Fabrication Study of Cu-C-Ni for EDM Electrode by a Sintering Technique

2020 ◽  
Vol 841 ◽  
pp. 259-265
Author(s):  
Pichai Janmanee ◽  
Apiwat Muttamara ◽  
Rattikorn Saodaen ◽  
Aphichart Rodchanarowan
Keyword(s):  
Optimum Combination ◽  
Electric Resistivity ◽  
Work Piece ◽  
Metal Powders ◽  
Soaking Time ◽  
Before And After ◽  
Common Grade ◽  
Copper Distribution ◽  
Porosity Percentage ◽  
Gas Ratio

The aim of this research was to study the feasibility for applications related to powder metallurgy in EDM electrode fabrication by combination of the percentage Cu-C-Ni element. The experiment was performed by comparing preliminary distribution results of particle size before and after the grinding of metal powders. The work-piece was pressed at a pressure of 200 Psi using a uniaxial press machine. The pressed green compact work-piece was then baked in a furnace. The gas inside the furnace that was used to control the temperature during the cold press procedure had a mixture gas ratio between argon and hydrogen of 95:5 (common grade) at 1030 oC and a soaking time of one hour. The results were examined by comparing the electric resistivity property, apparent density, bulk density as well as the porosity percentage inside the work piece material. The results revealed that the optimum combination of percentage Cu-C-Ni element was Cu92-C3-Ni5 (%wt), leading to the satisfactory Copper distribution in most of the structure. The size of sub sieve powder after grinding was found to be 22-31 micron with an electric resistivity of 1.45829E-05 k-ohm*cm. The minimum porosity percentage was found to be 2.19 %. Therefore, the element properties were found to be suitable for using as an electrode in EDM work when compared to that of the electrode prototype (EDM C3).

Optimization of Chitosan/PVA Concentration in Fabricating Nanofibers Membrane and its Prospect as Air Filtration

2017 ◽  
Vol 901 ◽  
pp. 20-25 ◽  
Author(s):  
Himayatus Shalihah ◽  
Ahmad Kusumaatmaja ◽  
Ari Dwi Nugraheni ◽  
Kuwat Triyana
Keyword(s):  
Electrospun Fiber ◽  
Chemical Compounds ◽  
Average Diameter ◽  
Air Filtration ◽  
Maximum Condition ◽  
Chemical Absorption ◽  
Fiber Mats ◽  
Before And After ◽  
Porosity Percentage ◽  
Scanning Electron

Chitosan/polyvinyl-alcohol (Chitosan/PVA) based nanofibers were successfully produced using electrospinning machine and investigated their application as air filtration. Firstly, 2 wt% chitosan was dissolved to 1 wt% acetic acid followed by mixing with PVA solution to produce fiber mats or membrane. Secondly, the morphology and diameter of the electrospun fiber were analyzed by using a scanning electron microscopy (SEM), while the chemical compounds in the membrane were characterized using Fourier transform infrared spectroscopy (FTIR). It was found that the conductivity of solution increased by the concentration of chitosan. Meanwhile, the average diameter and percentage of porosity decreased due to the upsurge of the conductivity of the solution. The average diameter of PVA 13 wt% was and the percentage of porosity were 50.32%. The maximum condition of chitosan/PVA was obtained at 20/80 wt%, in line with the average of fiber diameters and the percentage of porosity were 25.32%. Physicochemical properties of chitosan/PVA solution, such as conductivity, morphology, and chemical absorption were investigated before and after the air filtration. The porosity percentage of PVA 13wt% after air filtration changed to 35.85% and the percentage of porosity of chitosan/PVA 20/80 became 25.32%. Remarkable absorption peaks of PVA 13wt% exhibited and - shifted after the air filtration test, it was indicating that functional groups had been reduced. The chemical absorption of chitosan/PVA 20/80 wt% showed at the the region then disappeared after the air filtration test.

scholarly journals TO STUDY MECHANICAL PROPERTIES OF SPRING LIKE SPECIMEN BEFORE AND AFTER DIFFERENT HEAT TREATMENT OPERATIONS

2020 ◽  
Vol 6 (6) ◽  
pp. 1-8
Author(s):  
Amit Kumar
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Treatment Temperature ◽  
Muffle Furnace ◽  
Soaking Time ◽  
Standard Data ◽  
Treatment Processes ◽  
Specimen Material ◽  
Material Specimen ◽  
Before And After

In this work we have analyzed the effect heat treatment on properties of spring shape steel specimens under various heat treatment processes. Specimen was subjected to heat treatment in electric muffle furnace. Heat treatment temperature, soaking time and cooling rate were selected as per phase diagram of specimen material. Specimen was tested for mechanical properties before and after heat treatment. Two processes annealing and normalizing compared with respect to their effect on properties of spring shape specimens in reference with standard data for steel used.

