The Experts below are selected from a list of 480 Experts worldwide ranked by ideXlab platform

C F Cheung - One of the best experts on this subject based on the ideXlab platform.

  • an nc tool path translator for virtual machining of precision optical products
    Journal of Materials Processing Technology, 2003
    Co-Authors: W Lee, D Gao, C F Cheung
    Abstract:

    Abstract In this paper, a virtual machining system (VMS) for the ultra-precision diamond turning is presented, and the NC tool path translator function module of the VMS is discussed. The developed VMS is based on the NC program not as some commercial CAD/CAM software which is based on the cutter location DATA file. In the VMS, the virtual machine tool is controlled through the NC program used by the actual machine tool. The NC tool path translator consists of accidence analysis, lexical-analyzer, grammar and semantic parse, driving code generator, etc. The manufacture of a Mould Insert for a diffractive lens was used as a case study to illustrate the performance of the developed VMS.

  • An NC tool path translator for virtual machining of precision optical products
    Elsevier, 2003
    Co-Authors: W Lee, Gao D, C F Cheung
    Abstract:

    In this paper, a virtual machining system (VMS) for the ultra-precision diamond turning is presented, and the NC tool path translator function module of the VMS is discussed. The developed VMS is based on the NC program not as some commercial CAD/CAM software which is based on the cutter location DATA file. In the VMS, the virtual machine tool is controlled through the NC program used by the actual machine tool. The NC tool path translator consists of accidence analysis, lexical-analyzer, grammar and semantic parse, driving code generator, etc. The manufacture of a Mould Insert for a diffractive lens was used as a case study to illustrate the performance of the developed VMS.Department of Industrial and Systems Engineerin

W Lee - One of the best experts on this subject based on the ideXlab platform.

  • an nc tool path translator for virtual machining of precision optical products
    Journal of Materials Processing Technology, 2003
    Co-Authors: W Lee, D Gao, C F Cheung
    Abstract:

    Abstract In this paper, a virtual machining system (VMS) for the ultra-precision diamond turning is presented, and the NC tool path translator function module of the VMS is discussed. The developed VMS is based on the NC program not as some commercial CAD/CAM software which is based on the cutter location DATA file. In the VMS, the virtual machine tool is controlled through the NC program used by the actual machine tool. The NC tool path translator consists of accidence analysis, lexical-analyzer, grammar and semantic parse, driving code generator, etc. The manufacture of a Mould Insert for a diffractive lens was used as a case study to illustrate the performance of the developed VMS.

  • An NC tool path translator for virtual machining of precision optical products
    Elsevier, 2003
    Co-Authors: W Lee, Gao D, C F Cheung
    Abstract:

    In this paper, a virtual machining system (VMS) for the ultra-precision diamond turning is presented, and the NC tool path translator function module of the VMS is discussed. The developed VMS is based on the NC program not as some commercial CAD/CAM software which is based on the cutter location DATA file. In the VMS, the virtual machine tool is controlled through the NC program used by the actual machine tool. The NC tool path translator consists of accidence analysis, lexical-analyzer, grammar and semantic parse, driving code generator, etc. The manufacture of a Mould Insert for a diffractive lens was used as a case study to illustrate the performance of the developed VMS.Department of Industrial and Systems Engineerin

Willey Yun Hsie Liew - One of the best experts on this subject based on the ideXlab platform.

