A laser powder bed fusion system and a process of powder feed in such system

Abstract

The present invention relates to a laser powder bed fusion system (100) and a process of powder feed in such system. The proposed system (100) comprising of light weight laser unit (1) moving in three dimensions above build surface (6) of the build plate (11), a powder feed mechanism (27), (28), (29), (32), (33), and a telescopic arrangement (24). A single or multiple laser unit (1) with its movement offers a large area scan from square millimetre to square meter at speed comparable to speed of optical instrument by maintaining uniform beam shape on build surface with variable beam spot diameter. A powder feed mechanism (27), (28), (29), (32), and (33) utilizes the gravitational force for uniform delivery of powder on the hopper (14) surface. A telescopic arrangement (24) is coupled with the hopper (14) and the dispenser (15) to build the component or powder above or below the reference of build surface (6). Movement of the telescopic arrangement (24) is synchronized with the movement of hopper (14) and dispenser (15), thereby achieving deposition in both upward (25) and downward direction (22).

Description

[0001] A LASER POWDER BED FUSION SYSTEM AND A PROCESS OF POWDER FEED IN SUCH SYSTEM

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a laser powder bed fusion system and a process of powder feed in such system. The proposed system comprising a telescopic arrangement coupled with a hopper and a dispenser facilitates building the component or powder above or below the reference of a build surface of a build plate.

[0004] BACKGROUND OF THE INVENTION

[0005] The designed laser powder bed fusion system is an additive manufacturing system used to build 3D print polymer, metallic and ceramic material. An embodiment for laser powder fusion system based additive manufacturing and in particular to an improved laser powder bed fusion system and apparatus in which laser unit possess three-dimensional movement in build chamber offering varying spot diameter. In other embodiment, it consists of powder feed mechanism using rectangular duct and valves without any pneumatic system. In additions, it offers full utilization of space in laser powder bed fusion system offering higher build height capability.

[0006] Prior Knowledge:

[0007] Laser additive manufacturing is one of the additive manufacturing techniques used to build component in layer-by-layer fashion. Laser additive manufacturing uses laser as a heating source to melt the raw material or feedstock material (available in wire or powder form). Laser additive manufacturing is broadly classified into two categories, i.e., laser directed energy depositions and laser powder bed fusion. Out of two, laser powder bed fusion uses laser beam to selective melt or sinter the metal as per the input coordinate given from geometry or slice. A typical Laser Powder Bed Fusion system consists of build chamber, powder storage tank or dispenser, recoater, and laser unit or optical unit (single or multiple beam) may or may not be with gas flow and buildplate heating unit.

[0008] Standard Laser Powder Bed Fusion process involves: (i) spreading of powder on the build surface in form of thin powder layer (ii) laser scan to melt or sinter the laid powder (iii) lowering of build surface or plate or platform as per layer thickness, and again steps (i) to (iii) is repeated to build a three-dimensional component. During the melting or sintering process, single or multiple laser beam is used to scan the build surface to melt or sinter the powder. This laser scan is performing either using a galvanometer or by moving the optical unit relative to the build surface or both keeping the beam spot diameter and distance between the build surface and laser source constant throughout the building process. In addition, the maximum height of built is not more than the height of build chamber, which is achieved by lowering the build surface or increasing the distance between laser source and build surface. Further, the amount of powder required to build the component is stored in hopper or deliver through powder feed mechanism to hopper or powder tank.

[0009] Drawbacks connected with hitherto known Processes / de vices:

[0010] Available laser powder bed fusion system utilizes galvanometer or moving optics unit to scan the build surface. This galvanometer unit has limitation in scaling up the scanning area due to limitation posed by optical design, while the moving optics unit is bulky in construction and has limitation due to mass inertia. Also, the incident laser beam is not normal to the build surface limiting the scaling of build volume. Both units involve several components, such as - reflecting mirrors, laser source, collimators, optical lens, laser source casing or cover, etc. The combination of all these components limits the movement of laser energy unit or galvanometer or optical unit in terms of degree of freedom, speed, weight, and scalability of the unit. Thus, there is a need of lightweight unit and system offering higher degree of freedom for movement of laser head or moving optics along with reduced weight offering ease of handling.

