WO2023062643A1

WO2023062643A1 - Slip planes in metal and mechanical strength in materials

Info

Publication number: WO2023062643A1
Application number: PCT/IN2021/050980
Authority: WO
Inventors: Oded DAHAN; Amnon Regev
Original assignee: Stephen Fernandes
Priority date: 2021-10-13
Filing date: 2021-10-13
Publication date: 2023-04-20

Abstract

The present invention relates to a method for increase or decrease the tensile strength of a work-piece during casting or welding when the material is in liquid/molten state, wherein said method comprising the following steps: making an arrangement for casting mould or welding with electric wires for generating an electromagnetic field; starting casting or welding job process; and applying said electromagnetic field perpendicular to the axis(Depending upon the type of Job) of the casting or welding job. The main objective of the present invention is to provide the workpiece having increased and decreased tensile strength depending upon the requirement when it is manufactured in the presence of electromagnetic field.

Description

SLIP PLANES IN METAL AND MECHANICAL STRENGTH IN MATERIALS

(1) FIELD OF THE INVENTION

The present invention generally relates to the field of improving tensile strength of workpieces. The invention particularly relates to a method for improving tensile strength of a workpiece during casting or welding.

(2) BACKGROUND OF THE INVENTION

The material-treatment processes with which this invention is to be compared include those which are carried out for the purpose of altering and thereby improving characteristics (such as can include structural, magnetic, electrical, optical or acoustical characteristics) of the material being treated. Such processes (e.g., annealing processes) can involve the treatment of materials at temperatures which are less than the melting temperature of the material being treated so that characteristics, such as the strength, durability or hardness, of the material are advantageously affected by the treatment. When steel is produced under usual production heating temperatures of 1200° to 1300° C., finish hot rolling temperatures of 800° to 900° C. and coiling temperatures of 400° to 650° C., its resulting microstructure usually comprises a mixed microstructure of phases of pearlite, bainite and martensite, with a ferrite phase and an austenite phase. It has long been known that the fine structure of this mixed microstructure depends on phase transformation which is brought about by cooling from high temperatures to low temperatures. It is known according to an empirical equation of Hall-Petch that the finer the grains are, the greater the strength, ductility, toughness and fatigue strength of the steel. Accordingly, the constitution of the mixed microstructure is controlled by combination of composition, cooling rate and processing deformation of steel, and the microstructure is so refined that the prescribed characteristics can be obtained. However, methods in which patterns of temperatures and processing are devised for every steel composition have reached their limits. Completely new methods are required.

Electromagnetic stirring is also one of the technique commonly used industrially in the grain refinement of steel and copper alloys. It has also been found to be effective in the grain refinement of Al- and Mg-based alloys. Recent work on electrostatic solidification (free from stirring) and electromagnetic solidification (with stirring) has revealed that melt flow is vital for the attendant equiaxed grain formation due to dendrite fragmentation. Limited evidence suggests that intense electromagnetic stirring beyond a threshold induces nucleation, possibly through the effects of cavitation. An improved understanding of the electromagnetic solidification mechanisms may significantly extend the application of electromagnetic stirring. Electromagnetic stirring both in the mold and in the strand has been applied in billet, bloom, and slab casting. In addition, the electromagnetic brake has also been used in slab casting. These two technologies have been aimed at improved steel quality and/or control of cast structure.

A number of different type of the materials, tools and methods for improving the properties of the metals or steel during the manufacturing are available in the prior art. For example, the following patents are provided for their supportive teachings and are all generally incorporated by reference: A prior art document, US7686895 discloses a method of forming gray iron components includes applying a substantially uniform magnetic field to gray iron. The method also includes heat-treating the gray iron while the gray iron is within the magnetic field. However, the heat-treatment is one of the important step for formation of gray iron.

Another prior art document, US5885370 discloses modification of microstructures of steel undergoing phase transformation in production. This is done by carrying out heat treatment with exposure to a specific magnetic field, followed by advantageous improvement of mechanical properties, as will be further discussed hereinafter.

Yet another prior art document, US7161124 discloses an apparatus includes means for generating a magnetic field within which a workpiece whose characteristics are desired to be altered is positionable. In addition, the apparatus includes means associated with the magnetic field-generating means for thermally treating the workpiece in conjunction with the generated magnetic field so that the characteristics of the workpiece are effected by both the generated magnetic field and the thermal treatment. The means for thermally treating the workpiece can include means for heat-treating the workpiece, means for cooling the workpiece or both heat-treating means and cooling means.

