Secondary Manufacturing Processes Research Articles

Statistical analysis on the influence of drilling parameters on GFRP-PUF sandwich composite structure

ABSTRACT Composite sandwich structures are finding increasing applications in various fields and industries such as aerospace, automotive, acoustics and so on due to their high strength-to-weight ratio and better insulation properties. To facilitate the assembly of these structures, fasteners are employed, and drilling is one of the secondary manufacturing processes that can produce cost-effective and good-quality holes for fastening. This paper deals with characterising the quality of the drilled holes in glass fibre-reinforced plastic-polyurethane foam sandwich structures. This experiment has been designed using Taguchi’s L9 orthogonal array. The results indicate that smaller drill diameter and lower feed rate produce delamination of lower magnitude at entry and exit while higher spindle speeds followed by lower feed rates produced holes with minimal deviation from the ideal form.

Resonant ultrasound spectroscopy of hybrid metal additive manufacturing

Additive manufacturing has been targeted as the next high-impact fabrication technique for parts and components. Hybrid metal additive manufacturing (AM) refers to the 3-D printed fabrication process involving secondary manufacturing processes or energy sources and multifunctional printing. Specific layers are altered within the build using additional processes (i.e., milling or peening) that are synergistic with the additive process. This combination alters the sample microstructure and can refine grains, increase dislocation density, or induce residual stresses. The effect of these hybrid layers is typically not confined within the layer alone but has a compounding effect on preceding layers. The goal is to control the changes in print parameters throughout the build to enhance component performance, but unique challenges remain for nondestructive validation of such samples. Traditional ultrasonic methods on hybrid-AM components have successfully mapped material variations with sufficient spatial resolution. However, the use of resonance ultrasound spectroscopy (RUS) for hybrid-AM is less developed. In this presentation, the use of RUS is described relative to the characterization of hybrid AM 316L stainless steel samples. The spatial organization of the hybrid samples affects the resonances relative to their mode shape. Computational models are used to quantify the impact of the hybrid processes.

A RETROSPECTIVE ANALYSIS ON DRILLING OPERATION AND ITS PARAMETERS: A CRITICAL REVIEW

Primary manufacturing processes like casting, forming, and shaping (forging, rolling, drawing, extrusion, sheet forming, and molding) further need any of the secondary manufacturing processes like turning, drilling, boring, planing, milling, grinding, etc. In order to produce superior quality products, and to enhance productivity, the selection of desirable process parameters is significant. The selection of suitable process parameters is essential for accomplishing the desired component. Based on the existing literature, this study examines the causes, effects, and variances regarding chip formation, tool geometry, thrust force, torque, surface roughness, drilling time, and other drilling quality characteristics in the most typical machining operations such as drilling. Developing a repository on these process parameters will guide the process planning engineer for ready reckon. Therefore, this work aims at the development of a detailed repository with the study of characteristics. Further, this literature review comprehends the characteristics of a behavior with its reasoning, which was detailed in the past decade. It reveals the beneficial process parameters for achieving better production rate and superior quality.

Adding Value to Secondary Aluminum Casting Alloys: A Review on Trends and Achievements.

Aluminum is a critical element of the circular economy as it can be recycled several times. Moreover, Al recycling is a more economically and environmentally efficient procedure than the primary Al production from ores. Secondary aluminum alloys are mostly used in casting applications since it is possible to accommodate their chemical composition through secondary manufacturing processes. However, the quality of the alloys may be considerably altered during the different steps of the recycling process. Inadequate waste sorting might result in excessive contamination. Iron is the most dangerous contaminant because it causes brittle and fragile intermetallic phases, which significantly impacts the mechanical characteristics of alloys. In addition, the microstructure of the alloy changes significantly after multiple cycles of remelting. These issues lead to the downcycling of aluminum, i.e., in other words, the reduction in the overall quality of the alloys. Thus, it has been shown that a number of procedures, including ultrasonic melt treatment and microalloying with rare earths, can somewhat alter the shape of the Fe-rich phases in order to reduce the shortcomings of downcycling. However, a solid mechanical characterization is still missing in order to improve the Fe-rich phase alteration.

