance than standard CLT can.

Effects of manufacturing parameters and mechanical post-processing on stainless steel 316L processed by laser powder bed fusion

Abstract Stainless steel 316L is a frequently used metal in additive manufacturing owing to its favorable strength-ductility synergy and corrosion resistance, and laser powder bed fusion (L-PBF) is the most commonly applied additive manufacturing method for processing 316L. Manufacturing components from stainless steel 316L via L-PBF benefits the geometrical accuracy of the process and properties of the material simultaneously. Although alloy 316L has been used in additive manufacturing for a long time, its strengthening mechanisms and microstructure have yet to be fully understood. Thus, this study aimed to perform a comprehensive investigation of the microstructural features and mechanical properties of this alloy. A thorough review of other studies on stainless steel 316L processed via L-PBF is provided, along with experimental results, to elucidate the mechanisms controlling and influencing the properties of this material. Microstructural analysis, hardness measurements, and tensile, fatigue, and Charpy tests were performed. The results showed that stainless steel 316L processed by L-PBF could satisfactorily replace its conventionally manufactured counterparts for service under static, cyclic, and impact loads. However, under cyclic loading, the fatigue performance of the additively manufactured material may require enhancement by machining or mechanical post-processing.

High-quality cutting polarizing film (POL) by 355 nm nanosecond laser ablation

With the development of ultra-high screen-to-body ratio liquid crystal display (LCD) screen, extremely high requirements have placed on the cutting quality of LCD screen polarized film (POL). In this study, high-quality cut obtained using a 355 nm (ultraviolet light) nanosecond laser, and the cutting quality was analyzed with laser ablation process as the core. Firstly, by comprehensive experiments, narrowest heat-affected zone (HAZ) width of 12.07 ± 0.4 μm obtained when pulse repetition rate was 190 kHz, cutting speed was 40 mm/s and repeat times of laser cutting was 4, and the cross-section was smooth without obvious taper. Secondly, POL cutting mechanism with laser ablation as the core was summarized by analyzing the thermal decomposition process of POL. Finally, based on experimental results and laser ablation mechanism, effects of manufacturing parameters on cutting quality obtained. This work provides manufacturing technology reference and mechanism support for high-quality POL laser cutting.

Effect of Manufacturing Parameters on the Mechanical and Corrosion Behavior of Selective Laser‐Melted 15‐5PH Stainless Steel

The effect of manufacturing parameters on mechanical and corrosion resistance is investigated using tensile tests and electrochemical experiments for selective laser‐melted 15‐5PH stainless steel. The results demonstrate that when laser power is decreased to 150 W and scanning speed increased to 1400 mm s−1, manufacturing defects increase. Plasticity and corrosion resistance reduce significantly. Cracks mainly originate from manufacturing defects and extend along the interface between molten pools. Corrosion occurs near manufacturing defects. Finally, the most suitable laser energy density is 130 J mm−3 for 15‐5PH stainless steel.

Effects of manufacturing parameters on performance of fluidic oscillators for aerodynamic flow control

An investigation is conducted into the effects of dimensional variation, material selection, and manufacturing process on the performance characteristics of a self-oscillating fluidic oscillator. Measurements of oscillation frequency, inlet pressure, and jet profile are performed for actuators having varying nozzle and cavity dimensions. Actuators made of aluminum and carbon fiber reinforced polyetherketoneketone are tested, and the effects of varying manufacturing processes between machining, selective laser sintering, stereolithography, and injection molding are assessed. Models based on dimensionless variables are used to characterize the variation in frequency and inlet pressure for a given mass flow rate. Variation of the nozzle geometry and cavity shoulder width influence the oscillation frequency, and variation of nozzle geometry affects the required driving pressure. Dimensional variations due to manufacturing process tolerances are found to affect actuator performance characteristics, while material selection alone does not affect, provided manufacturing to the required tolerances is possible.

The Effect of Manufacturing Parameters and Environmental Factors on Mechanical Properties of Carbon Fiber/Epoxy Composites

AbstractIn the recent years, the development of wind turbines has been so hectic in Taiwan. The design of the turbine blades directly impacts power effectiveness. In this study, the effects of manufacturing parameters and environmental factors on the mechanical properties of carbon fiber/epoxy composites that are used in turbine blades are discussed. Parameters of the manufacturing process affect the mechanical properties. Carbon composites made by a different numbers of layers are tested on various aspects of performance such as mechanical strength and corrosion resistance.

Inexpensive Apparatus for Fabricating Microspheres for 5-Fluorouracil Controlled Release Systems

The aim of this study was to develop an inexpensive apparatus for fabricating microspheres, based on chitosan, for 5-fluorouracil (5-FU) controlled release. Chitosan microspheres were prepared by precipitation method and the effects of manufacturing parameters (injection and airflow rates) on size distribution microspheres were analyzed by optical and scanning electron microscopy. The results show that the manufacturing parameters, injection and airflow rates, determine the microsphere size distribution. By modulating these parameters, it was possible to produce chitosan microspheres as small as 437 ± 44 μm and as large as 993 ± 18 μm. Chitosan microspheres loaded with 5-FU were also produced using the experimental equipment. The obtained microspheres presented 5-FU controlled release, indicating that the microspheres can be used orally, since they are capable of crossing the stomach barrier and of continuing with the process of 5-FU release.

Effect of manufacturing parameters on mechanical properties of southern yellow pine cross laminated timbers

Development of cross laminated timber (CLT) manufacturing facilities will require an optimization of manufacturing parameters to ensure efficient production. This study examined the effects of press pressure, press time and the addition of water to bond surfaces for a CLT panel composed of southern pine lumber and polyurethane adhesive. Evaluation of the CLT panels used the five-point bending test for bending stiffness, bending strength and shear stiffness in addition to measuring the resistance to shear by compression loading. The shear strength and percent wood failure values obtained from the resistance to shear by compression loading. The optimal combination of manufacturing parameters studied was 100% press pressure and a press time of 80% of the manufacturer recommendations. The addition of water to the bondline surfaces was deemed unnecessary for CLT materials conforming to the PRG-320 standard. Comparison of mechanical properties with Grade V3 showed higher bending strength and shear stiffness values.

The effect of manufacturing parameters on the surface roughness of glass fibre reinforced polymer moulds

The use of Glass Fibre Reinforced Polymer (GFRP) composite moulds has gained considerable attention in composites manufacturing, especially in open-mould processes; owing to several benefits including ease of processing, maintenance as well as low capital cost of tooling. Nevertheless, the surface of GFRP moulds is susceptible to degradation during the composite manufacturing processes which, if not properly maintained, can significantly increase the cost of repairs; and in severe cases, disposal of the mould may be required. In addition, poor surface quality of a mould can directly result in reduced surface finish of the manufactured part. This study, using a systemic design of experiments approach, investigates the effect of select manufacturing process parameters (de-moulding temperature, amount of release agent and environmental storage condition) on the ensuing surface roughness of typical GFRP moulds as used by industry. For this purpose, an open-mould process was simulated whereby a mould/part assembly consisting of top and bottom chopped fiber laminates with gel coat layers, and the release agent between them, was fabricated and subsequently the cured mould/part assembly was de-moulded under both tensile and shear modes. Specimens were tested at different factor combinations and the statistically significant parameters were identified, via analyzing the force values as well as surface roughness measurements on the moulds using White Light Interferometry. Finally, some practical guidelines were sought on the basis of observed individual and interactive effects of parameters.