Description:FIELD OF INVENTION
[0001]Embodiments of the present invention relate to the field of non-destructive testing (NDT) and, more specifically, a development of a contact pad and a fabrication process of the contact pad for magnetic particle inspections (MPIs). The invention focuses on achieving enhanced electrical conductivity and impact resistance in the contact pads, contributing to improved performance in MPI applications.

BACKGROUND
[0002]Non-destructive testing (NDT) methods play a crucial role in ensuring the integrity and reliability of various components and structures across diverse industries. Among the various NDT techniques, magnetic particle inspections (MPIs) stand out as an effective means of identifying surface and near-surface defects in ferromagnetic materials. The MPI machines reveal the flaws through distinct particle accumulations by generating a magnetic field and applying magnetic particles to a part that is to be tested.

[0003]The MPI machines are crucial in industries including aerospace, automotive, and manufacturing, for ensuring the integrity of critical components, improving safety, and preventing potential failures that may include severe consequences. The speed, sensitivity, and reliability of the MPI machines establish the MPI machines as invaluable tools for quality control, thereby playing a pivotal role in enhancing the safety and functionality of various industrial applications.

[0004]Further, contact pads in the MPI machines are integral components that significantly influence the accuracy and reliability of flaw detection processes. The contact pads serve as the interface between the part and the magnetic field generated by the MPI machine. The design and condition of the contact pad play a crucial role in ensuring consistent and optimal magnetic particle distribution on a surface of the part. In traditional MPI processes, the contact pads serve as essential components facilitating the application of current and the detection of anomalies. The contact pads are subjected to rigorous operational conditions, including electrical stress and mechanical impact during the testing procedure. The effectiveness of MPIs relies significantly on the quality and durability of the contact pads

[0005]The material composition and wear resistance of the contact pads are vital considerations to maintain reliable and reproducible inspections over time. Regular inspection and maintenance of the contact pads are essential to prevent degradation, uneven wear, and contamination. The effectiveness of the MPIhinges on the careful selection and meticulous upkeep of the contact pads, thereby contributing to the precision and success of the non-destructive testing in the various industrial applications. However, existing contact pads involve the use of imported materials, incurring substantial costs in their fabrication. Moreover, limitations in their design and composition may compromise their overall performance, impacting factors such as electrical conductivity, resistance to hot spots, and mechanical strength.

[0006]In the existing technology, an electrode board is disclosed. The electrode board comprises a base portion to which power is supplied and an electrode portion that is held by the base portion. The electrode portion is formed of an assembly of conductive wires and at least one work contact surface. Further, a woven fabric of the conductive wires is formed by pressing with a strong pressure. However, the electrode board may increase the potential for false signals and readings due to variations in electrical conductivity, surface conditions, and other external factors. This may lead to misinterpretations and may compromise the accuracy of the flaw detection processes.

[0007]Similarly in another existing technology, a magnetic particle testing apparatus is disclosed. The apparatus comprises a first handle and a second handle. Further, the apparatus allows a user to grip between the first handle and the second handle to control a length of an integrated coil electrode unit, thereby improving the efficiency of the part. However, the effectiveness of the apparatus is influenced by an orientation of the flaw relative to the magnetic field, thereby potentially leading to variations in detectability based on an alignment of the flaw.

[0008]There are various technical problems with the contact pads in the prior art. In the existing technology, irregularities in the magnetic field generated by the MPI machine may result in uneven particle distribution and compromise the detection of the flaws. The contact pads may experience wear and tear due to repeated use. This may lead to uneven surfaces and degradation of the material, thereby affecting the consistency of contact between the contact pad and the part. The contact pads fail to prevent significant electric current drops and to demonstrate resilience against the formation of hot spots.

[0009]Therefore, there is a need for the contact pad to address the aforementioned issues by ensuring proper electrical contact with the part, thereby facilitating the flow of the electric current during the inspection. Also, there is a need for the contact pad to provide a uniform and effective magnetic particle distribution on the surface of the part, thereby enhancing sensitivity to the flaws during the inspection process.

SUMMARY

[0010]This summary is provided to introduce a selection of concepts, in a simple manner, which is further described in the detailed description of the disclosure. This summary is neither intended to identify key or essential inventive concepts of the subject matter nor to determine the scope of the disclosure.

[0011]In order to overcome the above deficiencies of the prior art, the present disclosure is to solve the technical problem by providing a contact pad and a fabrication process of the contact pad.

[0012]In accordance with an embodiment of the present invention, the contact pad is disclosed. The contact pad comprises a composite element and a housing element. The composite element is formed by immersing a non-ferrous conductive mesh into a molten non-ferrous metal (NFM) alloy. The non-ferrous conductive meshis made up of a Cu metal that comprises a copper content of 99.3%. In an alternative embodiment, the non-ferrous conductive mesh is formed from a group of materials that comprises at least one of a: copper (Cu), zinc (Zn), tin (Sn), and silver (Ag). The molten NFM alloy is formed by melting and casting of NFM elements. The NFM elements comprise 5-11.5% zinc, 0.2%-2% silver, and 85%- 93.8% tin.