Ultrasonic Welding of Banana/ Bagasse Based Polypropylene Composites

ABSTRACT The usage of natural fiber–reinforced composites (NFRCs) may help the global fraternity in achieving their long-term goal of developing sustainable products having minimum effect on ecosystem, during and at the end of their service life. The primary manufacturing processes such as injection molding, hand-layup, and compression moulding have been extensively used to fabricate products with simpler profiles. However, the fabrication of complex products necessitates secondary manufacturing processes. In current investigation, the short fiber (banana and bagasse)–based polypropylene composites (10, 15, and 20 wt.%) were fabricated using extrusion-injection moulding process. Banana fiber–based composites recorded 1.8%, 4.7%, and 3.25%, higher tensile strength than bagasse fiber–based composites at 10, 15, and 20 wt.% fiber loading, respectively. However, bagasse fiber–based composites performed distinctly better in flexural properties. Field emission scanning electron microscopy and thermogravimetric analysis were employed to analyze the failure mechanisms and thermal degradation behavior (analyzed at 5%, 25%, 50%, and 75% weight loss) of the fabricated composites. The ultrasonic welded joints of banana fiber–based composites recorded higher failure load prior to the fracture as compared to bagasse fiber–based composites upto 15% fiber loading. It was established that ultrasonic welding can be successfully employed for joining of NFRCs.

Design and fabrication of remote-controlled seed sowing machine

In most countries of which Nigeria is among, Agriculture plays a very vital role in their economic growth. Agriculture is one of the backbones of Nigeria's economy among oil production. It is on this note that farmers are given all the necessary assistance to boost their production. These include provision of good and improved seeds and seedlings, fertilizers and improved implements/equipment for clearing, planting and harvesting to increase their yield. This research work involves the design and fabrication of remote controlled seed sowing machine to assist local or peasant farmers in seed sowing, thus reducing stress and time wastage involved in the primitive way of planting. A review of the seed sowing machine was conducted. A design concept was developed and the detailed design was carried out. The machine was manufactured using the secondary manufacturing process and tested for performance. The result showed that the control range of 10m was achieved, the machine can also cover 1000 square meter in 5 minutes and its efficiency is 95 percent.

Processing and rheological behavior of cross‐linked polyethylene containing disulfide bonds

AbstractVitrimers are a new class of materials that consist of chemically cross‐linked networks that engage in thermoactivated associative exchange reactions. These exchange reactions can impart malleability, healing, and recyclability properties to thermosets. In this study, a one‐step protocol to prepare linear low‐density polyethylene (LLDPE) vitrimer‐like materials with disulfide exchange bonds via reactive blending is presented. The cross‐linking reaction of maleic anhydride‐grafted‐linear low‐density polyethylene (LLDPE‐MAH) and 4,4′‐dithiodianiline was followed in a torque rheometer. The degree of MAH‐functionalization and its impact on the melt rheology, dynamic mechanical properties, and thermal properties of the vitrimer was studied. The cross‐linked LLDPE possessed a mostly elastic behavior, with storage modulus () higher than loss modulus () in the entire frequency range. The complex viscosity of cross‐linked LLDPE at high frequencies (>100 rad/s) was comparable to the thermoplastic LLDPE. The MAH‐groups and formation of cross‐links decreased the degree of crystallinity, which led to a decrease in the storage modulus at a temperature of 35°C. The storage modulus and dimensional stability of the materials improved with cross‐linking density, suggesting potential benefits of LLDPE vitrimers in secondary manufacturing processes. Finally, the reprocessing ability was demonstrated via internal mixing and the rheological and mechanical properties were retained.

Utilization of induction furnace steel slag based iron oxide nanocomposites for antibacterial studies

Metals and metal oxide-based nanocomposites play a significant role over the control of microbes. In this study, antibacterial activity of iron oxide (Fe2O3) nanocomposites based on induction furnace (IF) steel slag has been carried out. IF steel slag is an industrial by-product generated from secondary steel manufacturing process and has various metal oxides which includes Al2O3 (7.89%), MnO (5.06), CaO (1.49%) and specifically Fe2O3 (14.30%) in higher content along with metalloid SiO2 (66.42). Antibacterial activity of iron oxide nanocomposites has been revealed on bacterial species such as Micrococcus luteus, Bacillus subtilis and Staphylococcus aureus. Micrococcus luteus has undergone maximum zone of inhibition (ZOI) of 12 mm for 10 mg/mL concentration of steel slag iron oxide nanocomposite. Growth inhibitory kinetics of bacterial species has been studied using ELISA microplate reader at 660 nm by varying the concentration of steel slag iron oxide nanocomposites. The results illustrate that IF steel slag is a potential material and can be utilized in building materials to increase the resistance against biodeterioration.Graphic abstract

Squeeze Cast Mg-Zn Alloys for Bioapplications: Tensile Properties and Microstructure

