NANO-GRAPHEME OXIDE MIXED DIELECTRIC IN EDM USING BOTH BRASS AND CU ELECTRODE

Abstract

ABSTRACT “NANO-GRAPHEME OXIDE MIXED DIELECTRIC IN EDM USING BOTH BRASS AND CU ELECTRODE” The present invention provides Nano-grapheme oxide mixed dielectric in EDM using both brass inventions is related to process improvement in EDM for machining of novel Nimonic material. The constituent elements are melted together in induction furnace to form billets. The billets are hot rolled and cold rolled subsequently to form strips of 1 mm thickness. The strip of the mentioned alloy is machined through die-sinking EDM to investigate about its machining characteristics. In the invention, the inventors tried to improve machining process which can increase MRR and decrease TWR and SR for the mentioned Nimonic alloy. The inventors used graphene oxide nano particles in the dielectric at 5g/L. Using graphene oxide mixed dielectric the machining is taken place at different parametric levels and using different tools such as Copper and brass. Figure 1

Specification

Description:TECHNICAL FIELD
[0001] The present invention relates to the field of metal removing machines, and more particularly, the present invention relates to the Nano-grapheme oxide mixed dielectric in EDM using both brass and Cu electrode.
BACKGROUND ART
[0002] The following discussion of the background of the invention is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was published, known, or part of the common general knowledge in any jurisdiction as of the application's priority date. The details provided herein the background if belongs to any publication is taken only as a reference for describing the problems, in general terminologies or principles or both of science and technology in the associated prior art.
[0003] Nimonic alloys are widely used in aerospace and automobile parts. But the machining of Nimonic alloy has been a great challenge inavionics and automobile industry. Nimonic alloys are very hard to be machined by any conventional machining process. EDM is a viable option for machining Nimonic alloys as EDM is not dependent upon the hardness of the work material. Nimonic being a conductive material can be easily machined through die sinking EDM in which generally kerosene based dielectric is used. But the material removal rate in this machining process is very low. In addition, tool wear phenomenon also persists significantly in EDM process. Surface integrity of machined surface is also co-related with the tool wear.
[0004] Hence machined surface obtained from EDM of Nimonic alloy possess large surface roughness. Hence smaller Material Removal Rate (MRR), Greater Tool Wear Rate (TWR) and Surface Roughness (SR) limits the use of EDM in machining of Nimonic alloy of fixed composition.
[0005] Vibration assisted EDM: By facilitating debris removal from the work tool interface, the machining process can be enhanced. Vibration assisted technique applied to the tool is one of the process improvement technique by which debris removal becomes easier. It is evident that the introduction of vibration to the tool can lower TWR, enhance MRR and surface integrity. The application of vibration may also stabilize machining process, decrease short circuiting and increase discharge frequency.
[0006] Use of composite tool: Composite electrode tools can be employed to increase the efficiency of EDM. Composite material of pseudo-alloy system can be used as tool material for this purpose. Composite material such as a pseudo-alloy system of copper-colloidal graphite with a graphite content of 20% is proved to be a better tool material for enhancing process capability. Composite material has the capability to stabilize arc and have better discharge frequency.
[0007] The above two methods can be employed to enhance process capability in EDM.
[0008] In light of the foregoing, there is a need for Nano-grapheme oxide mixed dielectric in EDM using both brass and Cu electrode that overcomes problems prevalent in the prior art associated with the traditionally available method or system, of the above-mentioned inventions that can be used with the presented disclosed technique with or without modification.
[0009] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies, and the definition of that term in the reference does not apply.
OBJECTS OF THE INVENTION
[0010] The principal object of the present invention is to overcome the disadvantages of the prior art by providing Nano-grapheme oxide mixed dielectric in EDM using both brass and Cu electrode.
[0011] Another object of the present invention is to provide Nano-grapheme oxide mixed dielectric in EDM using both brass and Cu electrode, wherein the process of mixing nano particles in dielectric adds simplicity in the machining process.
[0012] Another object of the present invention is to provide Nano-grapheme oxide mixed dielectric in EDM using both brass and Cu electrode, wherein the process of mixing nano particles to dielectric is simple and cheaper than any other special arrangement.
[0013] Another object of the present invention is to provide Nano-grapheme oxide mixed dielectric in EDM using both brass and Cu electrode, wherein the desirable responses can be greater compared to other techniques adopted in machining of Nimonic alloy. If machining takes place at optimal parametric levels then definitely the powder mixed technique dominates over any other technique.
