scholarly journals Comparison of Flank Super Abrasive Machining vs. Flank Milling on Inconel® 718 Surfaces

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1638 ◽  
Author(s):  
Haizea González ◽  
Octavio Pereira ◽  
Asier Fernández-Valdivielso ◽  
L. López de Lacalle ◽  
Amaia Calleja
Keyword(s):  
Residual Stresses ◽  
White Layer ◽  
Added Value ◽  
New Technique ◽  
Flank Milling ◽  
Manufacturing Processes ◽  
Abrasive Machining ◽  
Conventional Process ◽  
Controllable Process

Thermoresistant superalloys present many challenges in terms of machinability, which leads to finding new alternatives to conventional manufacturing processes. In order to face this issue, super abrasive machining (SAM) is presented as a solution due to the fact that it combines the advantages of the use of grinding tools with milling feed rates. This technique is commonly used for finishing operations. Nevertheless, this work analyses the feasibility of this technique for roughing operations. In order to verify the adequacy of this new technique as an alternative to conventional process for roughing operations, five slots were performed in Inconel® 718 using flank SAM and flank milling. The results showed that flank SAM implies a suitable and controllable process to improve the manufacture of high added value components made by nickel-based superalloys in terms of roughness, microhardness, white layer, and residual stresses.

Experimental and numerical analyses of residual stresses induced by tube drawing

2018 ◽  
Vol 53 (5) ◽  
pp. 364-375
Author(s):  
Florian Vollert ◽  
Marco Lüchinger ◽  
Simone Schuster ◽  
Nicola Simon ◽  
Jens Gibmeier ◽  
...  
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Fuel Efficiency ◽  
Carbon Dioxide Emission ◽  
Medium Carbon Steel ◽  
Hole Drilling ◽  
Manufacturing Processes ◽  
Drawing Process ◽  
Tube Drawing ◽  
Hole Drilling Method

Lightweight constructions are used to fulfil the ever-increasing demands regarding fuel efficiency and carbon dioxide emission in transportation industries. In order to reduce weight, technical components made of solid materials are often replaced by tubular structures. Under service conditions, the components are frequently exposed to cyclic loads. Hence, residual stresses that are induced by manufacturing processes can have a significant impact on service life. In this work, the focus is on tube manufacturing processes, precisely cold tube sinking and fixed plug drawing. Both processes induce characteristic residual stress states, which are important to assess the mechanical integrity and load-carrying capacity of tubular components during service. The aim of this article is to examine the residual stress depth distribution for medium-carbon steel tubes manufactured by cold tube sinking and fixed plug drawing. The residual stresses are measured by means of the Sachs method and the hole-drilling method, respectively. The measured results are compared to finite element simulations of the tube drawing process. It is shown that the residual stress obtained with the different experimental methods and the numerical simulations are consistent. Furthermore, it is shown that the residual stresses can be significantly reduced when a plug is used in the drawing process.

scholarly journals A New Technique for Improved Use of Thermal Energy from Waste Effluents

Agronomy ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 97
Author(s):  
José Manuel Magide-Ameijide ◽  
Hiram Varela-Rodríguez ◽  
Adolfo López-Fabal
Keyword(s):  
Energy Efficiency ◽  
Organic Fertilizer ◽  
Industrial Applications ◽  
Added Value ◽  
New Technique ◽  
Industrial Processes ◽  
Waste Energy ◽  
Waste Effluents ◽  
A New Technique ◽  
Process Fluid

Energy sustainability and environmental protection in general are at the heart of engineering and industry discussions. Countless efforts have been devoted to improving the energy efficiency of industrial processes and specifically to harnessing their waste energy sources. One such source is waste from agro-industrial processes, which is frequently characterized by increased temperatures and high polluting potential. There are multiple available choices for exploiting energy from such waste, but this paper proposes a new alternative technique that substantially improves the efficiency. Based on the technology of leveraging a hot liquid effluent for heating a process fluid, this system introduces a third liquid to be revalorized by drying that is placed in between the hot and cold liquids. By adding stirrers inside the heat exchanger, the thermal resistance of the third fluid is reduced to a negligible level. Thus, this system has almost the same advantages as the previous one, but with the added benefit that it allows drying of a third fluid. One of the specific applications of this proposed technology is using heat from waste effluents to obtain dried food products. In the present work, it was used to dry slaughterhouse blood to obtain so-called “blood meal”, a product with a high added value that is used as pet food or organic fertilizer, and also has many other industrial applications. As shown here, the new technique outperforms existing alternatives in terms of energy efficiency and economic profitability.