Extraction of Oil Heteroatomic Compounds Using Metal Powders

2016 ◽  
Vol 685 ◽  
pp. 743-747 ◽  
Author(s):  
E.B. Golushkova ◽  
Alexander P. Ilyin ◽  
A.V. Mostovshchikov
Keyword(s):  
Thermal Decomposition ◽  
Electron Microscope ◽  
Ir Spectroscopy ◽  
Scanning Electron Microscope ◽  
Metal Powders ◽  
Elemental Analyses ◽  
Before And After ◽  
Heteroatomic Compounds ◽  
Scanning Electron

The paper presents results of scanning electron microscope (SEM) investigations, differential thermal and elemental analyses, and infrared (IR) spectroscopy of micron powders obtained by thermal decomposition of cupric and nickel oxalates before and after their blending with oil. The oil treatment modifies the powder compositions, heteroorganic compounds extracted from oil are observed on their surface. The analysis shows that materials based on copper and nickel micron powders can be used for the prepurification of crude hydrocarbons from heteroatomic compounds.

scholarly journals Hybrid Reinforced Composite Material from Garbage to Biomaterials

2019 ◽  
Vol 8 (9) ◽  
pp. 3346-3349 ◽  
Keyword(s):  
Composite Material ◽  
Impact Strength ◽  
Water Retention ◽  
Fine Powder ◽  
Soaking Time ◽  
Reinforced Composite ◽  
Before And After ◽  
Egg Shell ◽  
Moisture Conditions ◽  
Reinforced Composite Material

A hybrid reinforced composite material which fundamentally contains horticulture squander materials like banana stem outer layer (Musa sepientum) modified to powder form, egg shell modified to fine powder ,the said powders (powder have a size in a range of 10 to 50 microns) being mixed in a matrix of bio epoxy resin using a catalyst to effect complete mixing of the said powdered fibers to yield the said hybrid reinforced composite, the said hybrid composite capable of being molded to any geometrical object, the said composite having a low water retention property with retention being in a range of 14-23% with a soaking time of 120 hrs. Before and after chemical treatment in both with and without moisture, the youngs modulus varies from 12321.5241 N/mm2 to 25779.2532 N/mm2 , the flexural values varies from 17.4 N/mm2 to 25.5 N/mm2 ,impact strength varies from 12.6 J to 20.9 J , % of elongation varies from 5.6% to 10.1%. The composite has negligible change in tensile properties up to a load of 270 Kg also flexural properties and impact strength of the composite were not be affected by under moisture conditions.

Experimental Study on Frictional Force and Wear Life of Oilless Sintered-Metal Bearings for the Reliability of the Geared Motor

2006 ◽  
Vol 326-328 ◽  
pp. 585-588
Author(s):  
Se Doo Oh ◽  
Yun Ha Shin ◽  
Young Ze Lee
Keyword(s):  
Electron Microscopy ◽  
Journal Bearing ◽  
The Other ◽  
Metal Powders ◽  
Sintered Metal ◽  
Wear Life ◽  
Before And After ◽  
Oil Flow ◽  
Frictional Forces ◽  
Scanning Electron

Oilless bearings, which are made with metal powders and then impregnated by oils, are widely used in rotating components. The friction coefficients and the oil loss rates of two types of oil-impregnated sintered-metal bearings (porous bearings, oilless bearings, or oilless metals) with varying loads were measured. One is the Cu-based bearing and the other is Fe-based bearing. The frictional forces of the bearings were measured using the journal bearing tester. By measuring the change of weight before and after sliding tests, the oil losses of oilless bearings were surveyed. Also, PV curves, which could be used to predict the life of the oilless bearing, were plotted. By observing the roundness, the cylindericity and the images of scanning electron microscopy of bearings before and after sliding tests, the tribological characteristics of the bearings were evaluated. It was found that Fe-based bearing show lower friction, more oil flow, less wear and longer life than Cu-based bearing.

Influence of Pasteurization Before and After Separation of Cream on the Oxidative Stability of Ripened Cream Butter

1977 ◽  
Vol 40 (7) ◽  
pp. 480-483
Author(s):  
J. FOLEY ◽  
J. J. KING
Keyword(s):  
Oxidative Stability ◽  
Pasteurized Milk ◽  
Relative Ratio ◽  
Before And After ◽  
Copper Distribution ◽  
Fat Globule

Ripened cream butter manufactured from cream separated from pasteurized milk (80 C for 15 sec) was more susceptible to oxidative changes than the corresponding butter manufactured from cream which was separated from milk at 50 C and the cream subsequently pasteurised (80 C for 15 sec). The propensity to oxidation is related to changes in copper distribution between the serum and fat globule phases and also to the relative ratio of serum to fat at the time of pasteurization.

scholarly journals A Framework for Surface Modification by Electrical Discharge Coating using Variable Density Electrodes

2021 ◽  
Vol 309 ◽  
pp. 01093
Author(s):  
Mohd Yunus Khan ◽  
P. S. Rao ◽  
B.S. Pabla
Keyword(s):  
Surface Modification ◽  
Electrical Discharge ◽  
Variable Density ◽  
Work Piece ◽  
Hard Material ◽  
Metal Powders ◽  
Material Transfer ◽  
Modification Technique ◽  
Polarity Condition ◽  
Surface Modification Techniques

Surface modification is the process of altering physical or chemical characteristics of the work-piece surface. In this paper, various surface modification techniques have been discussed. One of the most appropriate surface modification technique is electrical discharge coating (EDC), in which the hard material is made to deposit onto the work-piece in a state of reverse polarity condition. Different mechanisms of carrying out EDC are presented. Deliberate material transfer takes place by using electrodes or by dispersant of metal powders into the di-electric. A detailed review of the literature on the theme of surface modification through the EDC has been conducted. In last, a framework for conducting surface modification by EDC employing using density electrodes of same material is presented.