[0011] In another observation, the build rate in laser powder bed fusion system is dependent on process parameter (such as - number of lasers, laser power, scan speed, overlap or hatch spacing and layer thickness) and beam spot diameter. Size of beam spot diameter on build surface governs the energy density (controlling the build rate) and feature size during depositions.

[0012] Thus, a varying beam spot diameter during the depositions can alter the depositions rate and feature size as per the requirements.

[0013] But, in the present laser powder bed fusion system, the beam spot diameter is kept constant throughout the deposition process.

[0014] Thus, there is need of laser powder bed fusion offering variable beam spot diameter during the depositions, which yield a varying deposition rate as well as requisite feature size.

[0015] It is observed that the weight or amount of powder required to build a component is substantially equal or higher than the weight of component to be build and, same amount of powder is stored in hopper. This leads to requirement of volume of hopper equal to greater than the volume of component to be printed. It also adds the weight of powder on hopper leading to requirement of heavy structure of hopper to sustain the applied weight of powder onto it.

[0016] In addition, the movement of hopper is the equal and opposite of movement of build plate during depositions. To overcome this, a powder feed mechanism is deployed using pneumatic control system or gear controlled to delivered powder on build surface or hopper surface using single or multiple powder. However, the pneumatic system or gear-controlled system offers lesser uniformity in powder distribution and create turbulence in powder while delivering. In addition, this method leads to increased printing time as powder delivery starts after laser scanning followed by movement of build plate and subsequently powder spreading by recoater. In addition, the powder spreading is performed on whole build surface irrespective of build size leading to requirement of large amount of powder irrespective of size of print component.

[0017] In addition, the maximum build height is determined by either the lowered height of the build chamber or the raised height of the laser head concerning the build surface. It offers a constrained on maximum achievable build height of a laser powder bed fusion system. Therefore, there is need of laser powder bed fusion system offering effective utilization of volume of build chamber for increased build height.

[0018] OBJECTS OF THE INVENTION

[0019] In view of the foregoing limitations inherent in the state of the art, some of the objects of the present disclosure, which at least one embodiment herein satisfy, are listed herein below.

[0020] The object of the present invention is to develop a system of light-weight laser unit or laser beam delivery unit with less number mechanical or optical component offering higher degree of freedom to moving optical unit ensuring incident laser beam normal to build surface.

[0021] Another object of the present invention is to provide such system capable of offering speed comparable to that of present optical system or galvanometer.

[0022] Another object of the present invention is to propose a device and process to vary the beam spot diameter on the build surface as per need of the depositions rate and feature size as demanded.

[0023] Yet another object of the present invention is to design a powder feed mechanism offering limited load on hopper and offering minimum movement to hopper unit. Yet another object of the present invention is to propose a system and process to control the height by combining both upward movement of powder storage unit and downward movement of build-plate. This will offer a system to utilize full volume of build chamber above and below the build surface.

[0024] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.

[0025] SUMMARY OF THE INVENTION

[0026] First aspect of the invention is to produce a light-weight system of laser source unit without galvanometer or any reflecting mirror, that offers a three-dimensional movement to laser source unit within the build volume with a scan speed comparable to that of optical sources such as galvanometer or reflecting mirrors. This system consists of refractive mirrors and laser delivery fiber integrated with robotic arm specially design / modified as per the requirement to keep the incident laser beam normal to build surface.

[0027] Secondly, this system is capable of varying beam spot diameter at the build surface as per the demand. Varying beam spot diameter is achieved by movement of refractive optics as per input given by user to achieve desired build rate.

[0028] Third aspect of the invention consist of a method of powder feed mechanism on to the hopper. This system utilizes gravitational force to feed the calibrated powder on the hopper. Before the powder spreading, the calibrated powder from the powder storage tank is fed through the powder delivery valve and distributed on the hopper top surface by a rectangular duct with or without a louvers through the area control valve utilizing gravitational force followed by spreading of the powder on build surface by the recoater. The recoater travel or displacement on the build surface is adjusted. In other operations, the area control valve controls the area of opening of powder delivery valve and opening and closing of the powder delivery valve feeds the powder on hopper top surface. This powder feed mechanism performs its operation (delivery of powder on to hopper top surface) during laser scanning yielding the reduced printing time.

