scholarly journals Micro-Slit Cutting in an Aluminum Foil Using an Un-Traveling Tungsten Wire

2020 ◽  
Vol 10 (2) ◽  
pp. 665
Author(s):  
Jiacheng Zhu ◽  
Xiaolong Fang ◽  
Ningsong Qu
Keyword(s):  
Surface Roughness ◽  
Standard Deviation ◽  
Tungsten Wire ◽  
Feeding Rate ◽  
Aluminum Foil ◽  
Optimal Parameters ◽  
Cutting Mechanism ◽  
Average Width ◽  
Series Of Experiments ◽  
Secondary Velocity

Microslit cutting in aluminum foils is considered to be difficult as aluminum foils have low hardness and deformability. In this study, a novel cutting method is proposed where a tungsten microwire is utilized as the tool to cut aluminum foil without tool traveling or spinning. A statics simulation is first performed to analyze the cutting mechanism. Further, a tungsten wire with a diameter of 50 μm is utilized as the tool and a series of experiments are carried to discuss how the feeding rate influences slit width and roughness. With optimal parameters, it takes only 100 s to fabricate a 5 mm long microslit with an average width of 48.75 μm, width standard deviation of 1.48 μm, and surface roughness of 0.110 μm when applying initial/secondary velocity of 50/50 μm·s−1.

Optimal parameters of abrasive flow finishing for hip joint implants

2021 ◽  
pp. 095440542199561
Author(s):  
Yahya Choopani ◽  
Mohsen Khajehzadeh ◽  
Mohammad Reza Razfar
Keyword(s):  
Surface Roughness ◽  
Standard Deviation ◽  
Femoral Head ◽  
Hip Joint ◽  
Spherical Shape ◽  
Shape Deviation ◽  
Head Surface ◽  
Joint Implants ◽  
Finishing Processes ◽  
Abrasive Flow Finishing

Total hip arthroplasty (THA) is one of the most well-known orthopedic surgeries in the world which involves the substitution of the natural hip joint by prostheses. In this process, the surface roughness of the femoral head plays a pivotal role in the performance of hip joint implants. In this regard, the nano-finishing of the femoral head of the hip joint implants to achieve a uniform surface roughness with the lowest standard deviation is a major challenge in the conventional and advanced finishing processes. In the present study, the inverse replica fixture technique was used for automatic finishing in the abrasive flow finishing (AFF) process. For this aim, an experimental setup of the AFF process was designed and fabricated. After the tests, experimental data were modeled and optimized to achieve the minimum surface roughness in the ASTM F138 (SS 316L) femoral head of the hip joint through the use of response surface methodology (RSM). The results confirmed uniform surface roughness up to the range of 0.0203 µm with a minimum standard deviation of 0.00224 for the femoral head. Moreover, the spherical shape deviation of the femoral head was achieved in the range of 7 µm. The RSM results showed a 99.71% improvement in the femoral head surface roughness (0.0007) µm under the optimized condition involving the extrusion pressure of 9.10 MPa, the number of finishing cycles of 95, and SiC abrasive mesh number of 1000.

scholarly journals Influence of Relative Displacement on Surface Roughness in Longitudinal Turning of X37CrMoV5-1 Steel

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1317
Author(s):  
Michal Skrzyniarz ◽  
Lukasz Nowakowski ◽  
Edward Miko ◽  
Krzysztof Borkowski
Keyword(s):  
Surface Roughness ◽  
Standard Deviation ◽  
Surface Texture ◽  
Roughness Parameter ◽  
Relative Displacement ◽  
Edge Radius ◽  
Shaping Process ◽  
Feed Value ◽  
Longitudinal Turning ◽  
Final Effect

The shaping process of surface texture is complicated and depends on many factors and phenomena accompanying them. This article presents the author’s test stand for the measurement of relative displacements in a tool–workpiece system during longitudinal turning. The aim of this study was to determine the influence of edge radius on the relative displacement between the tool and workpiece. The cutting process was carried out with inserts with different edge radii for X37CrMoV5-1 steel. As a result of the research, vibration charts of the tool–workpiece system were obtained. In the range of feed 0.03–0.18 mm/rev, the values of the standard deviation of relative displacements in the x-axis were obtained in the range of 0.36–0.78 μm for the insert with an edge radius of rn = 48.8 μm. As a result of the work, it was determined that for the feed value of 0.12 mm/rev for all inserts, the relative displacements are the smallest. As the final effect, the formula for forecasting the Ra roughness parameter was presented.

