The Experts below are selected from a list of 18504 Experts worldwide ranked by ideXlab platform
Shaochuan Feng - One of the best experts on this subject based on the ideXlab platform.
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surface quality evaluation of single crystal 4h sic wafer machined by hybrid laser waterjet comparing with laser machining
Materials Science in Semiconductor Processing, 2019Co-Authors: Shaochuan Feng, Chuanzhen Huang, Jun WangAbstract:Abstract Single crystal silicon carbide (SiC), as a 3rd generation semiconductor material, has a wide application range and development prospect, especially in some key fields such as defense and aerospace industries. It's a typical difficult-to-machine and hard-brittle material due to its high hardness and brittleness. A hybrid laser-waterjet Micromachining technology was employed to implement near damage-free and high-efficient Micromachining of single crystal SiC. The workpiece material is heated by laser to a temperature near but below its melting point. The material is under an extremely “softened” but still solid status. A waterjet is applied off-axially to expel the heating-softened material and cool the material to eliminate thermal damage. It combines the advantages of laser processing with those of waterjet cutting. Moreover, it's a green machining approach, which is pollution-free and recyclable. In the present study, the surface quality of single crystal 4H-SiC machined by the hybrid laser-waterjet is evaluated and compared with that machined by laser. Among the wafers respectively machined by laser, under-water laser, waterjet-assisted laser and the hybrid laser-waterjet, the one machined by the hybrid laser-waterjet is with the best surface quality. Its cut boundaries between the machined area and the unmachined area are clear, the cut edges are straight, also the cut sides are clean. On the contrary, there is severe thermal damage along the cut edges and cut sides of laser machining. The microgrooves obtained from the hybrid laser-waterjet Micromachining are with V-shaped cross-sections and the transition between the cut edge and the unmachined surface is flat and smooth. The cross-section profile of the microgroove machined by laser is M-shaped and there are obvious humps along the two sides of the microgroove. The microgroove bottom is almost at the same height with the unmachined surface. Besides, there are HAZs with a width of 50–100 µm and scaly recast layers on the sides of the cut machined by laser. In contrast, there is no recast layer and HAZ on the cut side of the hybrid laser-waterjet Micromachining. The texture of the cut sidewall is clear and with the typical features of the material removed under the plastic mode. The EDS results show that the oxidation behavior happens during both the hybrid laser-waterjet Micromachining and laser machining. However, the content of silicon dioxide generated in the hybrid laser-waterjet Micromachining process (the oxygen content is about 5%) is obviously lower than that generated in laser machining (the oxygen content is more than 30%).
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material removal of single crystal 4h sic wafers in hybrid laser waterjet Micromachining process
Materials Science in Semiconductor Processing, 2018Co-Authors: Shaochuan Feng, Chuanzhen Huang, Jun Wang, Hongtao ZhuAbstract:Abstract Yield stress, as well as ultimate stress, decreases with an increased temperature. A much smaller cutting force can be applied to perform the machining at high temperatures. Material is considered “softened” when its yield and ultimate stresses decrease due to the increase of temperature. During the hybrid laser-waterjet Micromachining process, the material is heated by laser. Once the critical resolved shear stress (CRSS), related to the yield stress, decreases to be equal to the applied resolved shear stress induced by the pressurized waterjet impingement, the material begins to be deformed and then removed plastically. The hybrid laser-waterjet Micromachining technology shows a satisfying performance on almost damage-free and high-efficient Micromachining of thermal-sensitive and hard-brittle materials at their “softened” status. The present study is focused on the material removal mechanism of single crystal 4H-SiC in the hybrid laser-waterjet Micromachining process. The temperature-dependent CRSS on the primary slip system of 4H-SiC is formulated. It is shown that the CRSS of 4H-SiC is less than 5 MPa at 1650 K. The shear stress induced by pressurized waterjet impingement, laser heating effect under the laser-water interference and the waterjet cooling effect are respectively studied. The range of water pressure used in the machining process is from 4 MPa to 13 MPa. A 2-D numerical model is developed using the finite difference method (FDM). The simulations show that the material begins to be removed before the laser intensity reaches its maximum in a laser pulse cycle. The depth and width of the microgroove increase gradually in the following several cycles. The increments become gradually less until this increase stops. The material is removed before it’s heated to its melting temperature and at a softened but still solid status. Heat accumulation between laser pulses is not expected in the process. The machined surface quality and material removal mechanisms of the hybrid laser-waterjet Micromachining and laser dry ablation are compared by 3D profiles and SEM photographs of the microgrooves obtained from these two machining methods. The surface quality obtained from hybrid laser-waterjet Micromachining is better than that obtained from laser dry ablation. The protrusion strips along the cut edges of laser dry ablation are scaly and similar to welded junction. It indicates that the material is melted or vaporized by laser heating and re-solidified at cut edges to form a recast layer during laser dry ablation. There aren’t recast layers on the machined surface of hybrid laser-waterjet Micromachining. Its surface texture is characterized as a typical feature of plastic slip.