[0013]In an embodiment, the housing element is configured with a housing slot to house the composite element by metal joining methods to form the contact pad. The housing element is made up of a Cu metal that comprises a copper content of 99.3%. The metal joining methods comprise one of a: brazing, welding, soldering, fusion bonding, and riveting.

[0014]In an embodiment, the fabrication process of the contact pad is provided. In the first step, the fabrication process comprises cutting the non-ferrous conductive mesh into a pre-defined size for a base of the composite element. The pre-defined size of the non-ferrous conductive mesh is selected based on dimensions of a part to be tested.

[0015]In the next step, the fabrication process comprises melting the NFM elements at a pre-defined temperature to prepare a molten alloy. The NFM elements comprise 5-11.5% zinc, 0.2%-2% silver, and 85%- 93.8% tin. In the next step, the fabrication process comprises casting the molten alloy upon stirring the molten alloy for a time ranging between 3 minutes and 5 minutes to form an NFM ingot. The pre-defined temperature for melting the NFM elements and the NFM ingot ranges between 450°C and 500°C.The composite element and the housing element are assembled by the metal joining methods. The metal joining methods comprise one of the: brazing, welding, soldering, fusion bonding, and riveting.

[0016]In the next step, the fabrication process comprises melting the NFM ingot at the pre-defined temperature for producing the molten NFM alloy. The composite element is characterized by a weight percentage ratio of the non-ferrous conductive mesh to the molten NFM alloy is 1:1. In the next step, the fabrication process comprises forming the composite element by immersing the non-ferrous conductive mesh into the molten NFM alloy. In the next step, the fabrication process comprises fabricating the housing element configured with the housing slot based on a shape of the composite element. In the next step, the fabrication process comprises assembling the composite element and the housing element by positioning the composite element within the housing slot for the fabrication of the contact pad.

[0017]To further clarify the advantages and features of the present invention, a more particular description of the invention will follow by reference to specific embodiments thereof, which are illustrated in the appended figures. It is to be appreciated that these figures depict only typical embodiments of the invention and are therefore not to be considered limiting in scope. The invention will be described and explained with additional specificity and detail with the appended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]The disclosure will be described and explained with additional specificity and detail with the accompanying figures in which:

[0019]FIG. 1illustrates an exemplary exploded view and assembled view of a contact pad, in accordance with an embodiment of the present disclosure;

[0020]FIG. 2 illustrates an exemplary flow chart depicting a fabrication process of the contact pad, in accordance with an embodiment of the present disclosure; and

[0021]FIG. 3 illustrates an exemplary experimental set-up for testing of a crankshaft on a magnetic particle inspection(MPI) machine, in accordance with an embodiment of the present disclosure.

[0022]Further, those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the method steps, chemical compounds, equipment and parameters used herein may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the figures with details that will be readily apparent to those skilled in the art having the benefit of the description herein.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0023]For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiment illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as would normally occur to those skilled in the art are to be construed as being within the scope of the present disclosure.

[0024]The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or method. Similarly, one or more components, compounds, and ingredients preceded by "comprises... a" does not, without more constraints, preclude the existence of other components or compounds or ingredients or additional components. Appearances of the phrase "in an embodiment", "in another embodiment" and similar language throughout this specification may, but not necessarily do, all refer to the same embodiment.

[0025]Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. The system, methods, and examples provided herein are only illustrative and not intended to be limiting.

[0026]In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings. The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.

[0027]Embodiments of the present invention relate toa development of a contact pad and a fabrication process of the contact pad for magnetic particle inspections (MPIs).

[0028]FIG. 1refers to an exemplary exploded view and assembled view of the contact pad 100,in accordance with an embodiment of the present disclosure.

[0029]According to an exemplary embodiment of the disclosure, the contact pad 100 is disclosed. The contact pad 100 comprises a composite element 102 and a housing element 104. The composite element 102 is formed by immersing a non-ferrous conductive mesh into a molten non-ferrous metal (NFM) alloy. The non-ferrous conductive mesh is formed from a group of materials that comprises, but not limited to, at least one of a: copper (Cu), zinc (Zn), tin (Sn), silver (Ag), and the like. The molten NFM alloy is formed by melting and casting of NFM elements. The NFM elements comprise 5-11.5% zinc, 0.2%-2% silver, and 85%- 93.8% tin.