The Estimation of the Efficiency of Sampling, with Special Reference to Sampling for Yield in Cereal Experiments

1935 ◽  
Vol 25 (4) ◽  
pp. 545-577 ◽  
Author(s):  
F. Yates ◽  
I. Zacopanay
Keyword(s):  
Standard Deviation ◽  
Special Reference ◽  
Analysis Of Variance ◽  
Sampling Methods ◽  
Cereal Crops ◽  
Loss Of Information ◽  
Preliminary Discussion ◽  
Experimental Errors ◽  
Series Of Experiments ◽  
The Mean

The estimation of the experimental yields of cereal crops by sampling methods is considered in the light of results of eighteen experiments which were harvested by these methods at Rothamsted and its associated centres. The harvesting results of the Crop-Weather series of experiments are also included.A preliminary discussion of the interpretation of the analysis of variance as applied to sampling results is given, and an expression is found for the loss of information arising out of sampling. The results of the discussion are applicable to all types of sampling carried out on replicated experiments.The sampling and experimental errors of all the experiments have been calculated. The variation between sampling units in the same subplot (usually between l/100th and l/200th acre) was found to be such as would arise if each metre length of row had a standard deviation (about the plot mean) of the order of 25–30 per cent. of the mean yield.

Low Cost Vibration Measurement and Optimization during Turning Process

2018 ◽  
Vol 1148 ◽  
pp. 103-108 ◽  
Author(s):  
N.V.S. Shankar ◽  
A. Gopi Chand ◽  
K. Hanumantha Rao ◽  
K. Prem Sai
Keyword(s):  
Surface Roughness ◽  
Cutting Tool ◽  
Low Cost ◽  
Machining Process ◽  
Vibration Measurement ◽  
Depth Of Cut ◽  
Turning Process ◽  
Taguchi Analysis ◽  
Series Of Experiments

During machining any material, vibrations play a major role in deciding the life of the cutting tool as well as machine tool. The magnitude acceleration of vibrations is directly proportional to the cutting forces. In other words, if we are able to measure the acceleration experienced by the tool during machining, we can get a sense of force. There are many commercially available, pre-calibrated accelerometer sensors available off the shelf. In the current work, an attempt has been made to measure vibrations using ADXL335 accelerometer. This accelerometer is interfaced to computer using Arduino. The measured values are then used to optimize the machining process. Experiments are performed on Brass. During machining, it is better to have lower acceleration values. Thus, the first objective of the work is to minimize the vibrations. Surface roughness is another major factor which criterion “lower is the better” applies. In order to optimize the values, a series of experiments are conducted with three factors, namely, tool type (2 levels), Depth of cut (3 levels) and Feed are considered (3 levels). Mixed level optimization is performed using Taguchi analysis with L18 orthogonal array. Detailed discussion of the parameters shall be given in the article.

scholarly journals Effects of Microstructure, Mechanical and Physical Properties on Machinability of Graphite Cast Irons

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 285 ◽  
Author(s):  
Jiangzhuo Ren ◽  
Fengzhang Ren ◽  
Fengjun Li ◽  
Linkai Cui ◽  
Yi Xiong ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Surface Roughness ◽  
Standard Deviation ◽  
Cutting Force ◽  
Volume Fraction ◽  
Internal Surface ◽  
Drilling Process ◽  
Turning Process ◽  
Cast Irons ◽  
Mechanical And Physical Properties

Flake (FGI) and spheroidal (SGI) graphite cast irons are often used to produce workpieces, which often need to be machined. Machinability differences under various machining methods are the basis for choosing machining equipment and technology. In this work, FGI and SGI were used to produce tractor front brackets, and the machinability of both materials under turning and drilling processes was compared. The machinability (turning and drilling ability) has been evaluated in terms of machining load, chips shape, surface roughness, and tool temperature. The influence of materials microstructure and thermal conductivity on the machinability was analyzed. In the turning process, the cutting force and its standard deviation of the FGI were larger than the SGI due to the higher volume fraction of pearlite. The surface roughness was similar in both materials. In the drilling process, the even action of the friction and cutting force on the bit turned into similar drilling loads for both materials. Higher friction and lower thermal conductivity caused a higher bit temperature in SGI drilling compared to FGI. The chip breaking was worse in SGI drilling, where the longer chips scratched the internal surface of the holes, resulting in the higher surface roughness.