Residual Stress in Plain Carbon Steel Induced by Laser Hardening

2015 ◽  
Vol 812 ◽  
pp. 321-326 ◽  
Author(s):  
A. Filep ◽  
Márton Benke ◽  
Valéria Mertinger ◽  
Gábor Buza
Keyword(s):  
Heat Transfer ◽  
Residual Stress ◽  
Residual Stresses ◽  
Plain Carbon Steel ◽  
Laser Hardening ◽  
Manufacturing Processes ◽  
Stress Profile ◽  
Multiple Sources ◽  
Residual Stress Profile ◽  
Hardening Treatment

Technological residual stresses have great importance in the manufacturing processes and the lifetime of components. The residual stresses formed by quenching can be very diverse because of its multiple sources. Alternative quenching processes such as laser hardening have a great potential for different applications. The direction of heat transfer during laser hardening is the opposite compared to conventional quenching. This further increases the complexity of the developed stress state. The residual stress profile and the microstructure formed by laser hardening treatment are investigated in the present manuscript.

Analysis of Surface Integrity for DIN 100Cr6 Steel Conical Bearing Rings after Hard Turning

2011 ◽  
Vol 223 ◽  
pp. 473-482 ◽  
Author(s):  
Sergio Delijaicov ◽  
Carlos Eddy Valdez Salazar ◽  
Éd Claudio Bordinassi ◽  
Linilsson Rodrigues Padovese
Keyword(s):  
Tool Wear ◽  
Residual Stresses ◽  
Hard Turning ◽  
White Layer ◽  
Cutting Speed ◽  
Hole Drilling ◽  
Machining Parameters ◽  
Hole Drilling Method ◽  
Conical Bearing ◽  
Bearing Rings

This work studies the influence of machining parameters, such as cutting speed and forces, feed rate, cutting depth, and tool flank wear, on the generation of surface residual stresses in DIN 100Cr6 steel conical bearing rings submitted to a hard turning process. A complete factorial planning was used to perform the tests and projected measurement. Cutting forces were measured by a piezoelectric dynamometer and residual stresses were determined by the hole-drilling method using strain gage. Results showed that after 2000 m of tool machining, phase transformations had been observed on sample surfaces, with white layer formation, and deeper, a dark layer whose thickness varied depending on the severity level of turning and the tool wear (in machined distance). Increase in tool wear generated minor values of compressive residual stresses and the surface roughness presented almost the same values in all experiments, except when the bigger parameters were used.

scholarly journals Costs Analysis of Iron Casts Manufacturing

2012 ◽  
Vol 12 (2) ◽  
pp. 45-48 ◽  
Author(s):  
S. Kukla
Keyword(s):  
Added Value ◽  
Manufacturing Processes ◽  
Production Flow ◽  
Pareto Analysis ◽  
Costs Analysis ◽  
Constant Improvement ◽  
Plant Transport

Costs Analysis of Iron Casts Manufacturing The article presents the issues of costs analysis of iron casts manufacturing using automated foundry lines. Particular attention was paid to departmental costs, conversion costs and costs of in-plant transport. After the Pareto analysis had been carried out, it was possible to set the model area of the process and focus on improving activities related to finishing of a chosen group of casts. In order to eliminate losses, the activities realised in this domain were divided into activities with added value, activities with partially added value and activities without added value. To streamline the production flow, it was proposed to change the location of workstations related to grinding, control and machining of casts. Within the process of constant improvement of manufacturing processes, the aspect of work ergonomics at a workstation was taken into account. As a result of the undertaken actions, some activities without added value were eliminated, efficiency was increased and prime costs of manufacturing casts with regard to finishing treatment were lowered.

scholarly journals Utilização da técnica de difração de raios-X para o estudo de amostras de Ti-6Al-4V forjadas e fabricadas por fusão seletiva a laser

2019 ◽  
Vol 40 ◽  
pp. 249
Author(s):  
Max Amorim Brum ◽  
Fábio Beck ◽  
Oreci Escobar da Silva ◽  
Gustavo Luiz Callegari ◽  
Marcos André Carara ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Selective Laser Melting ◽  
Structural Characteristics ◽  
Lattice Parameter ◽  
Manufacturing Processes ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
Engineering Project ◽  
X Ray ◽  
Great Relevance

The search for materials with well-defined characteristics is very important for any engineering project. In addition, it is known that the various types of manufacturing processes directly influence in properties of the parts. In this work, the X-ray diffraction technique was used to study the structural characteristics of Ti-6Al-4V samples manufactured by the forging and Selective Laser Melting techniques. We found that the samples made by FSL were able to present a reduction of 1% in the lattice parameter perpendicular to the studied plane, when compared with the forged samples. Since most of the parts manufactured by Selective Laser Melting meet the demands of aeronautical and aerospace projects, where residual stresses are generally undesirable for making the parts more fragile, studies like these acquire great relevance.

