An Investigation of Electroplastic Drilling of Mild Steel

2017 ◽  
Author(s):  
Brandt J. Ruszkiewicz ◽  
Farbod Akhavan Niaki ◽  
Laine Mears ◽  
Elizabeth Gendreau

Increasing governmental fuel economy requirements drives automakers to increase the fuel economy of their fleets. One of the methods for improving fuel economy is lightweighting vehicles through the use of materials with high strength to weight ratios. Some of these new metals entering the automotive sector are difficult to machine and cause drastically reduced tool life and increase machining cost. It has been shown that electricity has the ability to reduce cutting force during orthogonal cutting and turning. In this research, a design of experiments study on an electrically assisted drilling operation is conducted to determine the impact and interaction between the following input parameters: applied electric current, feedrate, spindle speed, and number of holes cut. These variables used to determine impact and interaction on the following output variables: flank wear, axial cutting force, and temperature evolution. A 2D finite volume method model is used to predict drilling temperature during the process, and is used to aid in predicting axial force. It is found that electric current can reduce cutting force by 10% for 1008 steel at the cost of increased temperature, however, arcing at initial contact causes increased tool wear at higher current inputs.

2013 ◽  
Vol 554-557 ◽  
pp. 2009-2020 ◽  
Author(s):  
Volker Schulze ◽  
Frederik Zanger ◽  
Florian Ambrosy

The present work analyzes the influence of an orthogonal machining process on the generation of nanocrystalline surface layers. Thereby, AISI 4140 is used as work piece material. Metallic parts with a severe nanocrystalline grain refinement in the near-surface area show many beneficial properties. Such surface layers considerably influence the friction and wear characteristics of the work piece in a subsequent usage as design elements working under tribological loads. The focus of this paper is an experimental analysis of a finishing orthogonal cutting operation, carried out with a broaching machine, to generate nanocrystalline surface layers. The influence of process and geometry parameters on the generation of nanocrystalline surfaces is investigated with the aim to massively decrease the grain size in the work piece surface layer. Parameters that are studied and taken into account in the manufacturing process are cutting edge radius rβ, depth of cut h and cutting velocity vc. The cutting edge radius rβ is modified by a drag finishing process. The generation of nanocrystalline surface layers is especially influenced by the design of the uncoated carbide cutting tools. Additionally, cutting force Fc and passive force Fp are determined by a 3-component dynamometer to calculate the relationship between specific cutting force kc and specific passive force kp. The temperature beneath the clearance face is detected by a fiber optic pyrometer. These measurement methods and devices are applied to detect the impact of the most relevant measurement values occurring during machining and causing a drastic reduction of grain size in the surface layer. The evaluation of the manufacturing process is carried out by detailed analyses of the microstructural conditions in the surface layer after processing using a Focused Ion Beam (FIB) system. These material characterizations provide information about the surface engineering concerning the microstructural changes in the surface layer of the work piece due to finishing orthogonal cutting processes.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1340
Author(s):  
Xi Chen ◽  
Dinghua Zhang ◽  
Qi Wang

The cutting force prediction model usually uses the classical oblique transformation method, which introduces the orthogonal cutting parameters into the oblique milling edge shape, and combines the geometric parameters of the tool to convert the orthogonal cutting force into the actual cutting force, thereby predicting the cutting force. However, this cutting force prediction method ignores the impact of tool vibration in actual machining, resulting in a large difference between the prediction model and the actual measurement. This paper proposes a cutting force conversion model considering the influence of the tool system. The proposed model fully considers the impact of tool vibration on the cutting force. On the basis of the orthogonal model, superimposing the additional cutting force generated by tool vibration makes the predicted value of the model closer to the actual cutting force. The results of milling experiments show that the conversion model can obtain higher prediction accuracy. Moreover, compared with the original conversion model, the accuracy of the proposed model is significantly improved.


2016 ◽  
Vol 693 ◽  
pp. 704-709
Author(s):  
Kun Xian Qiu ◽  
Ya Xing Bie ◽  
Sheng Qin ◽  
Qing Long An ◽  
Ming Chen

High strength carbon fiber reinforced polymers (CFRP) with unidirectional laminate structure have gradually developed into major materials in load-bearing aerospace components, and the cutting demand of CFRP is increasing. In this work, orthogonal cutting tests were conducted on T700 high-strength CFRP laminates to get the mechanistic force model of special cutting tools. Also cutting force coefficients were obtained when cutting T700 high-strength CFRP laminates under different fiber orientations. Experimental results showed that the lowest cutting force was obtained when fiber orientation was between 120° and 150°.


2011 ◽  
Vol 148-149 ◽  
pp. 374-379
Author(s):  
Long Bai ◽  
Tao Wang ◽  
Xi Bin Wang ◽  
Jian Jun Chen

The present paper demonstrates a study of the impact of cutting condition on turning high strength steel 34CrNiMo6. Based on Taguchi method, a plan of experiments was performed with ceramic cutting insert. The first and second cutting force equations are developed through the response surface methodology (RSM) to investigate the effect of input cutting parameters (cutting speed, feed rate and depth) on cutting force. In term of input parameters, the cutting force contours are showed and the analysis of the predicted models is performed with aid of the statistical software package. In addition, the separate influence of individual cutting parameter and the interaction between these factors are also discussed in this study. In general, the results obtained from the mathematical model agree well with the experimental data.