Yet another prior art document, the non -patent literature reference discloses the use of electromagnetic field in twin-roll casting (TRC) of aluminum alloy 5052 (AA5052) for improvement of the microstructure and mechanical properties. A static magnetic field induces an inhibiting effect on the melt in the cast-rolling area and reduces diffusion of the solutes. It also results in more nucleating opportunities and less segregation, thus enhancing the mechanical properties. However, the static magnetic field does not change the orientation of crystal growth and columnar crystals still exist in microstructure. On the other hand, an oscillating magnetic field can refine the suspended particles and induce strong convection (see: Li et al, “Improvement of AA5052 sheet properties by electromagnetic twin-roll casting”; Int J. Adv. Manuf. Technol., 2015, DOI 10.1007/s00170-015-7963-8).

Yet another prior art document, the non -patent literature reference discloses the effect of a high pulsed magnetic field on the tensile properties and microstructure of 7055 alloy were investigated. In the tensile properties test, the pulsed magnetic field was applied to improve the tensile strength and elongation via the magneto plasticity effect (see: Gui- Rong Li et al., “Influence of a high pulsed magnetic field on the tensile properties and phase transition of 7055 aluminum alloy”; Mater. Res. Express 3 106507, 2016, DOI 10.1088/2053-1591/3/10/106507).

Yet another prior art document, the non -patent literature reference discloses results of an experimental study carried out to comprehend the physical, mechanical, and microstructural behavior of cement pastes subjected to static magnetic fields while hydrating and setting. The microstructural characterization makes evident that there are differences in relation to amount and morphology of CSH gel; the amount of CSH is larger and its morphology becomes denser and less porous with higher magnetostatic induction strengths; it also shows the evidence of changes in the mineralogical composition of the hydrated cement pastes. The temperature increasing has no negative effects over the cement paste compressive strength since the magnetostatic field affects the process of hydration through a molecular restructuring process, which makes cement pastes improve microstructurally, with a reduced porosity and a higher mechanical strength (see: Juan J. Soto-Bernal et al., “Effects of static magnetic fields on the physical, mechanical, and microstructural properties of cement pastes”, Advances in materials science and engineering, Vol. 2015, Article ID 934195, DOI: 10.1155/2015/934195 ). Yet another prior art document, the non -patent literature discloses that the surface of 5052 Al alloy plates is severely plastically deformed via multiple impacts by high- velocity tungsten carbide/cobalt (WC/Co) balls in a surface nano-crystallization and hardening (SNH) process. The surface roughness of 5052 Al alloy plates as a function of the impacting ball size and processing time has been evaluated via non-contact 3D profilometry (see: K Dai et al., “Finite element modeling of the surface roughness of 5052 Al alloy subjected to a surface severe plastic deformation process”, Acta Materialia, Vol. 52, No. 20, 2004, pages 5771-5782, DOI:

10.1016/j.actamat.2004.08.031).

Yet another prior art document, the non -patent literature reviews an application of electromagnetic forces in continuous casting mould. Fluid flow characteristics in the mold region play a vital role in deciding the quality of steel produced. The flow pattern of molten metal is accountable for the surface defects, slag entrainment and other surface quality problems. So the mold flow pattern must be restrained to avoid excessive surface velocities, high surface waves, inclusion entrapments and many other problems. Operating conditions that control the mold flow problems include casting speed, submergence depth, nozzle and mold geometry, mold powder, gas injection and electromagnetic forces. The application of magnetic field is an attractive tool as it is noninterfering and can be adjusted during operation. This paper explores different researches presented by researchers in order to study the effect of magnetic field on different quality deciding parameters (see: Mohd Bilal Naim Shaikh et al., “Application of electromagnetic forces in continuous casting mould: A review”, International journal of advances in production and mechanical engineering (IJAPME), Vol. 2, Issue 5, 2016, pages 44-39).

However, above mentioned references and many other similar references has one or more of the following shortcomings: (a) heating step is one of the crucial step in majority of the processes; (b) a pulsed magnetic field is used; (c) a twin-roll casting method is used; (d) not used for simple metallic workpieces; (e) expensive apparatus arrangement; and (f) complex. The present application addresses the above-mentioned concerns and shortcomings (and other similar concerns/shortcomings) with regard to providing an improved workpieces with improved properties.