In the past, Mg-Zn alloys prepared by a two-step manufacturing process of casting plus extrusion have been demonstrated to be a good candidate for biodegradable applications. But, studies on fabricating of Mg-Zn alloys with a single step process of squeeze casting capable of producing porosity-free Mg alloys, which can reduce the cost, are limited. In the present work, Zinc (Zn) addition varying from 1.0 up to 10.0 wt. % was introduced into liquid magnesium. The alloyed liquid was squeeze cast under an applied pressure of 90 MPa. The results of mechanical testing on the squeeze cast Mg-Zn alloys shows that Zn is an effective additive for enhancing their mechanical properties, specifically, tensile and yield strengths at room temperature, but reducing the elongation. While the Zn addition rises from 1.0 to 10.0 wt.%, the ultimate tensile and yield strengths increases to 181.0 MPa and 105.0 MPa from 140.7 MPa and 39.3 MPa, while the elongation-to-failure (ef) decreases to 3.7% from 6.2%, respectively. The reveal of the as-cast grain structure by an optical microscope (OM) indicates that the high Zn content reduces grain sizes considerably. The microstructures analyzed by a scanning electron microscope (SEM) with the energy dispersive spectroscopy (EDS) show that the secondary MgZn phase forms once Zn is introduced in sufficient amount. The grain refinement and the massive presence of the secondary MgZn phase at the boundaries of the refined grains should be responsible to the enhancement of the strengths and the reduction in the elongation. The developed pressurized casting without employing secondary manufacturing processes such as extrusion or heat treatment exhibits its advantages to enhance the mechanical properties of the Mg alloys with high Zn content over conventional fabrication processes, since high Zn-containing Mg alloys have a long freezing range and tend to form microshrinkage porosity.

Synthesis and Mechanical Property Evaluation of Hot Forged Aluminium Alloy Reinforced with Nano Alumina

Metal matrix composites with aluminium matrix and non-metallic reinforcements are popular candidates in automotive, aerospace, sports and military application because of their high strength-to-weight ratio, stiffness, wear resistance, high-temperature resistance, etc. often they are subjected to secondary manufacturing processes like extrusion, rolling, forging, etc. to suit the service requirements. Metal matrix composites reinforced by nanoparticles are very promising materials, suitable for a large number of applications. In the present investigation, nanocomposites have been synthesized by addition of 0.25, 0.5, 0.75, 1 and 1.25 wt% of nanoAl2O3 powder in to molten Al 1100-Mg alloy using stir casting method and then hot forged. The mechanical properties such as tensile strength, hardness and percentage elongations were studied for all the test specimens. The 0.75 wt% of nanoAl2O3 added forged nanocomposite exhibited higher hardness and 0.5 wt% of nanoAl2O3 added forged nanocomposite exhibited higher yield strength, tensile strength and percentage of elongation.

Improving Powder Characteristics by Surface Modification Using Atomic Layer Deposition

The particulate properties of a material after primary manufacturing have a large impact on the secondary manufacturing processes. Especially, powder characteristics leading to poor flowability are...

Logistic regression model for the grooving process of hybrid polyester resin composite materials reinforced with natural fibers and fiberglass

Greencomposites materials are being integrate into the manufacturing of products in diverse fields. For its assembly, are required secondary manufacturing processes such as the machining of slots and holes. In these processes, the greencomposites present great sensitivity to their manufacture. For the study of this concept, an experimental design was developed to analyze the grooving process and verify the effects of the cutting parameters with two types of tools (HSS and HSC) on surface quality (Ra) and the delamination factor (Fd) of the material. An analysis of the experiment was carried out to verify the significant effects of the different factors involved, in addition a multiple linear regression analysis and binomial logistic regression to predict surface quality and delamination in other conditions. The results obtained show the logistic regression model gave a better prediction for the grooving process of the greencomposites, both for the surface roughness and for the delamination factor. Finally, this study concludes that the carbide tool (HSC) has better surface quality with respect to the conventional tool of high speed steel (HSS).