Investigation of the Effects of Technological Parameters on Surface Roughness in Extrusion Bars of Aluminum Alloy

2019 ◽  
Vol 889 ◽  
pp. 155-160
Author(s):  
Trong Mai Nguyen ◽  
Đuc Quy Tran ◽  
Van Nghe Pham ◽  
Van Canh Nguyen
Keyword(s):  
Surface Roughness ◽  
Aluminum Alloy ◽  
Surface Quality ◽  
Research Work ◽  
Extrusion Process ◽  
Optimal Parameters ◽  
Technological Parameters

In this research work, the result of the effects of technological parameters on surface roughness in extrusion bars of aluminum alloy were pesented. The results of this study may be used for choosing optimal parameters of extrusion process so that surface quality of extruded bar was improved.

Surface Topography Changes in Polymer-Metal Sliding—II

1983 ◽  
Vol 105 (4) ◽  
pp. 526-531 ◽  
Author(s):  
V. K. Jain ◽  
S. Bahadur
Keyword(s):  
Surface Roughness ◽  
Standard Deviation ◽  
High Density Polyethylene ◽  
Surface Profile ◽  
Data Acquisition System ◽  
Radius Of Curvature ◽  
Roughness Parameters ◽  
Poly Vinyl Chloride ◽  
Polymer Metal

The variation in the surface topographical parameters for the case of sliding between high density polyethylene and poly(vinyl chloride) pin ends and a steel disk periphery was investigated. Sliding surface profile ordinate data were obtained at 2μm intervals using a data acquisition system, both along and perpendicular to the direction of sliding. A number of surface roughness parameters, viz., the r.m.s. and c.l.a. roughness, the slope, density, and radius of curvature of asperities, the standard deviation and distribution of profile ordinates, slopes, radii of curvatures and heights of asperities were calculated using a Fortran IV computer program. The analysis showed that the surface parameters undergo a marked variation during the early part of sliding, but the variation is statistically insignificant during the later part. It was found that the standard deviation of peak heights can be approximated by the r.m.s. surface roughness.

Nano-Precision Finishing Technology Based on Magnetorheological Finishing

2009 ◽  
Vol 416 ◽  
pp. 118-122 ◽  
Author(s):  
Yao Ming Li ◽  
Xing Quan Shen ◽  
Ai Ling Wang
Keyword(s):  
Surface Roughness ◽  
Advanced Technology ◽  
Technological Parameters ◽  
Magnetorheological Finishing ◽  
Shape Precision ◽  
Surface Destruction ◽  
Series Of Experiments ◽  
Precision Finishing ◽  
Better Than

Surface roughness is normally regarded as an important criterion for assessing the quality of optic elements; surface roughness of a high-quality optic element is required to be less than RMS1nm. In this paper, a series of experiments has been conducted on the sample magnetorheological finishing machine by using self-prepared magnetorheological liquid as finishing liquid, to assess the removing efficiency of magnetorheological finishing. Optimization of technological parameters enables the authors to obtain a glass-ware with an ideal surface roughness of RMS0.56nm. Magnetorheological finishing (MRF) is an advanced technology for processing optic elements that has been developed in recent years. The technology polishes optic elements by using viscoplastic soft media produced by the MRF liquid under the variation of gradient magnetic field. Better than traditional polishing method in shape precision, surface roughness and inner surface destruction, MRF is an ideal technology for obtaining super-precision optic surface.

Analysis of contact and bending stiffness for Curvic couplings considering contact angle and surface roughness

2019 ◽  
Vol 233 (6) ◽  
pp. 1257-1267 ◽  
Author(s):  
Younghun Yu ◽  
Bora Lee ◽  
Yongjoo Cho
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Standard Deviation ◽  
Bending Stiffness ◽  
Height Distribution ◽  
Average Radius ◽  
Asperity Height ◽  
Surface Parameter ◽  
Tangential Stiffness ◽  
Nominal Contact Area

This paper develops a method for calculating the contact and bending stiffness of a Curvic coupling, and investigates stiffness changes according to the coupling shape and surface roughness characteristics. The surface of the on-site Curvic coupling is chosen as reference for a most accurate simulation. The three parameters representing the surface roughness characteristics—the standard deviation of the asperity height distribution, the average radius of asperities, and the density of asperity on the nominal contact area—are calculated with a profile of the coupling surface through a random process: the contact problem between rough surfaces is tackled using the Greenwood-Williamson model, the Curvic coupling is modeled assuming that it has as many teeth as possible within the machining limits depending on the contact angle, and the tangential stiffness resulting from the contact angle is calculated by dividing into the stick and slip regions, and is taken into account in terms of total stiffness. With this, results showed that using Curvic couplings reduces stiffness than using flat disc couplings because of the contact angle, and that the standard deviation of rough surface height is the most crucial surface parameter affecting stiffness.

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