DESC:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003

COMPLETE SPECIFICATION
[See section 10, Rule 13]

A PROCESS OF STRENGTHENING FERROUS MATERIALS;

MAHINDRA & MAHINDRA LIMITED, HAVING ADDRESS: MAHINDRA & MAHINDRA LIMITED, MAHINDRA RESEARCH VALLEY (MRV) MAHINDRA WORLD CITY, ANJUR (PO), CHENGALPATTU – 603204, KANCHEEPURAM DIST., STATE-TAMIL NADU, COUNTRY-INDIA

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

Field of the invention:
The present invention relates to strengthening processes and more particularly, to a process of strengthening ferrous material and an arrangement thereof.
Background of the invention
Strengthening is a process of increasing mechanical strength of a material as compared to its previous strength. The strengthening may be done by subjecting the material to chemical or mechanical process. The material undergoes structural deformation during strengthening processes.
The current chemical processes used for strengthening material result in formation of by-products. Such processes involve many steps that make them time taking and costly. The mechanical processes include heating and cooling of materials at desired temperature range. The prior art include various such processes, for example patent number US2454432A discloses a process for strengthening a low carbon high strength steel. In this process the low carbon high strength steel undergoes tempering, cold-working and ageing.
The process cited in the prior art and many such similar processes fail to give uniform structural formation of the resultant strengthened material. If the temperature range and heating and cooling rate is not controlled properly it may lead to formation of uneven structure of the material. Such processes may also introduce air voids in the material. Air voids and uneven structural deformation makes the material brittle at some portions thereof.
Accordingly, there is a need of a faster process for strengthening ferrous materials that overcomes disadvantages cited in the prior art and gives refined uniform structure to the ferrous material.
Summary of the invention
In an embodiment, the present invention provides an arrangement for strengthening of a ferrous material that comprises a ferrous material, a stationary holder, a rotating holder, a heat insulating jacket and an induction coil. The ferrous material is preferably positioned between the stationary holder and the rotating holder. The ferrous material is enclosed by the insulating jacket. The induction coil is positioned between the stationary holder and the rotating holder. The rotating holder has a predefined rotational movement and a predefined axial movement along the central axis of the ferrous material.
In one embodiment, the present invention provides a process for strengthening of a ferrous material that comprises an initial step of positioning the ferrous material between the stationary holder and the rotating holder. In next step, the ferrous material is heated using the induction coil to a red hot temperature. In next step, a predefined rotational movement and a predefined axial movement is facilitated to the rotating holder thereby causing strengthening of the heated ferrous material. In final step, controlled cooling of the ferrous material is facilitated thereby introducing a cooling media inside an insulating jacket which encloses the ferrous material. This allows the ferrous material to have an internal structure of a predefined size.
Brief description of the drawings
FIG. 1 is a top view of an arrangement of strengthening a ferrous material, in accordance with an embodiment of the present invention; and
FIG. 2 is a graphical representation of strain amplitude Vs Transient stress ratio for the strengthened ferrous material treated by a process of strengthening the ferrous material in accordance with an embodiment of the present invention.
Detailed description of the invention
In general aspect the present invention discloses a process of strengthening ferrous materials by application of stress, pressure, heat and a cooling media. The process of the present invention is used for strengthening all forms of ferrous materials for forming an exceptionally refined internal structure that is evenly distributed throughout the cross section of the ferrous materials.
The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures.
Referring to FIG. 1, an arrangement 100 for strengthening of a ferrous material in accordance with an embodiment of the present invention is shown. The arrangement 100 includes a ferrous material 10, a stationary holder 20, a rotating holder 30, a heat insulating jacket 40 and an induction coil 50.
The ferrous material 10 is positioned between the stationary holder 20 and the rotating holder 30. The rotating holder 30 is configured to have a predefined rotational movement and a predefined axial movement with respect to a central axis of the ferrous material 10. In this embodiment, the rotating holder 30 is configured to rotate in a clockwise direction and/ or an anticlockwise direction along the central axis of the ferrous material 10. The rotating holder 30 is configured to move in a forward and/ or a backward direction along the central axis of the ferrous material 10. The ferrous material 10 to be strengthened is enclosed by the insulating jacket 40. The induction coil 50 is preferably positioned between the stationary holder 20 and the rotating holder 30. However, it is understood that the position of induction coil may vary in other alternative embodiments of the present invention. The stationary holder 20 and the rotating holder 30 are made up of materials such as metallic materials, non-metallic materials, ceramic materials and the like.
In one embodiment, a process of strengthening ferrous materials in accordance with the present invention is described hereinafter-