Jun Wang - One of the best experts on this subject based on the ideXlab platform.
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surface quality evaluation of single crystal 4h sic wafer machined by hybrid laser waterjet comparing with laser machining
Materials Science in Semiconductor Processing, 2019Co-Authors: Shaochuan Feng, Chuanzhen Huang, Jun WangAbstract:Abstract Single crystal silicon carbide (SiC), as a 3rd generation semiconductor material, has a wide application range and development prospect, especially in some key fields such as defense and aerospace industries. It's a typical difficult-to-machine and hard-brittle material due to its high hardness and brittleness. A hybrid laser-waterjet Micromachining technology was employed to implement near damage-free and high-efficient Micromachining of single crystal SiC. The workpiece material is heated by laser to a temperature near but below its melting point. The material is under an extremely “softened” but still solid status. A waterjet is applied off-axially to expel the heating-softened material and cool the material to eliminate thermal damage. It combines the advantages of laser processing with those of waterjet cutting. Moreover, it's a green machining approach, which is pollution-free and recyclable. In the present study, the surface quality of single crystal 4H-SiC machined by the hybrid laser-waterjet is evaluated and compared with that machined by laser. Among the wafers respectively machined by laser, under-water laser, waterjet-assisted laser and the hybrid laser-waterjet, the one machined by the hybrid laser-waterjet is with the best surface quality. Its cut boundaries between the machined area and the unmachined area are clear, the cut edges are straight, also the cut sides are clean. On the contrary, there is severe thermal damage along the cut edges and cut sides of laser machining. The microgrooves obtained from the hybrid laser-waterjet Micromachining are with V-shaped cross-sections and the transition between the cut edge and the unmachined surface is flat and smooth. The cross-section profile of the microgroove machined by laser is M-shaped and there are obvious humps along the two sides of the microgroove. The microgroove bottom is almost at the same height with the unmachined surface. Besides, there are HAZs with a width of 50–100 µm and scaly recast layers on the sides of the cut machined by laser. In contrast, there is no recast layer and HAZ on the cut side of the hybrid laser-waterjet Micromachining. The texture of the cut sidewall is clear and with the typical features of the material removed under the plastic mode. The EDS results show that the oxidation behavior happens during both the hybrid laser-waterjet Micromachining and laser machining. However, the content of silicon dioxide generated in the hybrid laser-waterjet Micromachining process (the oxygen content is about 5%) is obviously lower than that generated in laser machining (the oxygen content is more than 30%).
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material removal of single crystal 4h sic wafers in hybrid laser waterjet Micromachining process
Materials Science in Semiconductor Processing, 2018Co-Authors: Shaochuan Feng, Chuanzhen Huang, Jun Wang, Hongtao ZhuAbstract:Abstract Yield stress, as well as ultimate stress, decreases with an increased temperature. A much smaller cutting force can be applied to perform the machining at high temperatures. Material is considered “softened” when its yield and ultimate stresses decrease due to the increase of temperature. During the hybrid laser-waterjet Micromachining process, the material is heated by laser. Once the critical resolved shear stress (CRSS), related to the yield stress, decreases to be equal to the applied resolved shear stress induced by the pressurized waterjet impingement, the material begins to be deformed and then removed plastically. The hybrid laser-waterjet Micromachining technology shows a satisfying performance on almost damage-free and high-efficient Micromachining of thermal-sensitive and hard-brittle materials at their “softened” status. The present study is focused on the material removal mechanism of single crystal 4H-SiC in the hybrid laser-waterjet Micromachining process. The temperature-dependent CRSS on the primary slip system of 4H-SiC is formulated. It is shown that the CRSS of 4H-SiC is less than 5 MPa at 1650 K. The shear stress induced by pressurized waterjet impingement, laser heating effect under the laser-water interference and the waterjet cooling effect are respectively studied. The range of water pressure used in the machining process is from 4 MPa to 13 MPa. A 2-D numerical model is developed using the finite difference method (FDM). The simulations show that the material begins to be removed before the laser intensity reaches its maximum in a laser pulse cycle. The depth and width of the microgroove increase gradually in the following several cycles. The increments become gradually less until this increase stops. The material is removed before it’s heated to its melting temperature and at a softened but still solid status. Heat accumulation between laser pulses is not expected in the process. The machined surface quality and material removal mechanisms of the hybrid laser-waterjet Micromachining and laser dry ablation are compared by 3D profiles and SEM photographs of the microgrooves obtained from these two machining methods. The surface quality obtained from hybrid laser-waterjet Micromachining is better than that obtained from laser dry ablation. The protrusion strips along the cut edges of laser dry ablation are scaly and similar to welded junction. It indicates that the material is melted or vaporized by laser heating and re-solidified at cut edges to form a recast layer during laser dry ablation. There aren’t recast layers on the machined surface of hybrid laser-waterjet Micromachining. Its surface texture is characterized as a typical feature of plastic slip.