Author(s):  
W. T. Donlon ◽  
J. E. Allison ◽  
S. Shinozaki

Light weight materials which possess high strength and durability are being utilized by the automotive industry to increase fuel economy. Rapidly solidified (RS) Al alloys are currently being extensively studied for this purpose. In this investigation the microstructure of an extruded Al-8Fe-2Mo alloy, produced by Pratt & Whitney Aircraft, Goverment Products Div. was examined in a JE0L 2000FX AEM. Both electropolished thin sections, and extraction replicas were examined to characterize this material. The consolidation procedure for producing this material included a 9:1 extrusion at 340°C followed by a 16:1 extrusion at 400°C, utilizing RS powders which have also been characterized utilizing electron microscopy.


2014 ◽  
Vol 84 (5-6) ◽  
pp. 244-251 ◽  
Author(s):  
Robert J. Karp ◽  
Gary Wong ◽  
Marguerite Orsi

Abstract. Introduction: Foods dense in micronutrients are generally more expensive than those with higher energy content. These cost-differentials may put low-income families at risk of diminished micronutrient intake. Objectives: We sought to determine differences in the cost for iron, folate, and choline in foods available for purchase in a low-income community when assessed for energy content and serving size. Methods: Sixty-nine foods listed in the menu plans provided by the United States Department of Agriculture (USDA) for low-income families were considered, in 10 domains. The cost and micronutrient content for-energy and per-serving of these foods were determined for the three micronutrients. Exact Kruskal-Wallis tests were used for comparisons of energy costs; Spearman rho tests for comparisons of micronutrient content. Ninety families were interviewed in a pediatric clinic to assess the impact of food cost on food selection. Results: Significant differences between domains were shown for energy density with both cost-for-energy (p < 0.001) and cost-per-serving (p < 0.05) comparisons. All three micronutrient contents were significantly correlated with cost-for-energy (p < 0.01). Both iron and choline contents were significantly correlated with cost-per-serving (p < 0.05). Of the 90 families, 38 (42 %) worried about food costs; 40 (44 %) had chosen foods of high caloric density in response to that fear, and 29 of 40 families experiencing both worry and making such food selection. Conclusion: Adjustments to USDA meal plans using cost-for-energy analysis showed differentials for both energy and micronutrients. These differentials were reduced using cost-per-serving analysis, but were not eliminated. A substantial proportion of low-income families are vulnerable to micronutrient deficiencies.


Crisis ◽  
2010 ◽  
Vol 31 (5) ◽  
pp. 238-246 ◽  
Author(s):  
Paul W. C. Wong ◽  
Wincy S. C. Chan ◽  
Philip S. L. Beh ◽  
Fiona W. S. Yau ◽  
Paul S. F. Yip ◽  
...  

Background: Ethical issues have been raised about using the psychological autopsy approach in the study of suicide. The impact on informants of control cases who participated in case-control psychological autopsy studies has not been investigated. Aims: (1) To investigate whether informants of suicide cases recruited by two approaches (coroners’ court and public mortuaries) respond differently to the initial contact by the research team. (2) To explore the reactions, reasons for participation, and comments of both the informants of suicide and control cases to psychological autopsy interviews. (3) To investigate the impact of the interviews on informants of suicide cases about a month after the interviews. Methods: A self-report questionnaire was used for the informants of both suicide and control cases. Telephone follow-up interviews were conducted with the informants of suicide cases. Results: The majority of the informants of suicide cases, regardless of the initial route of contact, as well as the control cases were positive about being approached to take part in the study. A minority of informants of suicide and control cases found the experience of talking about their family member to be more upsetting than expected. The telephone follow-up interviews showed that none of the informants of suicide cases reported being distressed by the psychological autopsy interviews. Limitations: The acceptance rate for our original psychological autopsy study was modest. Conclusions: The findings of this study are useful for future participants and researchers in measuring the potential benefits and risks of participating in similar sensitive research. Psychological autopsy interviews may be utilized as an active engagement approach to reach out to the people bereaved by suicide, especially in places where the postvention work is underdeveloped.


2014 ◽  
Vol 1 (2) ◽  
pp. 187
Author(s):  
Serdar KUZU

The size of international trade continues to extend rapidly from day to day as a result of the globalization process. This situation causes an increase in the economic activities of businesses in the trading area. One of the main objectives of the cost system applied in businesses is to be able to monitor the competitors and the changes that can be occured as a result of the developments in the sector. Thus, making cost accounting that is proper according to IAS / IFRS and tax legislation has become one of the strategic targets of the companies in most countries. In this respect, businesses should form their cost and pricing systems according to new regulations. Transfer pricing practice is usefull in setting the most proper price for goods that are subject to the transaction, in evaluating the performance of the responsibility centers of business, and in determining if the inter-departmental pricing system is consistent with targets of the business. The taxing powers of different countries and also the taxing powers of different institutions in a country did not overlap. Because of this reason, bringing new regulations to the tax system has become essential. The transfer pricing practice that has been incorporated into the Turkish Tax System is one of the these regulations. The transfer pricing practice which includes national and international transactions has been included in the Corporate Tax Law and Income Tax Law. The aim of this study is to analyse the impact of goods and services transfer that will occur between departments of businesses on the responsibility center and business performance, and also the impact of transfer pricing practice on the business performance on the basis of tax-related matters. As a result of the study, it can be said that transfer pricing practice has an impact on business performance in terms of both price and tax-related matters.


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