[0014] Another object of the present invention is to provide Nano-grapheme oxide mixed dielectric in EDM using both brass and Cu electrode, wherein the addition of different concentration of powders different purpose of machining can be fulfilled. If MRR to be maximized for the Nimonic alloy then one concentration of powder mixed dielectric is used whereas for getting better surface finish of Nimonic alloy another concentration of powder mixed dielectric should be used. Such flexibility is unavailable in other solutions.
[0015] The foregoing and other objects of the present invention will become readily apparent upon further review of the following detailed description of the embodiments as illustrated in the accompanying drawings.
SUMMARY OF THE INVENTION
[0016] The current invention is related to process improvement in EDM for machining of novel Nimonic material. The used Nimonic alloy contains the following constituents as given in table 1. The constituent elements are melted together in induction furnace to form billets. The billets are hot rolled and cold rolled subsequently to form strips of 1 mm thickness. The strip of the mentioned alloy is machined through die-sinking EDM to investigate about its machining characteristics. Mainly, MRR, TWR and SR were focused to be evaluated in the machining process. In the invention, the inventors tried to improve machining process which can increase MRR and decrease TWR and SR for the mentioned Nimonic alloy.
[0017] The inventors used graphene oxide nano particles in the dielectric at 5g/L. Using graphene oxide mixed dielectric the machining is taken place at different parametric levels and using different tools such as Copper and brass. It was found from result that the addition of graphene oxide nanoparticles in plain dielectric improves the machining of said Nimonic alloy i.e. MRR of work material increases, TWR of tool material decreases and SR of work machined surface decreases.
[0018] Already available solutions those were discussed earlier need special tools for EDM operation. By the incorporation of special tools the process becomes expensive as its manufacturing needs special manufacturing techniques. The vibration assisted setup also requires special arrangement that can generate vibration. All these arrangements add cost to the process.
[0019] But the process of mixing nano particles in dielectric adds simplicity in the machining process. The process of mixing nano particles to dielectric is simple and cheaper than any other special arrangement. There is a chance that value of desirable responses can be greater compared to other techniques adopted in machining of Nimonic alloy. If machining takes place at optimal parametric levels then definitely the powder mixed technique dominates over any other technique.
[0020] Another special attribute of the powder mixing technique is that by the addition of different concentration of powders different purpose of machining can be fulfilled. If MRR to be maximized for the Nimonic alloy then one concentration of powder mixed dielectric should be used whereas for getting better surface finish of Nimonic alloy another concentration of powder mixed dielectric should be used. This flexibility is unavailable in other solutions.
[0021] Nano particle type: Nano graphene mixed dielectric proved to be a successful dielectric in improving machining performance in terms of MRR, TWR and SR. The machining of said Nimonic alloy is beneficial while using Nano graphene mixed dielectric. This invention should be protected.
[0022] Concentration: The concentration of graphene nanoparticles in EDM plays a great role in determining MRR, TWR and SR. 5g/L of graphene oxide nano particles in plain dielectric enhances MRR by about 35%, lower TWR by about 10% and lower SR by about 30%. Hence, the novelity of concentration of 5g/L of graphene based dielectric should be considered to be protected for machining Nimonic alloy through EDM.
[0023] While the invention has been described and shown with reference to the preferred embodiment, it will be apparent that variations might be possible that would fall within the scope of the present invention.
BRIEF DESCRIPTION OF DRAWINGS
[0024] So that the manner in which the above-recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may have been referred by embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
[0025] These and other features, benefits, and advantages of the present invention will become apparent by reference to the following text figure, with like reference numbers referring to like structures across the views, wherein:
[0026] Figure 1: Outline of EDM setup.
DETAILED DESCRIPTION OF THE INVENTION
[0027] While the present invention is described herein by way of example using embodiments and illustrative drawings, those skilled in the art will recognize that the invention is not limited to the embodiments of drawing or drawings described and are not intended to represent the scale of the various components. Further, some components that may form a part of the invention may not be illustrated in certain figures, for ease of illustration, and such omissions do not limit the embodiments outlined in any way. It should be understood that the drawings and the detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the scope of the present invention as defined by the appended claim.
[0028] As used throughout this description, the word "may" is used in a permissive sense (i.e. meaning having the potential to), rather than the mandatory sense, (i.e. meaning must). Further, the words "a" or "an" mean "at least one" and the word "plurality" means "one or more" unless otherwise mentioned. Furthermore, the terminology and phraseology used herein are solely used for descriptive purposes and should not be construed as limiting in scope. Language such as "including," "comprising," "having," "containing," or "involving," and variations thereof, is intended to be broad and encompass the subject matter listed thereafter, equivalents, and additional subject matter not recited, and is not intended to exclude other additives, components, integers, or steps. Likewise, the term "comprising" is considered synonymous with the terms "including" or "containing" for applicable legal purposes. Any discussion of documents, acts, materials, devices, articles, and the like are included in the specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention.