[0029] Fourth aspect of the invention consists of a system and a process to build a component or sample below and above the build surface in order to utilize the full volume of the system.

[0030] In first step, this system utilizes the build volume below the build surface to print component of the build surface by achieving the downward movement of the build surface. In second step, this system utilizes the volume above the build surface to print component on the build surface by achieving the upward movement of specially developed powder dispenser and recoater unit.

[0031] The new result flowing from the new finding:

[0032] The developed laser powder bed system consists of single or multiple light weight laser units (output power ranging from 50 W to 2 kW), the build platform having an area range from few square milli meter to square meter, the modified single or multiple light weight arrangement of robotic arms or manipulators, the scanning build area up to a meter by meter range (per arm) with a maximum achievable speed of 2.5 m / s, the built height nearly equal to additions of download movement of the build plate from the build surface (~ hundreds microns to mm) and upward movement of hopperdispenser unit (~ hundreds of microns to mm), the beam spot diameter variation between 0.1 mm to 5 mm on build surface, and the overall build volume from 10 mm3to 1 m3. The integration of moving laser energy unit and robotic arm offers 3D movement to laser unit or allied laser delivery system. In additions, this system offers a powder feed mechanism on hopper surface leading to variable powder spread area as per size of component to be print and it also leads to reduced volume and movement of hopper. For example, the developed system offers several enhancements compared to commercially available machines across various parameters, such as the use of moving optics and robotics assembly instead of a galvanometer, which has reduced the weight. The laser source unit in the proposed system is notably lighter, weighing less than 2 kg compared to the galvanometer-based unit weighing 3 kg in commercially available machines.

[0033] Additionally, it has reduced the cost of the laser head unit by 60-65% compared to galvanometer-based units. Significant improvements are evident in the spatial requirements of the proposed system. For print a component of 250 mm height, it requires less than 150 mm of space below the reference plane, reducing the overall footprint due to its ability to build components in both directions: 150 mm below and 100 mm above the reference plane.

[0034] Moreover, above the reference plane, space requirements are variable, reduced by 200 mm, due to a modified robotic arm / manipulator offering enhanced freedom. This adaptation allows for better space utilization, with 30- 50% of the area above the reference plane being utilized for component building, which represents previously unused volume in commercially available systems.

[0035] Additionally, the proposed system demonstrates advancements in weight management, with the powder hopper's weight reduced by 45-55%, facilitated by a more efficient and cheaper powder feeding mechanism. The developed machine delivery powder on hopper plate during the printing of previous layer and it takes 5 to 10 seconds including both printing and spreading time. Which saves powder delivery time is saved 2 - 3 seconds after every layer as compared to commercially available machine for same print volume. These improvements collectively enhance the efficiency and performance of the proposed system, making it a promising advancement in additive manufacturing technology. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0036] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0037] Fig. la illustrates the laser energy unit (1) at position 1.

[0038] Fig. lb illustrates the laser energy unit (1) at position 2.

[0039] Fig. 2 illustrates the powder feed mechanism.

[0040] Fig. 3a illustrates the Schematic of laser powder bed fusion system (100) without laser energy unit (1).

[0041] Fig. 3b illustrates the Schematic of laser powder bed fusion system (100) with laser energy unit (1).

[0042] Fig. 4a illustrates the powder bed fusion system (100) with downward build volume.

[0043] Fig. 4b illustrates the powder bed fusion system (100) with upward build volume.

[0044] Fig. 5 illustrates the powder bed fusion system (100) with telescopic arrangement moving in upward direction: (I) Initial stage, (II) Intermediate of Final stage.

[0045] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. Throughout the drawings, it should be noted that reference numbers are used to depict the same or similar elements, features, and structures.

[0046] DETAIL DESCRIPTION OF THE PRESENT INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS OF PREFERRED EMBODIMENTS

[0047] In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to one skilled in the art that embodiments of the present disclosure may be practiced without some of these specific details.