[0030]In an exemplary embodiment, the housing element104 is configured with a housing slot 106 to house the composite element 102 by metal joining methods to form the contact pad 100. The housing element 104 is made up of a Cu metal that comprises a copper content of 99.3%. The metal joining methods comprise, but not limited to, one of a: brazing, welding, soldering, fusion bonding, riveting, and the like. This deliberate selection of metal joining methods ensures a robust and durable connection between the housing element 104 and the composite element 102, contributing to the overall effectiveness and longevity of the contact pad 100.

[0031]FIG. 2 refers to an exemplary flow chart depicting the fabrication process 200 of the contact pad 100, in accordance with an embodiment of the present disclosure.

[0032]According to an exemplary embodiment of the disclosure, the contact pad 100 and the fabrication process 200 (hereinafter the fabrication process 200 is referred to as the process 200) of the contact pad 100is disclosed. At step 202,the process200 includes cutting a non-ferrous conductive mesh, into a pre-defined size tailored to dimensions of a part intended for testing. Thenon-ferrous conductive mesh serves as a base of a composite element. The selection of non-ferrous materials is crucial to prevent interference with magnetic fields. The precision in sizing is paramount, ensuring that the contact padaligns precisely with the dimensions of the part to be tested. The non-ferrous conductive mesh is made up of a Cu metal that comprises a copper content of 99.3%. In an alternative exemplary embodiment, the non-ferrous conductive meshis formed from a group of materials that may include, but not limited to, at least one of the: copper (Cu), zinc (Zn), tin (Sn), silver (Ag), and the like.

[0033]At step 204, the process 200 includes the non-ferrous metal(NFM) elements that are subjected to a carefully controlled melting procedure at a pre-defined temperature, resulting in the formation of a molten alloy. The NFM elements comprise 5-11.5% zinc, 0.2%-2% silver, and 85%- 93.8% tin. In an alternative embodiment, the percentages and composition of the NFM elements may vary according to the requirement.

[0034]At step 206, the process 200 includes casting the molten alloy, achieved through stirring the molten alloy for a time ranging between 3 minutes and 5 minutes, ultimately yielding an NFM ingot. This crucial step ensures homogeneity and proper amalgamation of the molten alloy constituents. The pre-defined temperature for melting both the NFM elements and the NFM ingot falls between 450°C to 500°C, underscoring the precision required in the process 200.

[0035]At step 208, the process 200 includes melting the NFM ingot at the pre-defined temperature to generate a molten NFM alloy. This critical step ensures the transformation of the NFM ingot into a malleable and homogeneous state, ready for further processing. Notably, the composite element is distinguished by a specific weight percentage ratio, with the non-ferrous conductive mesh carefully combined with the molten NFM alloy at a 1:1 ratio. The ratio represents a carefully calibrated combination aimed at achieving optimal electrical conductivity and other desired material properties in the contact pad. The molten NFM alloy exhibits lower electrical resistivity compared to pure NFM, thereby ensuring a seamless operation without any instances of an electrical current drop and hot spots.

[0036]At step 210, the process200 includes the formation of the composite element by immersing the non-ferrous conductive mesh into the molten NFM alloy. This step is crucial for ensuring the intimate integration of the non-ferrous conductive mesh within the molten NFM alloy, allowing for a seamless and uniform distribution of the non-ferrous conductive mesh throughout the molten NFM alloy. The immersion process facilitates the adherence of the molten NFM alloy to the non-ferrous conductive mesh, thereby creating the cohesive and durable composite element.

[0037]In an exemplary embodiment, the composite element is designed to ensure a cushioning effect while maintaining a conformal contact with the part being tested. The molten NFM alloy strikes a balance between being firm enough to resist wear, soft enough to ensure the conformal contact, and providing high electrical conductivity. The conformal contact of the composite element ensures that the testing process of the part is not only protective against impact and the hot spots but also allows for precise and consistent electrical conductivity, thereby meeting the fundamental requirements for the magnetic particle inspection (MPI).

[0038]At step 212, process200 includes fabricating a housing element configured with a housing slot that corresponds to a shape of the composite element. The housing element is constructed from a pure Cu metal, consisting of the copper content of 99.3%.The precision in crafting the housing element to match the shape of the composite element ensures a snug fit and optimal integration. The high copper content contributes to the robustness and conductivity of the housing element, thereby making it well-suited for applications where durability and efficient electrical performance are paramount. Furthermore, depending on the requirement the composition and proportion of material may vary for constructing the housing element.

[0039]At step 214, the process200 includes assembling the composite element and the housing element to create the contact pad employed in MPI machines. This assembly involves positioning the composite element within the housing slot, thereby aligning the composite element within the housing slot accurately to meet the specifications required for optimal performance. The joining of the composite element and the housing element is accomplished through various metal joining methods. The metal joining methods may include, but not limited to, at least one of the: brazing, welding, soldering, fusion bonding, riveting, and the like. The metal joining methods ensure a robust and durable connection between the composite element and the housing element, crucial for the functionality of the contact pad.