B. Bhattacharyya - One of the best experts on this subject based on the ideXlab platform.
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influence of electrochemical Micromachining process parameters during fabrication of varactor micropattern
The International Journal of Advanced Manufacturing Technology, 2018Co-Authors: S Kunar, Subrata Mahata, B. BhattacharyyaAbstract:A simple method is demonstrated for the generation of micropattern of varactor by electrochemical Micromachining (EMM), which is considered as the most effective advanced Micromachining technique due to numerous advantages and wide range of applications. The generated micropatterns of varactor are used in many applications, i.e., radio frequency (RF) circuits including voltage-controlled oscillators and filters, parametric amplifiers, etc. Varactor is used as a variable capacitor which is used mainly for tuning the circuit by impedance matching. Usually, they are made of semiconductors and these cause losses in high-frequency communication. On the other hand, MEMS metal varactors tune their capacitance by adjusting the device’s physical parameters like dimensions, tuning area, and sometimes dielectric material via electromechanical actuation. The fabricated metal varactors enhance the tuning range of the varactor and reduce the losses. The varactor impression can be transferred on stainless steel surfaces by electrochemical Micromachining. EMM set-up has been developed fruitfully to control the influence of electrochemical Micromachining (EMM) parameters to obtain the controlled micro-features of varactor. The single patterned varactor tool is used for the mass production of varactors and avoids the need of masks on individual workpieces. The texturing time is short enough for application in an industrial context. One mathematical model is developed for the determination of theoretical depth of micropatterned surface and correlates with experimental results. The process has been characterized in terms of the effects of predominant process parameters such as machining voltage, duty ratio, pulse frequency, inter-electrode gap, and flow velocity on performance characteristics, i.e., material removal rate (MRR) and machining depth.
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investigation into electrochemical Micromachining process during micro channel generation
Materials and Manufacturing Processes, 2011Co-Authors: M Malapati, B. BhattacharyyaAbstract:Electrochemical Micromachining (EMM) appears to be very promising as a future Micromachining process due to higher machining rate, better precision and control, and wide range of materials that can be machined. The present article highlights the experimental study of EMM process parameters, i.e., pulse frequency, machining voltage, duty ratio, electrolyte concentration, and micro-tool feed-rate, and their influences on Micromachining criteria such as material removal rate (MRR) and machining accuracy during micro-channel generation. Scanning type strategy is considered for the movement of micro-tool during micro-channel generation Experiments are planned based on response surface methodology (RSM) and conducted on the indigenously developed EMM system setup. Empirical mathematical models of various process parameters on MRR and machining accuracy in EMM process are developed through RSM. The validity of the models is tested through analysis of variance (ANOVA). Optimal values for multiobjective optimizati...