[0048] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention.

[0049] The terms and words used in the following description and claims are not limited to the bibliographical meanings but are merely used to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention.

[0050] If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.

[0051] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

[0052] The present disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the present disclosure to those of ordinary skill in the art.

[0053] The present invention relates to a laser powder bed fusion system and a process of powder feed in such system.

[0054] The present invention relates to a laser powder bed fusion system involving a laser or laser beam delivery unit integrated with modified robotic arm or manipulator possessing a lightweight system and 3D movement to the laser delivery unit over the build surface area within a build volume. This laser beam delivery unit consists of beam delivery fiber and refractive optics (instead of galvanometer or a combination of reflective and refractive optics) integrated with the modified robotic arm or manipulator offering a lightweight system and ease of maintaining desired accuracy during additive manufacturing. For example, the weight of a designed laser unit or laser beam delivery unit consists of weight of refractive optics and mounting units without any galvanometer or reflecting mirrors.

[0055] In the preferred embodiment, the designed system offers variable beam spot diameter on build surface by varying the distance between laser delivery unit and build surface during the depositions process as per the need. For example: the beam spot diameter is 0.2 mm during the building of some finer features, and it can be varied to 5 mm while building of the bulk structures achieving the need of higher depositions. This can be interchangeable for any value within the range of beam spot diameter irrespective of layer as per the need. This variation in beam spot diameter is achieved by varying the distance between the build surface and lower edge of moving laser unit or laser beam delivery unit.

[0056] In the present invention, a method of powder feed mechanism has been deployed on to the hopper. This mechanism involves a powder storage unit, rectangular delivery duct, area control valve, and powder delivery valve. The area control valve and powder delivery valve are open and closed by electrical motor or solenoid valve. For example, the amount of powder equal to the volume of a layer is calibrated and delivered by a rectangular duct on to the hopper surface using weight of powder. Subsequently, the recoater arm is arranged by adjusting recoater displacement in such a way that it will uniformly distribute the delivered powder from the hopper surface to the build surface in the requisite scan area. This leads to fixing or no movement of hopper plate during deposition or printing of component below the reference level of build surface. In addition, the powder delivery valve performs its operation (opening and closing) during laser scanning to reduce the printing time. In the preferred embodiment, the volume above and below the build surface is effectively utilized by integrating a movement of combined unit of build surface, dispenser, hopper, and recoater arm on both direction of the build surface at reference position.

[0057] The proposed system consists of a hopper, a dispenser, and a recoater along with a special telescopic arrangement at build surface to achieve the desired upward and downward motion using a driving mechanism, such as stepper motor, servomotor, linear motor, etc. for effective utilization of space.

[0058] For example, the build plate moves downward by an amount nearly equal to the layer thickness after laser scanning of a powder layer over the build surface. Subsequently, a new layer of powder is spread onto the build plate and laser scanning is performed on the build surface according to the design. This process is repeated, with the build plate descending further, incrementing the height of the built object with each iteration.

[0059] In addition, after scanning a particular layer of powder on the build surface, the build plate remains constant and the members attached to the telescopic arrangement such as the hopper, the dispenser, and the recoater will move upward equivalent to height of the layer thickness. This upward movement of telescopic arrangement and layer additions lead to building of component above the build surface. Thus, the developed system and process utilizes the build volume of laser powder bed system very effectively.

[0060] Figure 1 (a) depicts the preferred embodiment of a laser powder bed fusion system (100) at position 1, at initial stage comprising laser energy unit (1) which consist of laser delivery cable or fiber (2), refractive mirrors (3), mounting arrangement (4), and modified robotic arm (5) (single or multiple).

[0061] The laser energy unit (1) is integrated in such a way that it can scan the build surface (6) along the direction (7), (8) & (9) with a beam spot diameter (10). In addition, the modified robotic arm (5) is specially designed light weight arms (made up of metal or plastic or carbon fiber or similar light weight material capable of withstanding temperature up to 1400°C without melting) and driven by electrical device such as stepper motor, servomotor, linear motor, etc. offering a speed equal to scanning speed equal to the speed offered by an optical instrument or galvanometer.