Microstructure and mechanical property connections for a punched non-oriented electrical steel lamination

Secondary manufacturing processes used on electrical steels, such as mechanical or laser cutting, have a detrimental effect on the magnetic properties and increase the losses for electric motors. When the process is mechanical, there is both work hardening, and residual stress induced near the cut edge. The knowledge of the type of deterioration near the cut edge and the degree of deterioration is important for designing electrical machines in terms of magnetic field and loss calculations. The present paper evaluates the effect of punching on the microstructure and mechanical properties of non-oriented electrical steel. Scanning Electron Microscopy (SEM) and Electron backscattered diffraction (EBSD) analysis was performed on the cross section of the punched non-oriented electrical steel to study the evolution of microstructure and crystallographic texture near the edge whereas nanoindentation was used to determine the hardness profile. The observed mechanical properties were related to the microstructure near the edge, which was highly heterogeneous. The microstructure of the punched steel consisted of elongated grains and shear bands with ultrafine grains of size smaller than 500 nm. The hardness was maximum in a region where shear bands were observed in the punched microstructure and the value obtained was 4.54 GPa. This hardness increase, with respect to the average hardness of undamaged steel (3.15 GPa), was attributed to various factors such as grain refinement, work hardening and residual stress. Finally, pop-in analysis was done to study the extent of work hardening due to punching and its effect on hardness. The zero pop-in region was extended to a distance of 200 µm from the edge in the fracture section whereas it was 50 µm in roll over section.

The effect of cutting parameters on cutting force and tool wear in machining Nickel Titanium Shape Memory Alloy ASTM F2063 under Minimum Quantity Nanolubricant

The nickel-titanium (NiTi) shape memory alloys have drawn substantial interest among research communities and industries due to their superior properties in shape memory effect and super-elasticity as compared to the typical alloys and super-alloys. The use of this material in biomedical applications has now been widely recognized and accepted due to its biocompatibility to human body. For instance, NiTi alloys under the ASTM F2063 classification are often applied in medical devices and surgical implant applications. However, due to their poor thermal conductivity and high strain or work hardening effects, a number of complications arise when secondary manufacturing processes such as machining are carried out on these alloys. The use of appropriate coolant technology should be able to overcome these problems through effective cooling and lubricating near the cutting zone. In the present study, the influences of machining parameters, namely; cutting speed, feed rate and depth of cut, on the cutting forces and tool wear have been investigated under two modes of cutting environment, namely, dry and minimum quantity nanolubricants. The results show that minimum quantity nanolubrication with aluminium oxide nanoparticles leads to a notable effect in alleviating the amount of tool wear and at the same time controlling the development of cutting force. The reduction in the cutting force and tool wear while applying the minimum quantity nanolubricants is approximately 6-10% and 4-30%, respectively; as to that of dry cutting. It was also observed that the main mechanisms of wear for all conditions are mainly abrasion on the flank face of the cutting inserts. As a whole, the lubrication approach suggested in this study is an effective strategy to reduce ecological impacts and offer cost effective alternative for machining these unique alloys.

Measurement of surface characteristics of Ti6Al4V aerospace engineering components in mass finishing process

Mass finishing is a secondary manufacturing process employed in aerospace and automotive industries to obtain the required surface finish of engineering parts. The finishing process involves interaction of several input process parameters related to the finishing machine, abrasive media and the parts to be finished. A robust empirical model which can accurately predict the system behavior and capture the science of complex interactions between process variables would provide great insights on mass finishing process. To address this challenge, the authors have proposed a novel integrated data analytics model by combining two powerful evolutionary techniques, Gene Expression Programming and Adaptive Neuro-Fuzzy Inference system. The proposed integrated approach was able to capture the dynamics of mass finishing process more accurately compared to that of other commonly available data analytical models. Tribological analysis of the model showed that an optimal surface finish of mass finished part can be achieved in mass finishing process by regulating the process time and media type. It is anticipated that the proposed model can be useful for determining optimal parameters for achieving desired surface finish without the need to conduct experiments, thereby leading to considerable savings in materials and time.

Evaluation of Resource Efficient Process Chains for Secondary Manufacturing Processes of Bamboo Bicycles

In order for manufacturing suppliers to stay competitive in the global market, innovative and resource efficient process chains need to be a part of the manufacturing strategy. Secondary manufacturing process steps entail the assembly and surface treatment manufacturing steps after the primary cutting and shaping of the components. Bicycles have an enormous effect on society, both in terms of socio-economics and of advancing modern industrial processes. In order to manufacture bamboo bicycle frames in South Africa innovative designs and process chains need to be developed. In this study process chains for secondary manufacturing processes of bamboo bicycles were developed and compared. The manual secondary process steps for manufacturing bamboo bicycles in Africa were mapped and compared with developed technological process chains in terms of resource efficiency. The effect on time and cost were evaluated.