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investigation into electrochemical Micromachining emm through response surface methodology based approach
The International Journal of Advanced Manufacturing Technology, 2008Co-Authors: Josiah Munda, B. BhattacharyyaAbstract:Electrochemical Micromachining (EMM) could be used as one the best Micromachining technique for machining electrically conducting, tough and difficult to machine material with appropriate machining parameters combination. This paper attempts to establish a comprehensive mathematical model for correlating the interactive and higher-order influences of various machining parameters, i.e. machining voltage pulse on/off ratio, machining voltage, electrolyte concentration, voltage frequency and tool vibration frequency on the predominant Micromachining criteria, i.e. the material removal rate and the radial overcut through response surface methodology (RSM), utilizing relevant experimental data as obtained through experimentation. Validity and correctiveness of the developed mathematical models have also been tested through analysis of variance. Optimal combination of these predominant Micromachining process parameters is obtained from these mathematical models for higher machining rate with acuuracy. Considering MRR and ROC simultaneously optimum values of predominant process parameters have been obtained as; pulse on/off ratio, 1.0, machining voltage, 3 V, electrolyte concentration, 15 g/l, voltage frequency of 42.118 Hz and tool vibration frequency as 300 Hz. The effects of various process parameters on the machining rate and radial overcut are also highlighted through different response surface graphs. Condition of machined micro-holes are also exhibited through the SEM micrographs in this paper. Pulse voltage pattern during electrochemical Micromachining process has been analyzed with the help of voltage graphs. Irregularities in the nature of pulse voltage pattern during electrochemical Micromachining have been observed and the causes of these irregularities are further investigated.
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Experimental investigation on the influence of electrochemical machining parameters on machining rate and accuracy in Micromachining domain
International Journal of Machine Tools & Manufacture, 2003Co-Authors: B. Bhattacharyya, Josiah MundaAbstract:Abstract Non-conventional machining is increasing in importance due to some of the specific advantages which can be exploited during Micromachining operation. Electrochemical Micromachining (EMM) appears to be a promising technique, since in many areas of application, it offers several special advantages that include higher machining rate, better precision and control, and a wider range of materials that can be machined. A better understanding of high rate anodic dissolution is urgently required for EMM to become a widely employed manufacturing process in the micro-manufacturing domain. An attempt has been made to develop an EMM experimental set-up for carrying out in depth research for achieving a satisfactory control of the EMM process parameters to meet the Micromachining requirements. Keeping in view these requirements, sets of experiments have been carried out to investigate the influence of some of the predominant electrochemical process parameters such as machining voltage, electrolyte concentration, pulse on time and frequency of pulsed power supply on the material removal rate (MRR) and accuracy to fulfil the effective utilization of electrochemical machining system for Micromachining. A machining voltage range of 6 to 10 V gives an appreciable amount of MRR at moderate accuracy. According to the present investigation, the most effective zone of pulse on time and electrolyte concentration can be considered as 10–15 ms and 15–20 g/l, respectively, which gives an appreciable amount of MRR as well as lesser overcut. From the SEM micrographs of the machined jobs, it may be observed that a lower value of electrolyte concentration with higher machining voltage and moderate value of pulse on time will produce a more accurate shape with less overcut at moderate MRR. Micro-sparks occurring during Micromachining operation causes uncontrolled material removal which results in improper shape and low accuracy. The present experimental investigation and analysis fulfils various requirements of Micromachining and the effective utilization of ECM in the Micromachining domain will be further strengthened.
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experimental investigation into electrochemical Micromachining emm process
Journal of Materials Processing Technology, 2003Co-Authors: B. Bhattacharyya, Josiah MundaAbstract:Abstract Due to several advantages and wider range of applications, electrochemical Micromachining (EMM) is considered to be one of the most effective advanced future Micromachining techniques. A suitable EMM setup mainly consists of various components and sub-systems, e.g. mechanical machining unit, micro-tooling system, electrical power and controlling system and controlled electrolyte flow system etc. have been developed successfully to control electrochemical machining (ECM) parameters to meet the Micromachining requirements. Investigation indicates most effective zone of predominant process parameters such as machining voltage and electrolyte concentration, which give the appreciable amount of material removal rate (MRR) with less overcut. The experimental results and analysis on EMM will open up more application possibilities for EMM.
Josiah Munda - One of the best experts on this subject based on the ideXlab platform.