[0062] Figure 1(b) depicts the laser energy unit (1) at different location (position 2) with a different beam spot diameter (10) on build surface (6). The change in beam spot diameter (10) can be seen in Figure 1 (a) and (b). This change in location of laser energy unit (1) and beam spot diameter (10) is programmed controlled as defined by the user or as per the need.

[0063] Figure 2 illustrates the arrangement for performing the powder feed mechanism. Figure 3 illustrate the laser powder bed fusion system (100) (a) without laser energy unit (1) and (b) with the laser energy unit (1) at initial stage of powder spreading on the build plate (11) having the build surface (6) thereupon, using the recoater arm (12).

[0064] Initially, the powder is calibrated (volume of powder is equal to volume of powder required for a layer) and delivered powder (30) to the hopper’s (14) top surface (31) from the powder storage tank (28) through the rectangular delivery duct (27) without any pneumatic system or gear arrangement (referring to Figure 2). The area of powder passage in delivery duct (27) is controlled by area-controlled valve (32) and the delivery of powder is controlled by the powder delivery valve (33) (referring to Figure 2).

[0065] During the powder spreading (referring to Figure 3a-b), the build plate (11) goes downward direction (22) with respect to the build surface (6) to a height equal to the height of the powder layer (13). Then, the recoater arm (12) uniformly spreads the powder on the build plate (11) from the top surface (31) of the hopper (14). The recoater arm (12) is connected to a driving unit (21) mounted on the hopper (14) and the leftover extra powder during spreading is collected into the dispenser (15). During a laser scanning stage, the laser energy unit (1) selectively melts the spreader powder layer (13) on the build plate (11). The dispenser (15), the build plate (11) and the hopper (14) are connected to a driving unit as (17), (18) and (19) respectively to a common or different driving unit (20). This driving unit (20) is program controlled.

[0066] Further, this combination of layer by layer spreading and melting process endures utilization of full capacity of the downward build volume (16) below the build surface (6) as shown in Figure 4 (a-b). Figure 4a illustrates the schematic of the laser powder bed fusion system (100) with downward build volume (26).

[0067] Figure 4b illustrates the schematic of the laser powder bed fusion system (100) with upward build volume (26). This is achieved by moving the hopper (14) and dispenser (15) in the upward direction (25) equal to the height of the layer thickness (13). The layer-by-layer depositions in upward direction (25) lead to build volume (26) above the initial reference (22) of build plate as shown in (I) initial and (II) intermediate or final stage as illustrated in Figure 5.

[0068] To control the spreading of the powder while spreading through the recoater (12), a telescopic arrangement (24) is attached between the hopper (14) and the dispenser (15) which moves in the upward direction (25) equal to the height of the powder layer thickness (13) as illustrated in Figure 5.

[0069] In the preferred embodiment, the vertical motion of the build plate is not carried to build the component above the build surface.

[0070] The telescopic arrangement (24) is attached to two sides of the build plate (11), and in between the hopper (14) and the dispenser (15). In addition, the positions of telescopic arrangement (24) in Figure 5 are representative only, this telescopic arrangement (24) can be mounted along with build plate to avoid incongruity structure around the build surface.

[0071] Movement of the telescopic arrangement (24) is synchronized with the movement of the hopper (14) and the dispenser (15), thereby achieving deposition on upward direction (25).

[0072] Examples: This invention is applied to print or build 3D metal components using designed laser powder bed fusion system. Prior to laser scan, austenitic stainless steel (SS 304L) powder is loaded into hopper surface through powder delivery system and build plate goes down (nearly equal to layer thickness) and powder spreading is carried out using recoater arm.

[0073] Further, moving laser unit selectively scans and melts the powder and subsequently solidification of melted powder leads to consolidation of powder into solidified layer as per the cross-section of 3D component. This layer by layer spreading of powder, melting and solidification lead to consolidation of powder into 3D component by deploying above developed system.

[0074] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.