Sustainably Manufacturing a Bamboo Bicycle in a Container Factory

In order for manufacturing suppliers to stay competitive in the global market, innovative and resource efficient process chains need to be a part of the manufacturing strategy. Secondary manufacturing process steps entail the assembly and surface treatment manufacturing steps, after the primary cutting and shaping of the components. Bicycles have an enormous effect on society, both in terms of socio-economics and of advancing modern industrial processes. In order to manufacture bamboo bicycle frames in South Africa, innovative designs and process chains need to be developed. Container factories could be the answer to reduce costs and increase resource efficiency. In this study, the feasibility of manufacturing bamboo bicycle in shipping containers is investigated. These results are then used to evaluate the sustainability of manufacturing bamboo bicycles in container factories.

Multi-Objective Optimization of Squeeze Casting Process using Genetic Algorithm and Particle Swarm Optimization

Abstract The near net shaped manufacturing ability of squeeze casting process requiresto set the process variable combinations at their optimal levels to obtain both aesthetic appearance and internal soundness of the cast parts. The aesthetic and internal soundness of cast parts deal with surface roughness and tensile strength those can readily put the part in service without the requirement of costly secondary manufacturing processes (like polishing, shot blasting, plating, hear treatment etc.). It is difficult to determine the levels of the process variable (that is, pressure duration, squeeze pressure, pouring temperature and die temperature) combinations for extreme values of the responses (that is, surface roughness, yield strength and ultimate tensile strength) due to conflicting requirements. In the present manuscript, three population based search and optimization methods, namely genetic algorithm (GA), particle swarm optimization (PSO) and multi-objective particle swarm optimization based on crowding distance (MOPSO-CD) methods have been used to optimize multiple outputs simultaneously. Further, validation test has been conducted for the optimal casting conditions suggested by GA, PSO and MOPSO-CD. The results showed that PSO outperformed GA with regard to computation time.

Micro-indentation based study on steel sheet degradation through forming and flattening: Toward a predictive model to assess cold recyclability

Sheet metal forming has always been an important sector of the metal industry thanks to work hardening, however, a complex set of deformation entails evolution of damage in the material through the forming stages. With an outlook to cold recycling of sheet metals, this paper focuses on experimental quantification of damage and degradation in load carrying capacity due to the forming process. Assuming that cold recycling of sheet metals involves an intermediate flattening prior to the secondary forming process, the adverse effects of flattening on the material was also investigated. An industrial cold roll forming process was taken as case study. An experimental investigation using microhardness mapping on the cross-section of fold zones, in conjunction with 3D global-local FE modelling, were the basis of through-thickness damage analysis. Taking advantage of strain-hardness correlation a new method was established to extrapolate hardness for ductile damage characterization. Investigation on sensitivity of the measured microhardness to crystallographic texture and sample surface preparation backed the experimental results. The results particularly outlined the progressive decrease in load carrying capacity of material after forming and after flattening. The possibility of a secondary manufacturing process is discussed.

Avaliação microbiológica de queijo do Marajó tipo creme, de leite de búfala, elaborado em queijarias da Ilha do Marajó, Pará

O Queijo do Marajó, obtido a partir do leite de búfala, representa uma importante atividade econômica no Estado do Pará, em especial na Ilha do Marajó, no qual vigora a produção de forma artesanal. Este trabalho tem como objetivo avaliar a qualidade microbiológica do Queijo do Marajó, tipo creme, de leite de búfala, elaborados em duas queijarias localizadas na Ilha do Marajó, Pará, a fim de verificar se os derivados encontram-se em condições microbiológicas e higiênico-sanitárias adequadas. Foram realizadas análises microbiológicas de Coliformes Totais, Coliformes Termotolerantes, Staphylococcus aureus, contagem padrão de bactérias aeróbias mesófilas, e contagem de fungos filamentosos e leveduras. Todas as análises seguiram a metodologia descrita na Instrução Normativa nº 62, de 26 de Agosto de 2003, do Ministério da Agricultura, Pecuária e Abastecimento. As médias dos resultados microbiológicos mostraram que as amostras de queijo das duas queijarias avaliadas não apresentaram contaminação por nenhum dos micro-organismos analisados, estando assim de acordo com o Regulamento Técnico de Produção do Queijo do Marajó, Portaria nº 418, de 04/03/2013. Diante dos resultados obtidos, pode-se verificar a importância de cuidados de higiene no processo de fabricação do derivado, e que o tratamento térmico utilizado nas etapas de elaboração, também contribuiu para garantir a qualidade do produto final.Palavras-chave: qualidade, Marajó, búfala