[0029] In this disclosure, whenever a composition or an element or a group of elements is preceded with the transitional phrase "comprising", it is understood that we also contemplate the same composition, element, or group of elements with transitional phrases "consisting of", "consisting", "selected from the group of consisting of, "including", or "is" preceding the recitation of the composition, element or group of elements and vice versa.
[0030] The powder mixing process is simple and easier to use. By mixing powders at different concentrations the machining property of dielectric is changed. The altered property can be used to enhance various responses as per desirability. The current processs also doesn't need any special arrangement for machining for the said Nimonic alloy.
[0031] Nimonic alloy being very hard and tough material is less affected by the vibration assistance and composite tool development. But when mixed dielectric is used the machining property of the dielectric is altered which in turn becomes very effective in removing material from said Nimonic alloy. So, the powder mixed process has advantageous effect in machining of Nimonic alloy of given composition.
[0032] In addition, as it has been said that the adopted process is very economical, only cost is of nano graphene powder. By use of nano graphene mixed dielectric the cost of machining reduces by significant amount. From previous literature it has been depicted that 5g/L of nanographene powder concentration bears the optimal concentration for machining of Nimonic alloy. So this level of concentration can be commercialized for machining of Nimonic alloy in EDM.
[0033] The present invention is described hereinafter by various embodiments with reference to the accompanying drawing, wherein reference numerals used in the accompanying drawing correspond to the like elements throughout the description. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiment set forth herein. Rather, the embodiment is provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art. In the following detailed description, numeric values and ranges are provided for various aspects of the implementations described. These values and ranges are to be treated as examples only and are not intended to limit the scope of the claims. In addition, several materials are identified as suitable for various facets of the implementations. These materials are to be treated as exemplary and are not intended to limit the scope of the invention.
[0034] The current invention is related to process improvement in EDM for machining of novel Nimonic material. The used Nimonic alloy contains the following constituents as given in table 1. The constituent elements are melted together in induction furnace to form billets. The billets are hot rolled and cold rolled subsequently to form strips of 1 mm thickness. The strip of the mentioned alloy is machined through die-sinking EDM to investigate about its machining characteristics. Mainly, MRR, TWR and SR were focused to be evaluated in the machining process. In the invention, the inventors tried to improve machining process which can increase MRR and decrease TWR and SR for the mentioned Nimonic alloy.
[0035] The inventors used graphene oxide nano particles in the dielectric at 5g/L. Using graphene oxide mixed dielectric the machining is taken place at different parametric levels and using different tools such as Copper and brass. It was found from result that the addition of graphene oxide nanoparticles in plain dielectric improves the machining of said Nimonic alloy i.e. MRR of work material increases, TWR of tool material decreases and SR of work machined surface decreases.
[0036] In order to improve the machining performance of EDM the inventors mixed some graphene oxide nanoparticles in dielectric and carried out the machining. While comparing the result with the machining that is carried out with plain dielectric, it is observed that the machining performance in terms of MRR, TWR and SR has increased. The detailed invention has been described below.
[0037] Firstly, the Nimonic alloy is taken as work material and brass, Cu as tool material. Die sinking EDM is used for machining that uses plain kerosene based dielectric. For EDM operation, 3 process parameters are taken at 4 different levels as represented in table 2. Some experimental runs are conducted as per orthogonal array and MRR, TWR, SR are calculated.
Table 2: Process Parameters and their levels
Parameters Level 1 Level 2 Level 3 Level 4
Vg 60 70 80 90
Ton 100 200 300 400
Fp 0.5 0.75 1 1.25
[0038] In the next step, 10 litre of plain kerosene based dielectric is taken in a container. 50 gm of graphene oxide nano particle is mixed to the dielectric to form graphene based dielectric. The mixture is first stirred through a mechanical stirrer for about 1 hr. Then the mixture is stirred for next 4 hrs through a magnetic stirrer to get a homogeneous mixture. The mixture is now ready to be used as a dielectric in EDM. The characteristics of plain dielectric and graphene based dielectric is summarized in table3.
Table 3: Properties of plain dielectric and nano graphene based dielectric
Properties Unit Plain Dielectric Nano graphene based Dielectric
Density gm/cc 0.78 0.781
Dynamic Viscosity @250C cP 1.22 0.8872
pH 8.8 8.73
Toxicity No No
[0039] Then the same experimental runs are again repeated using nano graphene based dielectric for the said Nimonic alloy. MRR, TWR and SR are calculated again for each experimental run. The values of responses for each run has been illustrated in table 4 for brass electrode and in table 5 for Cu electrode.