Application Research of NC Machining of Circular-Arc Aligned Gear

2011 ◽  
Vol 317-319 ◽  
pp. 264-268
Author(s):  
Ying Liang Yu ◽  
Feng Qin Ding ◽  
Zhi Yi Miao ◽  
De Qing Yang
Keyword(s):  
Horizontal Displacement ◽  
Vertical Displacement ◽  
Nc Machining ◽  
Numerical Control ◽  
Good Effect ◽  
Work Piece ◽  
Application Research ◽  
Circular Arc ◽  
Before And After ◽  
Uniform Change

Abstract: numerical control system is used to control the gear hob and gear blank in autorotation and linkage generative movement, to realize the machining of teeth shape and teeth dividing; and at the same time it controls the vertical displacement of the gear hob and the horizontal displacement of gear blank, to make a circular arc track whose radius is the sum of gear blank’s radius and gear hob’s radius, thus realizing the NC machining of circular-arc aligned gear. Before and after the machining of teeth form, transition arc is used to finish the trimming and thinning of the teeth thickness at the teeth end; on the prerequisite of machining the circular-arc aligned gear, this method successfully solves the puzzle of gear chamfering, and discharges all gear burr into the lower end of the teeth. The advantage of this machining method lies in that when the hob cuts deeper, as the both side-blades are cutting the work-piece at the same time, the thinning on both sides are quite symmetrical, and the fine symmetry remains during the uniform change of the teeth thickness. So, the machining precision of the parts is prior to the requirements in the drawing, and this method yields good effect, which broadens the application of NC technology.

The Research on Process of Deep Cryogenic Treatment for W4Mo3Cr4VSi HSS Drill

2010 ◽  
Vol 97-101 ◽  
pp. 457-460 ◽  
Author(s):  
Hong Juan Yan ◽  
Hong Hai Xu ◽  
Ying Liu
Keyword(s):  
Orthogonal Experiment ◽  
Cryogenic Treatment ◽  
Deep Cryogenic Treatment ◽  
Soaking Time ◽  
Experiment Method ◽  
Before And After ◽  
Orthogonal Experiment Method ◽  
Enhance Wear Resistance ◽  
Carbide Particles ◽  
Soaking Temperature

The Deep Cryogenic Treatment(DCT) process of W4Mo3Cr4VSi HSS was studied by orthogonal experiment method. The paper analysed the effect of various DCT process parameters on mechanical properties and observed microstructure before and after DCT treatment by the SEM. The results show that the effect of soaking temperature on the properties of drill is the first factor, the soaking time is second and the cooling rate is third. DCT enhances the transformation of austenite to martensite, and distributable carbide particles are precipitated from martensite. Therefore DCT increase hardness and enhance wear resistance of twist drill.

Preparation and Characterization Cu-Cr Contact Material and Study their Hardness and Conductivity

2012 ◽  
Vol 585 ◽  
pp. 250-254
Author(s):  
Kuntal Maiti ◽  
M. Zinzuwadia ◽  
J. Nemade
Keyword(s):  
Powder Processing ◽  
Circuit Breaker ◽  
Grain Morphology ◽  
Sintered Sample ◽  
Processing Route ◽  
Vacuum Furnace ◽  
Contact Material ◽  
Soaking Time ◽  
Vacuum Circuit Breaker ◽  
Before And After

Cu-Cr contact material is used in medium voltage, high current vacuum interrupters. Vacuum interrupter is the heart of Vacuum Circuit breaker. Contact tips are usually made using powder metallurgical techniques in disk shape. These disks are machined to required dimensions and then hermitically sealed by vacuum brazing. The properties of the final contact tips are thus usually rarely studied. In the present study the properties before and after the vacuum sealing are compared in order to establish a correlation between them. The Cu-Cr contact tips were made under different compaction pressures, sintering temperatures and soaking time periods. Cu-Cr contacts were prepared by powder processing route and sintering in vacuum furnace at the temperatures of 1050°C for different soaking time period of 4, 6 and 8 Hrs. The samples were then subjected to simulated sealing cycle at temperatures (870 and 960°C). The electrical conductivity, hardness, microstructure and grain morphology of all the samples were studied. Properties of as-sintered and after sealing were analyzed and compared. The results of quantitative microscopy shows the better result on sintered sample soaked for 4 Hrs. The hardness and conductivity of the sample without brazing, varies between 79.9 - 83.8 HRF and 37.9 - 43.1% IACS respectively. The hardness and conductivity of the brazed sample varies between 52.5 - 63.42 HRF and 48.32 - 51.33 %IACS respectively.

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