There remains a constant need in society for a continuous flow of new and innovative novelty method and system for manufacturing workpieces with improved properties. It is in this context, that the subject invention is useful, not only to provide cheap and easy to use but to provide workpieces with improved properties at lower temperature instead of higher temperature.

(3) SUMMARY OF THE INVENTION:

In the view of the foregoing disadvantages inherent in the known types of e-contact book sharing system now present in the prior art, the present invention provides an improved e-contact book sharing system. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved e-contact book sharing system which has all the advantages of the prior art and none of the disadvantages.

It is object of the invention is to provide a method for improving tensile strength of a workpiece during casting or welding, when raw material in in molten/liquid state to increase part life reduced fatigue, wherein said method comprising the following steps: a. making an arrangement for casting or welding with electric wires for generating an electromagnetic field; b. starting casting or welding job process; and c. applying said electromagnetic field perpendicular to the axis of the casting or welding job.

It is another object of the present invention that the method for improving tensile strength of a workpiece during casting or welding. The electromagnetic field is generated by applying electromagnetic field and type of current will be defined by future experiments.

Yet another object of the present invention tha method for improving tensile strength of a workpiece during casting or welding, wherein said workpiece can be either metals, alloy of metals, allow of carbon, or non-metallic materials. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.

(4) BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

Fig. 1 illustrates a casting mould apparatus system according to an embodiment herein. Fig. 2 depicts a welding apparatus system according to an embodiment herein.

Fig. 3 depicts stress strain diagram according to an embodiment herein.

(5) DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that the embodiments may be combined, or that other embodiments may be utilized and that structural and logical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents.

Exemplary embodiments are described with reference to the accompanying drawings. Wherever convenient, the same reference numbers are used throughout the drawings to refer to the same or like parts. While examples and features of disclosed principles are described herein, modifications, adaptations, and other implementations are possible without departing from the spirit and scope of the disclosed embodiments. It is intended that the following detailed description be considered as exemplary only, with the true scope and spirit being indicated by the following claims. Additional illustrative embodiments are listed below.

References will now be made in detail to the exemplary embodiment of the present disclosure. Before describing the detailed embodiments that are in accordance with the present disclosure, it should be observed that the embodiments reside primarily in combinations arrangement of the system according to an embodiment herein and as exemplified in FIGs. 1, 2 and 3.

In the following description, for the purpose of explanation, numerous specific details are set forth in order to provide a thorough understanding of the arrangement of the system according to an embodiment herein. It will be apparent, however, to one skilled in the art, that the present embodiment can be practiced without these specific details. In other instances, structures are shown in block diagram form only in order to avoid obscuring the present invention.

Fluid flow during steelmaking, steel refining and steel casting process is very meaningful to steel quality because it affects other decisive phenomena which include turbulent flow in the molten steel, the transport of bubbles and inclusions, multi-phase flow phenomena, chemical and transport interactions between the steel and the slag, the effect of heat transfer, during these mixing, refining and solidification processes, transport of solute elements and segregation. Numerous work has been done in altering fluid flow pattern and flow characteristics in turn dish to ensure good quality of steel. Electromagnetic forces are an important means to control fluid flow in the mold, combined with other casting conditions, nozzle, and mold geometry. Magnetic field strength offers an effective and an adjustable control parameter that can be varied in real time, and inherently lower turbulent fluctuations. Different magnetic field arrangements have been used to help control the steel flow in continuous casting. Electromagnetic control systems are classified broadly into two types: 1) EMBr, which uses direct current to keep a constant Electro Magnetic field that applies a braking force in proportion to the flow velocity; and 2) Moving field control, which produces a time varying magnetic field to actively drive the flow.

The slip planes are normally planes with the highest density of atoms, i.e., those most closely spaced, and the direction of the slip is the direction in the slip plane that corresponds to one of the shortest lattice translation vectors. Often, this is the direction in which atoms are most closely spaced or dense atoms. In the present invention, the method applies the rule the orientation of these dense places with electrical / magnetic fields mainly in molding operation. By using the method of the present invention, the yield point of the metal limit of the metal can be increased by two times (2A) in certain metals. The present invention can be experimented on various types of metals. The main advantage is with this treatment it does not make the metal brittle by not introducing ex. Carbide (for steel) unlike the conventional method of quenching. This technology can be used in fabrication (welding) to improve the strength of the welding point. The method of the present invention also can be used in non-metal materials. It is also important to note here that as much as tensile strength the workpiece has, it would help in the fabrication.