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investigation into electrochemical Micromachining emm through response surface methodology based approach
The International Journal of Advanced Manufacturing Technology, 2008Co-Authors: Josiah Munda, B. BhattacharyyaAbstract:Electrochemical Micromachining (EMM) could be used as one the best Micromachining technique for machining electrically conducting, tough and difficult to machine material with appropriate machining parameters combination. This paper attempts to establish a comprehensive mathematical model for correlating the interactive and higher-order influences of various machining parameters, i.e. machining voltage pulse on/off ratio, machining voltage, electrolyte concentration, voltage frequency and tool vibration frequency on the predominant Micromachining criteria, i.e. the material removal rate and the radial overcut through response surface methodology (RSM), utilizing relevant experimental data as obtained through experimentation. Validity and correctiveness of the developed mathematical models have also been tested through analysis of variance. Optimal combination of these predominant Micromachining process parameters is obtained from these mathematical models for higher machining rate with acuuracy. Considering MRR and ROC simultaneously optimum values of predominant process parameters have been obtained as; pulse on/off ratio, 1.0, machining voltage, 3 V, electrolyte concentration, 15 g/l, voltage frequency of 42.118 Hz and tool vibration frequency as 300 Hz. The effects of various process parameters on the machining rate and radial overcut are also highlighted through different response surface graphs. Condition of machined micro-holes are also exhibited through the SEM micrographs in this paper. Pulse voltage pattern during electrochemical Micromachining process has been analyzed with the help of voltage graphs. Irregularities in the nature of pulse voltage pattern during electrochemical Micromachining have been observed and the causes of these irregularities are further investigated.
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Experimental investigation on the influence of electrochemical machining parameters on machining rate and accuracy in Micromachining domain
International Journal of Machine Tools & Manufacture, 2003Co-Authors: B. Bhattacharyya, Josiah MundaAbstract:Abstract Non-conventional machining is increasing in importance due to some of the specific advantages which can be exploited during Micromachining operation. Electrochemical Micromachining (EMM) appears to be a promising technique, since in many areas of application, it offers several special advantages that include higher machining rate, better precision and control, and a wider range of materials that can be machined. A better understanding of high rate anodic dissolution is urgently required for EMM to become a widely employed manufacturing process in the micro-manufacturing domain. An attempt has been made to develop an EMM experimental set-up for carrying out in depth research for achieving a satisfactory control of the EMM process parameters to meet the Micromachining requirements. Keeping in view these requirements, sets of experiments have been carried out to investigate the influence of some of the predominant electrochemical process parameters such as machining voltage, electrolyte concentration, pulse on time and frequency of pulsed power supply on the material removal rate (MRR) and accuracy to fulfil the effective utilization of electrochemical machining system for Micromachining. A machining voltage range of 6 to 10 V gives an appreciable amount of MRR at moderate accuracy. According to the present investigation, the most effective zone of pulse on time and electrolyte concentration can be considered as 10–15 ms and 15–20 g/l, respectively, which gives an appreciable amount of MRR as well as lesser overcut. From the SEM micrographs of the machined jobs, it may be observed that a lower value of electrolyte concentration with higher machining voltage and moderate value of pulse on time will produce a more accurate shape with less overcut at moderate MRR. Micro-sparks occurring during Micromachining operation causes uncontrolled material removal which results in improper shape and low accuracy. The present experimental investigation and analysis fulfils various requirements of Micromachining and the effective utilization of ECM in the Micromachining domain will be further strengthened.
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experimental investigation into electrochemical Micromachining emm process
Journal of Materials Processing Technology, 2003Co-Authors: B. Bhattacharyya, Josiah MundaAbstract:Abstract Due to several advantages and wider range of applications, electrochemical Micromachining (EMM) is considered to be one of the most effective advanced future Micromachining techniques. A suitable EMM setup mainly consists of various components and sub-systems, e.g. mechanical machining unit, micro-tooling system, electrical power and controlling system and controlled electrolyte flow system etc. have been developed successfully to control electrochemical machining (ECM) parameters to meet the Micromachining requirements. Investigation indicates most effective zone of predominant process parameters such as machining voltage and electrolyte concentration, which give the appreciable amount of material removal rate (MRR) with less overcut. The experimental results and analysis on EMM will open up more application possibilities for EMM.
Chuanzhen Huang - One of the best experts on this subject based on the ideXlab platform.