  • WTC2005-63952 WEAR OF COATED CARBIDE TOOLS IN THE ULTRA-PRECISION MACHINING OF STAINLESS STEEL
    2020
    Co-Authors: Willey Yun Hsie Liew, X. Ding
    Abstract:

    ABSTRACT Ultra-precision machines are widely used to turn aspherical profiles on Mould Inserts for the injection Moulding of optical lenses. During turning of a profile on a stainless steel Mould Insert, the cutting speed reduces significantly to 0 as the cutting tool is fed towards the center of the machined profile. This paper reports on experiments carried out to study the wear of uncoated, PVD-coated and CVD-coated carbide tools in the ultra-precision machining of STAVAX (modified AISI 420 stainless steel) at low speeds. KEY WORDS: Carbide tool; machining, lubricant, steel, wear INTRODUCTION Many Mould Inserts used for the injection Moulding of optical lenses are fabricated from stainless steel with hardness of between 40 HRC and 55 HRC

  • wear characteristics of pcbn tools in the ultra precision machining of stainless steel at low speeds
    Wear, 2003
    Co-Authors: Willey Yun Hsie Liew, K A Ngoi
    Abstract:

    Polycrystalline cubic boron nitride (PCBN) cutting tools are widely used in the ultra-precision machining of stainless steel Mould Inserts for the injection Moulding of optical lenses. During the machining of a spherical or an aspherical profile on a Mould Insert, the cutting speed reduces significantly to approximately 0 as the cutting tool is fed towards the centre of the machined profile. This paper will report on experiments carried out to investigate the wear of various grades of PCBN tool in the ultra-precision machining of STAVAX (modified AISI 420 stainless steel) at low speeds. In the initial stage of machining, fine-scale cavities were formed on the rake face and as such, the damaged surface acted like a chip breaker and thus as a preferential site for crack initiation. Once a crack was initiated, it propagated along the grain boundaries leading to intergranular fracture. The experimental results show that the formation and extent of the surface fracture are greatly dependent on the cutting forces and the severity of abrasion on the rake face which are governed by the cutting temperature. The porosity, ductility and the bonding strength of the grains in the tool, apart from its thermal conductivity appear to have major influences on the fracture resistance of the tool.

K A Ngoi - One of the best experts on this subject based on the ideXlab platform.

  • wear characteristics of pcbn tools in the ultra precision machining of stainless steel at low speeds
    Wear, 2003
    Co-Authors: Willey Yun Hsie Liew, K A Ngoi
    Abstract:

    Polycrystalline cubic boron nitride (PCBN) cutting tools are widely used in the ultra-precision machining of stainless steel Mould Inserts for the injection Moulding of optical lenses. During the machining of a spherical or an aspherical profile on a Mould Insert, the cutting speed reduces significantly to approximately 0 as the cutting tool is fed towards the centre of the machined profile. This paper will report on experiments carried out to investigate the wear of various grades of PCBN tool in the ultra-precision machining of STAVAX (modified AISI 420 stainless steel) at low speeds. In the initial stage of machining, fine-scale cavities were formed on the rake face and as such, the damaged surface acted like a chip breaker and thus as a preferential site for crack initiation. Once a crack was initiated, it propagated along the grain boundaries leading to intergranular fracture. The experimental results show that the formation and extent of the surface fracture are greatly dependent on the cutting forces and the severity of abrasion on the rake face which are governed by the cutting temperature. The porosity, ductility and the bonding strength of the grains in the tool, apart from its thermal conductivity appear to have major influences on the fracture resistance of the tool.

Reynaerts Dominiek - One of the best experts on this subject based on the ideXlab platform.

  • Shaping Soft Robotic Microactuators by Wire Electrical Discharge Grinding
    'MDPI AG', 2020
    Co-Authors: Milana Edoardo, Ellotti Mattia, Gorisse Enjami, Ju Qia, De Volde Michaël, Reynaerts Dominiek
    Abstract:

    Inflatable soft microactuators typically consist of an elastic material with an internal void that can be inflated to generate a deformation. A crucial feature of these actuators is the shape of ther inflatable void as it determines the bending motion. Due to fabrication limitations, low complex void geometries are the de facto standard, severely restricting attainable motions. This paper introduces wire electrical discharge grinding (WEDG) for shaping the inflatable void, increasing their complexity. This approach enables the creation of new deformation patterns and functionalities. The WEDG process is used to create various Moulds to cast rubber microactuators. These microactuators are fabricated through a bonding-free microMoulding process, which is highly sensitive to the accuracy of the Mould. The Mould cavity (outside of the actuator) is defined by micromilling, whereas the Mould Insert (inner cavity of the actuator) is defined by WEDG. The deformation patterns are evaluated with a multi-segment linear bending model. The produced microactuators are also characterised and compared with respect to the morphology of the inner cavity. All microactuators have a cylindrical shape with a length of 8 mm and a diameter of 0.8 mm. Actuation tests at a maximum pressure of 50 kPa indicate that complex deformation patterns such as curling, differential bending or multi-points bending can be achieved.status: publishe

  • Shaping Soft Robotic Microactuators by Wire Electrical Discharge Grinding
    'Organisation for Economic Co-Operation and Development (OECD)', 2020
    Co-Authors: Milana Edoardo, Ellotti Mattia, Gorisse Enjami, Ju Qia, De Volde Michaël, Reynaerts Dominiek
    Abstract:

    Inflatable soft microactuators typically consist of an elastic material with an internal void that can be inflated to generate a deformation. A crucial feature of these actuators is the shape of ther inflatable void as it determines the bending motion. Due to fabrication limitations, low complex void geometries are the de facto standard, severely restricting attainable motions. This paper introduces wire electrical discharge grinding (WEDG) for shaping the inflatable void, increasing their complexity. This approach enables the creation of new deformation patterns and functionalities. The WEDG process is used to create various Moulds to cast rubber microactuators. These microactuators are fabricated through a bonding-free microMoulding process, which is highly sensitive to the accuracy of the Mould. The Mould cavity (outside of the actuator) is defined by micromilling, whereas the Mould Insert (inner cavity of the actuator) is defined by WEDG. The deformation patterns are evaluated with a multi-segment linear bending model. The produced microactuators are also characterised and compared with respect to the morphology of the inner cavity. All microactuators have a cylindrical shape with a length of 8 mm and a diameter of 0.8 mm. Actuation tests at a maximum pressure of 50 kPa indicate that complex deformation patterns such as curling, differential bending or multi-points bending can be achieved

  • Manufacturiing of uIM Mould Inserts with AMed Cooling Channels
    Singapore, 2015
    Co-Authors: Qian Jun, Kempen Karolien, Wang Jun, Yang Carry, Welkenhuyzen Frank, Vanderauwera Wouter, Kruth Jean-pierre, Reynaerts Dominiek
    Abstract:

    The Selective Laser Melting (SLM) process is one of the proven key 3D printing technologies for producing complex and micro metallic structures, for instance conformal cooling channels for micro-injection molding. In micro injection molding, the conformal channels enables a controlled heating/cooling of the molded part, resulting in a better thermal management of the micro injection Moulding (µIM). Since a part produced by SLM is a monolithic component, the way to check the quality of the internal features should be a non-destructive method, and Computed Tomography (CT) is an ideal solution for it. In this research, a Mould Insert for micro injection Moulding with conformal is first produced through Selective Laser Melting. The internal features in the blank are then examined by CT-metrology and the cavities and features down to 25µm (aspect ratio of 30) of the mold Insert are finished by micro-EDM.status: publishe

  • A holistic approach for μEDM milling on SLMed steel
    2014
    Co-Authors: Qian Jun, Kempen Karolien, Wang Jun, Yang Carry, Reynaerts Dominiek
    Abstract:

    Maraging steel Mould Insert blanks have been produced selective laser melting (SLM) and then they are further processed by micro electrical discharge machining μEDM) to generate the desired features. In order to reach high efficiency manufacturing of micro features, a holistic approach with this micro-sparking technique is pursued at University of Leuven. Accordingly various upgrading has been carried out on a commercial SARIX® machine, including monitoring and controlling of the stability of the sparking process (gap variation and energy distribution etc.), wear compensation of the tool-electrode, and on-machine metrology. Preliminary experiments have been carried out with promising results in terms of production time and shape accuracy.status: publishe