Fig. 1 illustrates a casting mould apparatus according to an embodiment herein. The casting mould apparatus 100 comprising a mould 102, an electric coil 101 for applying an electromagnetic field to the mould 102, and a powering unit 103 for providing electric current to the electric could 103. In the Fig. 1 embodiment it is shown to cast a pipe 106 from steel. The mould is prepared by filling the mould material thru mould insert 104. Further, the mould also has vent open 105 for allowing either entering air or removing pressure inside the mould. In the casting mould apparatus 100 for preparing the casting a mould 102 with electric wires or electric coil 101 to generate electromagnetic field perpendicular to the axis of the cylindrical steel pipe mould 106 thereby increases the tensile strength. Further, the casting mould apparatus 100 is placed inside the pattern 107, which can be filled with sand or other similar materials.

In another embodiment of the present invention, Fig. 2 depicts a welding apparatus system according to an embodiment herein. The welding apparatus system 200 is depicted which is used for connecting first part 201 with the second part 202. Both the parts are welded at the position 203. The welding is performed in the presence of electric field. The welding apparatus system also includes torch 204 and arrangement 205 for adding the material. The arrangement 205 can be just simple welding rod of the adding material, which is going to be melted and used for the welding. The method for improving tensile strength of a workpiece during casting or welding of the present invention, works well mainly when the material is in the liquid state. Further, higher the tensile strength is helping in fabrication.

Fig. 3 depicts stress strain diagram according to an embodiment herein. Fig. 3 depicts the stress vs. strain diagram 300. This diagram clearly indicates that the tensile strength has increased drastically when the method of the present invention is used while manufacturing or treating a workpiece during casting or welding. The tensile strength can be doubled (2A) when the welding or casting on the workpiece is performed in the presence of electromagnetic field, further the metal will be in the molten state because of which the tensile strength is increased in the workpiece treated according to the present invention.

Above two examples shown above illustrates how the electric field is forced while casting and welding so that most dense planes of atoms is now perpendicular to axis of the moulding / welding job. If the magnetic field is created around the axis of the job i.e. at the circumference the strength can be minimized. In other words if the electric field generated is parallel to the axis of the casting or welding job, minimum tensile strength is achieved. Materials of all kind of metals, alloy of carbon, many kind of non-metal materials, e.g., paper, wood and many others. This method can be applied on any type of casting mould/ contour jobs. This is for better fabrication of Materials.

It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-discussed embodiments may be used in combination with each other. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description.

The benefits and advantages which may be provided by the present invention have been described above with regard to specific embodiments. These benefits and advantages, and any elements or limitations that may cause them to occur or to become more pronounced are not to be construed as critical, required, or essential features of any or all of the embodiments.

While the present invention has been described with reference to particular embodiments, it should be understood that the embodiments are illustrative and that the scope of the invention is not limited to these embodiments. Many variations, modifications, additions and improvements to the embodiments described above are possible. It is contemplated that these variations, modifications, additions and improvements fall within the scope of the invention.

Claims

CLAIMS What is claimed is:

1. A method for improving tensile strength of a workpiece during casting or welding, wherein said method comprising the following steps:

Making an arrangement for casting or welding with electric wires for generating an electromagnetic field;

Starting casting or welding job process; and

Applying said electromagnetic field perpendicular to the axis of the casting or welding job.

2. In general when material is in molten/liquid state, the method for improving tensile strength of a workpiece during casting or welding as claimed in claim 1 , wherein said electromagnetic field is generated by applying electromagnetic field.

3. The method for improving tensile strength of a workpiece during casting or welding as claimed in claim 1 , wherein said workpiece can be either metal, alloy of metals, allow of carbon, or non-metallic materials.

4. The method for improving tensile strength of a workpiece during casting or welding as claimed in claim 1 , wherein said tensile strength of said workpiece is increased up to two times.

5. Reduction in tensile strength (Fig. A, A/4 condition) for better fabrication.

6. Minimum strength for better fabrication.