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surface quality evaluation of single crystal 4h sic wafer machined by hybrid laser waterjet comparing with laser machining
Materials Science in Semiconductor Processing, 2019Co-Authors: Shaochuan Feng, Chuanzhen Huang, Jun WangAbstract:Abstract Single crystal silicon carbide (SiC), as a 3rd generation semiconductor material, has a wide application range and development prospect, especially in some key fields such as defense and aerospace industries. It's a typical difficult-to-machine and hard-brittle material due to its high hardness and brittleness. A hybrid laser-waterjet Micromachining technology was employed to implement near damage-free and high-efficient Micromachining of single crystal SiC. The workpiece material is heated by laser to a temperature near but below its melting point. The material is under an extremely “softened” but still solid status. A waterjet is applied off-axially to expel the heating-softened material and cool the material to eliminate thermal damage. It combines the advantages of laser processing with those of waterjet cutting. Moreover, it's a green machining approach, which is pollution-free and recyclable. In the present study, the surface quality of single crystal 4H-SiC machined by the hybrid laser-waterjet is evaluated and compared with that machined by laser. Among the wafers respectively machined by laser, under-water laser, waterjet-assisted laser and the hybrid laser-waterjet, the one machined by the hybrid laser-waterjet is with the best surface quality. Its cut boundaries between the machined area and the unmachined area are clear, the cut edges are straight, also the cut sides are clean. On the contrary, there is severe thermal damage along the cut edges and cut sides of laser machining. The microgrooves obtained from the hybrid laser-waterjet Micromachining are with V-shaped cross-sections and the transition between the cut edge and the unmachined surface is flat and smooth. The cross-section profile of the microgroove machined by laser is M-shaped and there are obvious humps along the two sides of the microgroove. The microgroove bottom is almost at the same height with the unmachined surface. Besides, there are HAZs with a width of 50–100 µm and scaly recast layers on the sides of the cut machined by laser. In contrast, there is no recast layer and HAZ on the cut side of the hybrid laser-waterjet Micromachining. The texture of the cut sidewall is clear and with the typical features of the material removed under the plastic mode. The EDS results show that the oxidation behavior happens during both the hybrid laser-waterjet Micromachining and laser machining. However, the content of silicon dioxide generated in the hybrid laser-waterjet Micromachining process (the oxygen content is about 5%) is obviously lower than that generated in laser machining (the oxygen content is more than 30%).
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material removal of single crystal 4h sic wafers in hybrid laser waterjet Micromachining process
Materials Science in Semiconductor Processing, 2018Co-Authors: Shaochuan Feng, Chuanzhen Huang, Jun Wang, Hongtao ZhuAbstract:Abstract Yield stress, as well as ultimate stress, decreases with an increased temperature. A much smaller cutting force can be applied to perform the machining at high temperatures. Material is considered “softened” when its yield and ultimate stresses decrease due to the increase of temperature. During the hybrid laser-waterjet Micromachining process, the material is heated by laser. Once the critical resolved shear stress (CRSS), related to the yield stress, decreases to be equal to the applied resolved shear stress induced by the pressurized waterjet impingement, the material begins to be deformed and then removed plastically. The hybrid laser-waterjet Micromachining technology shows a satisfying performance on almost damage-free and high-efficient Micromachining of thermal-sensitive and hard-brittle materials at their “softened” status. The present study is focused on the material removal mechanism of single crystal 4H-SiC in the hybrid laser-waterjet Micromachining process. The temperature-dependent CRSS on the primary slip system of 4H-SiC is formulated. It is shown that the CRSS of 4H-SiC is less than 5 MPa at 1650 K. The shear stress induced by pressurized waterjet impingement, laser heating effect under the laser-water interference and the waterjet cooling effect are respectively studied. The range of water pressure used in the machining process is from 4 MPa to 13 MPa. A 2-D numerical model is developed using the finite difference method (FDM). The simulations show that the material begins to be removed before the laser intensity reaches its maximum in a laser pulse cycle. The depth and width of the microgroove increase gradually in the following several cycles. The increments become gradually less until this increase stops. The material is removed before it’s heated to its melting temperature and at a softened but still solid status. Heat accumulation between laser pulses is not expected in the process. The machined surface quality and material removal mechanisms of the hybrid laser-waterjet Micromachining and laser dry ablation are compared by 3D profiles and SEM photographs of the microgrooves obtained from these two machining methods. The surface quality obtained from hybrid laser-waterjet Micromachining is better than that obtained from laser dry ablation. The protrusion strips along the cut edges of laser dry ablation are scaly and similar to welded junction. It indicates that the material is melted or vaporized by laser heating and re-solidified at cut edges to form a recast layer during laser dry ablation. There aren’t recast layers on the machined surface of hybrid laser-waterjet Micromachining. Its surface texture is characterized as a typical feature of plastic slip.