[0040]FIG. 3 illustrates an exemplary experimental set-up 300 for testing of a crankshaft302 on the MPI machine, in accordance with an embodiment of the present disclosure.

[0041]In the experimental set-up 300, the crankshaft 302 serves as the part under examination. The contact pads100functions as a vital interface between the crankshaft 302and the MPI machine, thereby making contact on both sides of the crankshaft302. The molten NFM alloy, meticulously designed, meets service requirements, particularly excelling in high hardness to resist deformation caused by the impacts at the crankshaft 302ends. After securely holding the crankshaft302, the electrical current is applied through the crankshaft 302via the contact pads100. Subsequently, the crankshaft 302is scanned under an Ultraviolet (UV) light to meticulously detect any cracks and abnormalities in the crankshaft302, thereby providing a comprehensive assessment of the structural integrity of the crankshaft302.

[0042]Numerous advantages of the present disclosure may be apparent from the discussion above. In accordance with the present disclosure, the contact pad and the fabrication process of the contact pad are provided. The contact pads do not degrade, thereby showcasing robust durability. The contact pads are cost-effective and boast an extended service life. The housing element is reusable, further contributing to its economic efficiency. The contact pad is highly conductive and withstands mechanical strength to bear the part impact at the time of testing. Furthermore, the contact pad prevents any significant electrical current drop and resists the occurrence of the hot spots.

[0043]While specific language has been used to describe the invention, any limitations arising on account of the same are not intended. As would be apparent to a person skilled in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

[0044]The figures and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, the order of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts need to be necessarily performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.
, Claims:I/ We Claim:
1. A contact pad (100), comprising:
a composite element (102) formed by immersing a non-ferrous conductive mesh into a molten non-ferrous metal (NFM) alloy; and
a housing element (104) configured with a housing slot (106) to house the composite element (102) by metal joining methods to form the contact pad (100).
2. The contact pad (100) as claimed in claim 1, wherein the non-ferrous conductive mesh and the housing element (104) are made up of a copper (Cu) metal, comprises a copper content of 99.3%.
3. The contact pad (100) as claimed in claim 1, wherein the molten non-ferrous metal (NFM) alloy is formed by melting and casting of non-ferrous metal (NFM) elements,
the non-ferrous metal (NFM) elements comprise 5-11.5% zinc, 0.2%-2% silver, and 85%- 93.8% tin.
4. The contact pad (100) as claimed in claim 1, wherein the metal joining methods comprise one of a: brazing, welding, soldering, fusion bonding, and riveting.
5. A fabrication process (200) of a contact pad (100), comprising:
cutting a non-ferrous conductive mesh into a pre-defined size for a base of a composite element (102);
melting non-ferrous metal (NFM) elements at a pre-defined temperature to prepare a molten alloy;
casting the molten alloy upon stirring the molten alloy for a time ranging between 3 minutes and 5 minutes to form a non-ferrous metal (NFM) ingot;
melting the non-ferrous metal (NFM) ingot at the pre-defined temperature for producing a molten non-ferrous metal (NFM) alloy;
forming the composite element (102) by immersing the non-ferrous conductive mesh into the molten non-ferrous metal (NFM) alloy;
fabricating a housing element (104) configured with a housing slot (106) based on a shape of the composite element (102); and
assembling the composite element (102) and the housing element (104) by positioning the composite element (102) within the housing slot (106) for the fabrication of the contact pad (100).
6. The fabrication process (200) as claimed in claim 5, wherein the pre-defined size of the non-ferrous conductive mesh is selected based on dimensions of a part to be tested.
7. The fabrication process (200) as claimed in claim 5, wherein the non-ferrous metal (NFM) elements comprise 5-11.5% zinc, 0.2%-2% silver, and 85%- 93.8% tin.
8. The fabrication process (200) as claimed in claim 5, wherein the pre-defined temperature for melting the non-ferrous metal (NFM) elements and the non-ferrous metal (NFM) ingot ranges between 450°C and 500°C.
9. The fabrication process (200) as claimed in claim 5, wherein the composite element (102) is characterized by a weight percentage ratio of the non-ferrous conductive mesh to the molten non-ferrous metal (NFM) alloy is 1:1.
10. The fabrication process (200) as claimed in claim 5, wherein the composite element (102) and the housing element (104) are assembled by metal joining methods,
the metal joining methods comprise one of a: brazing, welding, soldering, fusion bonding, and riveting.

Dated this 14th day of February,2024

Vidya Bhaskar Singh Nandiyal
Patent Agent (IN/PA-2912)
IPExcel Services Private Limited
AGENT FOR APPLICANTS