Table 4: Response parameters for plain and nano graphene based dielectric using brass electrode
Vg (Volt.) Ton (µs) Fp (Kgf/mm2) Plain Dielectric Graphene based Dielectric
TWR MRR Ra TWR MRR Ra
60 100 0.5 1.768 3.157 10.030 1.591 4.415 7.144
70 400 1 1.759 3.526 10.101 1.611 4.103 7.287
80 200 1.25 1.347 2.845 8.528 1.088 3.336 6.884
90 300 0.75 0.766 1.491 7.640 0.619 2.129 6.418
Table 5: Response parameters for plain and nano graphene based dielectric using Cu electrode
Vg (Volt.) Ton (µs) Fp (Kgf/mm2) Plain Dielectric Graphene based Dielectric
TWR MRR Ra TWR MRR Ra
60 100 0.5 0.077 10.302 10.543 0.069 14.119 7.233
70 400 1 0.057 9.074 10.388 0.045 11.911 7.789
80 200 1.25 0.022 6.627 8.912 0.019 7.313 6.868
90 300 0.75 0.010 3.433 8.470 0.009 4.015 5.826
[0040] From the values of responses it is observed that by the use of graphene based dielectric in EDM the machining performance of Nimonic alloy has increased. The MRR has increased by about 35%, TWR has decreased by about 10% and SR has decreased by about 30%. So one can draw inference that by the use of graphene based dielectric the EDM process enhancement has taken place. The novel process of nano particle addition in machining of novel material in EDM has solved the existing issue significantly.
[0041] Various modifications to these embodiments are apparent to those skilled in the art from the description and the accompanying drawings. The principles associated with the various embodiments described herein may be applied to other embodiments. Therefore, the description is not intended to be limited to the 5 embodiments shown along with the accompanying drawings but is to be providing the broadest scope consistent with the principles and the novel and inventive features disclosed or suggested herein. Accordingly, the invention is anticipated to hold on to all other such alternatives, modifications, and variations that fall within the scope of the present invention and appended claims.
, Claims:CLAIMS
We Claim:
1) A process for machining a novel Nimonic alloy using Electrical Discharge Machining (EDM), the alloy comprising titanium (0.48%), chromium (22.18%), iron (1.6%), nickel (59.89%), aluminum (0.55%), tungsten (12.8%), and silicon (2.5%), the process comprising:
- forming billets of the Nimonic alloy by melting the constituent elements in an induction furnace, followed by hot rolling and cold rolling to produce strips of 1 mm thickness;
- machining the Nimonic alloy strips using die-sinking EDM;
- utilizing a dielectric fluid mixed with 5g/L graphene oxide nanoparticles;
- wherein the process improves machining performance by increasing material removal rate (MRR), reducing tool wear rate (TWR), and decreasing surface roughness (SR) of the machined surface.
2) The process as claimed in claim 1, wherein the addition of 5g/L graphene oxide nanoparticles to the dielectric fluid enhances MRR by 35%, reduces TWR by 10%, and improves surface finish by decreasing SR by 30%, compared to machining without the graphene oxide-enhanced dielectric.
3) The process as claimed in claim 1, wherein the Nimonic alloy strips are machined using copper or brass electrodes as the EDM tool materials, and the addition of graphene oxide nanoparticles in the dielectric fluid enhances the machining characteristics of the alloy regardless of the electrode material.
4) The process as claimed in claim 1, wherein the graphene oxide nanoparticles added to the dielectric fluid facilitate an improved machining process by providing flexibility in machining characteristics, such that different concentrations of nanoparticles are used to optimize either maximum MRR or better surface roughness, depending on machining requirements.
5) The process as claimed in claim 1, wherein the Nimonic alloy is machined at various parametric levels, with the optimal combination of EDM parameters and graphene oxide nanoparticle concentration improving machining efficiency without the need for specialized tools or vibration-assisted setups, thus reducing cost and complexity.
6) A method for optimizing EDM performance for machining Nimonic alloy strips, the method comprising:
- forming Nimonic alloy strips with a thickness of 1 mm by hot and cold rolling;
- introducing a dielectric fluid with 5g/L graphene oxide nanoparticles during EDM machining;
- evaluating and adjusting EDM parameters such as pulse on-time, pulse off-time, and discharge current to maximize MRR, minimize TWR, and enhance surface finish (SR);
- wherein the graphene oxide nanoparticle-enhanced dielectric results in superior machining performance compared to traditional EDM processes.

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