scholarly journals Study on the origins of residual stresses in Ti-6Al-4V processed by additive manufacturing

2020 ◽  
Vol 321 ◽  
pp. 03001
Author(s):  
Nathan Dumontet ◽  
Benoit Malard ◽  
Bernard Viguier
Keyword(s):  
Additive Manufacturing ◽  
Energy Density ◽  
Residual Stresses ◽  
Dwell Time ◽  
Scanning Speed ◽  
Manufacturing Processes ◽  
Thermal Gradients ◽  
Laser Beam Melting ◽  
Reliable Parameter ◽  
Stress States

In additive manufacturing processes using laser beam melting high thermal gradients are generated, inducing residual stresses within the parts that may lead to deformations and, in worst cases, cracks. One of the materials that is the most sensitive to residual stresses is the Ti-6Al-4V alloy. In the present study, we focus on the various parameters that may control the genesis and build-up of the residual stress states. Dwell time and thermal conductivity, both influencing the heat evacuation, were studied. Higher thermal evacuation was find to rises residual stresses within the part. Then, the reliability of the energy density as a comparison parameter was investigated. Samples with the same energy densities but different power and scanning speed were elaborated. Energy density was shown as a non-reliable parameter to compare different processed parts.

Study on the Effect of Grinding Parameters to the White Layer Formation in Grinding SKD-11 Hardened Steel

2008 ◽  
Vol 53-54 ◽  
pp. 279-284 ◽  
Author(s):  
Wei Wei Ming ◽  
Qing Long An ◽  
Ming Chen
Keyword(s):  
Rapid Heating ◽  
White Layer ◽  
Ground Surface ◽  
Hardened Steel ◽  
Manufacturing Processes ◽  
Layer Formation ◽  
Machined Surface ◽  
Variable Parameters ◽  
Die Steel ◽  
White Layer Formation

White layer formed in the machined surface has been observed in many manufacturing processes. However, grinding has been considered more sensitive to form white layer due to the characteristics with high temperature and rapid heating and quenching. As an effective process to the difficult-to-machining die steel, grinding is widely used in the finishing of die and mould components with high precision. So study on white layer formed in ground surface is significant to improve the product quality and life. In this paper, grinding experiments focus on SKD-11 hardened steel with variable parameters were conducted to study the white layer formation and the parameter optimization to develop the favorable white layer and restrict the thickness of the dark-etching layer and the hot-affective region.

Effects of Process Parameters on White Layer Formation and Morphology in Hard Turning of AISI52100 Steel

2016 ◽  
Vol 138 (7) ◽  
Author(s):  
Xiao-Ming Zhang ◽  
Li Chen ◽  
Han Ding
Keyword(s):  
Heat Treatment ◽  
Residual Stresses ◽  
Hard Turning ◽  
White Layer ◽  
Cutting Speed ◽  
Layer Formation ◽  
Bulk Materials ◽  
Medium Temperature ◽  
White Layer Thickness ◽  
White Layer Formation

Hard turning is becoming increasingly considered by industry as a potential substitute for grinding. However, it is greatly hurdled by surface integrity problems such as tensile residual stress and white layer, which are generally found to have negative effects on the stress corrosion, wear resistance, and fatigue life of the machined parts. This paper investigates white layer formation and morphology in hard turning process using various process parameters, taking into account the effects of heat treatment which results in microstructure and hardness differences on bulk materials. Samples undergone three typical heat treatment processes are prepared and then machined using different cutting speeds and radial feed rates. Optical microscope, scanning electron microscope (SEM), and X-ray diffraction (XRD) are employed to analyze the microstructures of white layer and bulk materials after varies heat treatments and cutting processes. Through the studies, we find the existence of a cutting speed threshold, below which no white layer forms for both the low and medium-temperature tempering. The threshold value increases; however, the white layer thickness decreases under the same cutting conditions, for the low and medium-temperature tempering, respectively. Also, we find that the white layer thickness and the scattering of it along the cutting direction on the surface increases with cutting speed and radial feed rate. White layer with wavy morphology can be found in samples after quenching at high cutting speed. We first discover that the pitch of the white layer with wavy morphology is similar to the displacement of tool at the time a segment of the serrated chips forms. Also, the surface residual stresses of the samples are measured. Relationship between white layer and residual stresses is presented. Based on the relationship we reveal that high temperature is more dominant than volume expansion for white layer formation.

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