[0075] The present disclosure is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the present disclosure when combined with information and knowledge available to the person having ordinary skill in the art and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter. ADVANTAGES OF THE INVENTION

[0076] The present invention is about a laser powder bed fusion system that consists of light weight laser energy source moving in three dimensions and telescopic arrangement. The present invention offers following advantages: i. Light weight laser source unit provides the possessing capability of three-dimensional movement in build volume. In addition, it offers a large scan area ranging from square mm to square meter with a speed substantial equal to optical scan speed. ii. A device that offers variable beam spot diameter during in-situ depositions offering varying depositions rate and feature size. iii. Powder feed mechanism offers reduced size of hopper volume and reduced printing time. Further, it makes print size independent of powder stored in hopper. iv. A system capable of depositing material in the upward and downward direction of build surface reference as per user need. It offers full utilization of space in laser powder bed fusion system offering higher build height capability.

Claims

Claims:

1. A laser powder bed fusion system (100) for depositing component on a surface of a build plate, characterised in that said system (100) comprises: one or more laser energy units (1) consisting of a laser delivery cable or fiber (2), a refractive mirror (3) mounted with a mounting arrangement (4) and one or more robotic arms (5), wherein the laser energy unit (1) being configured to scan a build surface (6) on the build plate (11) upon which the component or powder (30) being spread along different directions (7, 8, 9) having variable beam spot diameter (10); a hopper (14) with a top surface (31) upon which the powder (30) being delivered from a powder storage tank (28) through a rectangular delivery duct (27), wherein the delivery duct (27) being controlled by an area- controlled valve (32) and the delivery of the powder (30) being controlled by a powder delivery valve (33); a dispenser (15) to collect the leftover extra powder during spreading; a recoater arm (12) mounted on the hopper (14) via a driving unit (21) to spread the powder from the hopper surface (31) onto the build surface (6) of the build plate (11) in the requisite scan area, wherein the laser energy unit (1), the dispenser (15), the build plate (11) and the hopper (14) being connected to a base driving unit (20) via respective separate driving units (17-19); a telescopic arrangement (24) attached between the hopper (14) and the dispenser (15) on both sides of the build plate (11) configured to move in an upward direction (25) equal to the height of the powder layer thickness (13) on the build plate (11), wherein layer-by layer powder deposition in the upward direction (25) being configured to build volume (26) above or below an initial reference (22) surface of the build plate (11) by integral movement of the build surface (6), the dispenser (15), the hopper (14), and the recoaterarm (12) on both up and down direction of the build surface (6) at reference position.

2. The system as claimed in claim 1, wherein the variation in beam spot diameter (10) being achieved by varying the distance between the build surface (6) and the lower edge of the moving laser unit (1).

3. A process of powder feed in a laser powder bed fusion system (100) as claimed in claim 1, said process comprises steps of: calibrating and delivering powder (30) to a top surface (31) of a hopper (14) from a powder storage tank (28) through a delivery duct (27), spreading the powder on a build plate (11) from the top surface (31) of the hopper (14) by a recoater arm (12) mounted on the hopper (14), wherein the build plate (11), the hopper (14), a dispenser (15) and a laser energy unit (1) being connected to a common base driving unit (20), moving the build plate (11) to downward direction (22) with respect to its build surface (6) to a height equal to the height or thickness of the powder layer (13), melting the powder layer (13) on the build plate (11) by the laser energy unit (1), spreading and melting the powder layer by layer with downward movement of the generated build volume (16) below an initial reference surface (22) of the build plate (11), moving the hopper (14) and the dispenser (15) in the upward direction (25) equal to the thickness of the powder layer (13), controlling the spreading of the powder through the recoater arm (12) with the aid of a telescopic arrangement (24) attached between the hopper (14) and the dispenser (15) on both sides of the build plate (11), wherein thetelescopic arrangement (24) moves in upward direction (25) equal to the thickness of the powder layer (13), and depositing powder in layer-by-layer fashion to build volume (26) above the initial reference surface (22) of the build plate (11).

4. The process as claimed in claim 3, wherein the beam spot diameter (10) being kept constant or varied based on requirement throughout the respective powder deposition performance.

5. The process as claimed in claim 3, wherein movement of the telescopic arrangement (24) being synchronized with the movement of hopper (14) and dispenser (15), thereby achieving deposition on upward direction (25).

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