DESC:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2016

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)
TITLE
“NOVEL METHOD FOR RECYCLING SUPERALLOY WASTE”
APPLICANT
(a) Name : Mishra Dhatu Nigam Limited
(b) Nationality : Indian
(c) Address : PO Kanchanbagh, Hyderabad, Telangana – 500058, India

The following specification particularly describes the application and the manner in which it is to be performed.
PRIORITY STATEMENT
The present application hereby claims priority from Indian patent application with the application number 202341031470, filed on 3 May 2023, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD OF INVENTION
The invention relates to the field of resource recycling, in particular to a method for recycling superalloy waste material and converting them into reusage scrap simultaneously and in a short process.

BACKGROUND OF INVENTION
Superalloy refers to a kind of metal material based on iron, nickel and cobalt, which can work for a long time at high temperature above 600? and under certain stress. It has excellent high temperature strength, good oxidation resistance and thermal corrosion resistance, Good fatigue properties, fracture toughness and other comprehensive properties, also known as "super alloys", are mainly used in aerospace and energy fields.
In the casting process of superalloys, a large amount of waste is often generated. These superalloy wastes contain a large amount of valuable metal elements, such as Co, Ni and other rare and precious metal elements, so they have extremely high recycling value.
For these precious metal elements, various recovery processes are proposed in the prior art. At present, the most commonly used methods include hydrometallurgy, pyrometallurgy, and combined hydrometallurgy and pyrometallurgy. Although these methods can realize the recycling of waste alloys to varying degrees, there are also some problems.
Among them, hydrometallurgy is a method of leaching, separating and extracting metals and their compounds from waste alloys using liquid solvents (organic or inorganic solvents). Hydrometallurgy mainly includes the steps of waste pretreatment, waste leaching, solid-liquid separation, solution purification, enrichment and separation, preparation of metals or compounds from solution, and disposal of leaching slag and waste liquid. Therefore, this method has problems such as long process flow, complicated production process, and the need for various chemical reagents.
Therefore, there is an urgent need to find a new method to overcome the existing problems. With this background, the present invention is proposed.

SUMMARY OF THE INVENTION

This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the disclosure. This summary is neither intended to identify key or essential inventive concepts of the disclosure nor is it intended for determining the scope of the disclosure.
The present invention pertains to a novel method for recycling superalloy waste material, comprising the steps of obtaining superalloy waste material generated during the casting processes; and melting the said waste material in VIM to form an ingot refining the said ingot in ESR to prepare high-entropy alloy (HEA), wherein the high-entropy alloy comprises a plurality of elements, adjusting the chemistry and converting the prepared ingot of high-entropy alloys for forging alloys as per industry requirement.

OBJECT OF THE INVENTION
The object of the invention is to disclose a method for recycling superalloy waste material and converting them into reusage scrap simultaneously and in a short process.
DESCRIPTION OF THE INVENTION
In order to solve the above-mentioned technical problems existing in the recycling and utilization of existing superalloy scraps, the present invention provides a new method for recycling superalloy scraps. The method has the advantages that various superalloy wastes can be recycled at the same time, the recycling process is simple and the cycle is obviously shortened, the obtained recycled products have higher utilization value, and the trace elements in the wastes are fully utilized, etc. The problem.
The method for recycling superalloy scraps provided by the invention is to use superalloy scraps as raw materials for preparing high-entropy alloys and obtain high-entropy alloys by melting and casting ingots of reusable scrap, so as to achieve the purpose of recycling superalloy scraps.
In accordance with an embodiment of the present invention, the scrap undergoes Vacuum Induction Melting. VIM is performed in a vacuum chamber or vessel, where the air pressure is significantly reduced to create a controlled atmosphere devoid of oxygen and other gases. It enables melting of wide range of metals present in the scrap.
Based on the industry requirement for forging alloys, the chemistry of ingot is analysed and adjusted. Herein "chemistry is adjusted" refers to manipulation and control of the chemical composition of the molten metal to achieve specific desired properties and characteristics in the final product. This involves careful addition or modification of alloying elements and maintaining the proper balance of constituents during the melting and refining stages.
In accordance with an embodiment of the present invention, the secondary melting is performed on the ingot obtained during primary melting. The secondary melting is performed in ESR furnace. Electroslag Remelting (ESR) is an advanced metallurgical process used for refining and remelting of specialty alloys, particularly large ingots or castings, to improve their quality and performance.
ESR involves melting and refining a consumable electrode. It produces ingots and castings with superior cleanliness, reduced segregation, and improved mechanical properties compared to conventional casting methods.
Those skilled in the art know that traditional alloys are based on one element, and trace performance elements are added to improve the properties of the alloy. However, when there are many impurity elements in the alloy or the impurity elements cannot improve the properties of the alloy, it will also cause the alloy to become inactive. A large number of inclusion phases are produced, thereby reducing the overall properties of the alloy. Therefore, the presence of impurity elements does more harm than good to conventional alloys. This is also the reason why the existing idea of recycling superalloy waste is usually to extract the precious metals and give up the trace elements.
It can be seen that, in the prior art, alloy scrap is usually not selected as the raw material for alloy processing. However, the present invention overcomes this technical prejudice, and proposes to use superalloy scrap as alloy processing raw material.
The recycling of superalloy waste greatly simplifies the recycling process and shortens the recycling cycle; at the same time, the method realizes the simultaneous recovery of all elements including precious metals and trace elements, and greatly improves the recycling value and recycling efficiency of the existing superalloy waste. The key features of the present invention is as follows:
1. Use of Superalloy Waste for High-Entropy Alloy Preparation: The disclosed method proposes using superalloy waste material as raw material for preparing high-entropy alloys. This approach deviates from conventional methods where waste materials are typically processed for recovery of precious metals, often neglecting the trace elements present in the waste.
2. Simultaneous Recycling and Conversion into Reusable Scrap: The invention involves a streamlined process where superalloy waste is directly converted into reusable scrap through VIM and ESR to form high-entropy alloys.
3. Enhanced Utilization of Trace Elements: Unlike traditional recycling approaches that focus primarily on extracting precious metals and disregarding trace elements, the disclosed method aims to fully utilize all elements present in the superalloy waste. By analysing the chemistry and adjusting it by incorporating those elements into high-entropy alloys, the invention maximizes the utilization value of the waste material.
4. Simplified Recycling Process and Shortened Cycle: The described method offers a more straightforward and efficient recycling process compared to existing techniques. By directly repurposing superalloy waste into high-entropy alloys, the recycling cycle is significantly shortened, leading to improved recycling efficiency and reduced environmental impact.
5. Novel Approach to Alloys Processing: The invention challenges technical prejudices by proposing superalloy waste as a viable raw material for alloy processing. This departure from conventional practices underscores the inventive step of the disclosed method.
,CLAIMS:We Claim:
1. A method for recycling superalloy waste material, comprising the steps of:
a. obtaining superalloy waste material generated during the casting processes; and
b. melting the said waste material in VIM to form an ingot
c. refining the said ingot in ESR to prepare high-entropy alloy (HEA), wherein the high-entropy alloy comprises a plurality of elements,
d. adjusting the chemistry and converting the prepared ingot of high-entropy alloys for forging alloys as per industry requirement.
2. The method of claim 1, wherein the superalloy waste material comprises metal elements selected from the group consisting of iron, nickel, cobalt, and other rare and precious metals.
3. The method of claim 1, wherein the recycling process is completed in a shorter timeframe compared to traditional recycling methods..
4. The method of claim 1, wherein ingot obtained from the high-entropy alloys maintains properties suitable for subsequent manufacturing processes.