In an initial step, the ferrous material 10 to be strengthened is placed between the stationary holder 20 and the rotating holder 30. In a next step, the induction coil 50 facilitates heating of the ferrous material 10 to a red hot temperature. In next step, the rotating holder 30 is facilitated with a predefined rotational movement and a predefined axial movement along the central axis of the ferrous material 10. The predefined rotational movement is preferably in a clockwise direction or in a counterclockwise direction. The axial movement is preferably a forward and a backward direction. The rotary and axial movement of the ferrous material 10 causes strengthening of the heated ferrous material 10. Thereafter, the ferrous material 10 is subjected to a cooling media drawn inside the insulating jacket 40. However, it is understood here that the cooling media includes appropriate fluid such as liquid or gas. In the context of the present invention, voltage or current of the induction coil 50, rotary movement of the rotary holder 30, forward/ backward movement of the rotary holder 30 and flow of the cooling media inside the insulating jacket 40 are automatically controlled and programmed to slowly refine an internal structure of the ferrous material 10 thereby resulting into strengthening of the ferrous material 10. The resultant refined internal structure of the ferrous material 10 is of nano meter size, preferably in a range of 10 nm to 20 µm. The resultant ferrous material 10 becomes tough and gains higher strength. However, it is understood here that the process of the present invention is precisely controlled in order to prevent excessive deformation of the ferrous material 10 and damage to the induction coil 50.
However, it is understood here that after completion of the process cycle, the ferrous material 10 is cooled by a gas or a liquid. Further, any secondary process of tempering the ferrous material 10 after the first rotary strengthening deformation may be applied. The ferrous material 10 may be post operated by machining. The ferrous material 10 may be drastically or slowly cooled to room temperature by the presence or absence of the appropriate cooling medium inside the heat insulating jacket 40.
In the context of the present invention, the arrangement 100 and process for strengthening of a ferrous material provide faster strengthening of the ferrous material 10. The arrangement 100 and process for strengthening of a ferrous material facilitate uniform reformation of internal structure of the ferrous material 10. The arrangement 100 and process for strengthening of a ferrous material involve minimum number of elements which reduce the cost of overall process. The arrangement 100 and process for strengthening of a ferrous material facilitates substantially increased strength and toughness to the ferrous material 10. The arrangement 100 and process for strengthening of a ferrous material eliminates formation of by-products.
Example:
Thermo mechanical fatigue testing of the ferrous material-
The ferrous material, Nimonic super alloy in this one illustrative embodiment, was treated in accordance with the process of the present invention and tested on a thermo mechanical fatigue test facility. The results obtained were presented graphically as shown in FIG. 2, wherein the Transient stress ratio represented on Y axis and strain amplitude represented on X axis. The hardening ratio was calculated as per equation (1) below-
.............................. (1)
It was observed that with an increase in the strain amplitude there was an exponential increase in the stress levels after certain strain level indicating the increase in the hardness and strength due to dislocation pile-up.
The foregoing description of specific embodiments of the present invention has been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching.
The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others, skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated.
It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the present invention.
,CLAIMS:We Claim:
1) An arrangement 100 for strengthening of ferrous material comprising:
a ferrous material 10, a stationary holder 20, a rotating holder 30, a heat insulating jacket 40 and an induction coil 50, the ferrous material 10 being positioned between the stationary holder 20 and the rotating holder 30, the insulating jacket 40 enclosing the ferrous material 10, the induction coil 50 being positioned between the stationary holder 20 and the rotating holder 30, the rotating holder 30 having a predefined rotational movement and a predefined axial movement along the central axis of the ferrous material 10.
2) The arrangement 100 as claimed in claim 1, wherein the stationary holder 20 and the rotating holder 30 are respectively made of material selected from metal, non-metal, ceramic and the like.
3) The arrangement 100 as claimed in claim 1, wherein the predefined rotational movement of the rotating holder 30 is in a clockwise direction or a counterclockwise direction.
4) The arrangement 100 as claimed in claim 1, wherein the predefined axial movement of the rotating holder 30 is in a forward direction or a rearward direction.
5) A process for strengthening of ferrous material comprising the steps of:
a) positioning a ferrous material 10 between a stationary holder 20 and a rotating holder 30;
b) heating the ferrous material 10 to a red-hot temperature by an induction coil 50;
c) facilitating a predefined rotational movement and a predefined axial movement to the rotating holder 30 for causing strengthening of the heated ferrous material 10; and
d) facilitating controlled cooling of the ferrous material 10 by introducing a cooling media inside an insulating jacket 40, the insulating jacket 40 enclosing the ferrous material 10, the controlled cooling allowing the ferrous material 10 to have an internal structure of a predefined size.
6) The process as claimed in claim 5, wherein the cooling media is liquid or gas.
7) The process as claimed in claim 5, wherein the predefined size of the internal structure of the ferrous material is in a range of 10 nm to 20 µm.
8) The process as claimed in claim 5, wherein the predefined rotational movement is in a clockwise direction or a counterclockwise direction.
9) The process as claimed in claim 5, wherein the predefined axial movement of the rotating holder 30 is in a forward direction or a rearward direction.