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Process researching on high resolution and high ratio of depth to width of the negative photoresist (SU-8) process on micro-structure, by means of orthogonal experimental,drawing that the soft baking temperature and soft baking time have the greatest impact on the quality of the lithography. When the thick of photoresist is between 120μm with 340μm, the soft baking temperature is 90°C and the soft baking time is between 50min with 120min, the graphics quality is best. Then, analysis of characteristics of the ratio of high to depth on micro-structure electroforming shows that the mass transfer is the restrictive link of micro electroforming. Which can achieve the process parameters optimization of the lithography and electroforming micro-structure.

In recent years, micro-machining has obtained increasingly attention and been more and more widely used in the field of machining. As a vital important aspect in the design of micro-tool, traditional tool geometry design methods need to be improved. In this paper, the mathematical model of D-type micro end-mill is developed; FEM analysis using ABAQUS 6.12 is employed to optimize the geometry parameters of D-type micro end-mill, which is proved to be a very convenient method. For small diameter tools, strength is the primary factor to be considered in their design, so the target of optimization is to minimize the maximum principal stress and deformation of the micro-tools.

The relationship between the composition, coating microstructure and electromagnetic properties of electroforming Ni-Fe alloys was studied in this paper. And the optimal process parameters to obtain Ni-20%Fe deposition was as following: FeSO4•7H20 concentration was 6 g/L; PH value of the solution was 2.5; current density was 3.5 A/dm2; electrolyte temperature 55 °C. The results indicate that the Ni-Fe deposit is bright and compact, the crystal-planes of the plating were (111), (220) and (200). Electrodeposited Ni-20%Fe has a strong paramagnetism effect with the smallest remanence of 0.5 emu, The coercivity show a monotonic decrease with increasing Fe content in deposit, which proved that the electroformed Ni-20%Fe alloy has good electromagnetic property and could be used in MEMS actuator manufacturing.

The artificial neural network (ANN) and Orthogonal experimental design was applied in the research of main process parameters of electroforming Ni-Fe microstructure. In order to obtain the suitable parameters of the deposit, an ANN with 3 layers was built and trained based on orthogoality experiment using back propagation algorithm. The characteristics of the micro electroforming process were analysed systematically. And the optimal process parameters to obtain Ni-20% Fe deposition was as following: FeSO4•7H20 concentration: 5.5 g/L; PH value of the solution: 2.5; current density: 3.5 A/dm2; electrolyte temperature: 55 °C. The results indicate that the Ni-Fe deposit is bright and compact. Electrodeposited Ni-20% Fe has a strong paramagnetic effect with the smallest value of remanence 0.036 mA•m2 and the coercivity: 0.187 kA/m. The Ni-Fe micro electroplating process for the fabrication of microstructure was optimised.

This paper investigated an novel wireless RF pressure sensor fabricated with SU-8 polymer. The sensor consists of an inductor (L) interconnected with pressure-variable capacitor (C) to form a LC resonant circuit. The fabricated devices is 4 × 3 mm2 in size and houses 9 turns of Cu electro-plated coil with inductance of 100 nH. In this system, RF signal was transmitted from external antenna to the fabricated LC resonator. Then RF signal was changed as power of fabricated device via inductive coupling. The external antenna was modulated by resonant frequency of the LC resonator. By detecting this abrupt resonant frequency shift of the device, the pressure change of the device can be measured by wireless method.

Using functions of the parametric design and assembling in Pro/E, the parametric model for parts of shaping machine was established and the virtual assembly of shaping machine was achieved according to the parts of the assembly relationship in Pro/E assembly environment. Using functions of gap analysis and interference check in Pro/E,it can check interference to find and amend parts structure of shaping machine and can analyse gap to find the assembly relationship of shaping machine. Through the motion simulation, it can simulate movement of various parts of shaping machine in virtual environment. Using the method of virtual assembly ,it can met the design requirement of shaping machine, reduce the design cost of shaping machine, shorten the product development cycle, improve the design efficiency. It has offered a kind of new design method and implementation way for research of the model.

Microburrs have great influence on printed circuit board’s quality. PCB is composed of glass fiber plastic reinforcement material and copper foil. The PCB microburrs are generated in copper foil drilling process. These burrs are generated by copper extrusion and accumulation around the micro-hole. Enter burr and exit burr is quite different. Enter burrs are lower than exit burrs. The burr formation experienced three stages: First, Copper foil extrudes with the feed of microdrill; Second, Most of the Materials are cut off by drill tip and the rest of material; At last, rollover burrs appear when drill enters or exits uncut chip rolls.

High cutting force, high cutting temperature and severe adhesion will be produced in the machining process of Ti-6Al-1.5Cr-2.5Mo-0.5Fe-0.3Si. Furthermore, there are critical needs to reduce the use of cutting fluid in machining process. This paper presents a friction force model under MQL condition. An experiment of turning titanium alloy was presented to test and analyze MQL effects. The mainly results were: (1) MQL can reduce the friction at the chip-tool interface when cutting parameters and matching parameters of MQL were chosen properly. (2) Degrees of serrated chips and chip morphology affected by different lubrication conditions were different.

Tool breakage monitoring is crucial to automation fabrication, especially for high-density hole machining, such as PCB (Printed Circuit Board). A tool breakage feature extraction method in PCB micro-hole drilling is presented in this paper. The vibration signal is analyzed by wavelet transform. The decomposed signals energy ratio at each frequency band is computed as monitoring features. The monitoring performance of different features selection is given. The vibration signals are observed to provide the capability in distinguishing micro drill breakage with proper features extraction and classifier design.

Printed circuit board (PCB) composed of glass fiber reinforcement plastic and copper foil is a kind of typical composite material. The cutting process of fiber reinforcement plastic materials such as carbon fiber or glass fiber reinforcement plastic materials have been studied for many years, but the drilling process of printed circuit board using microdrill is more complicated than common carbon fiber reinforcement plastic materials. It is event that the cutting force changed when drill different material. The variation of drilling force may cause some problems such as drill break, board delamination. So it is important to study the drilling force in PCB drilling. The precision dy-namometer was used in experiments and cutting process was analyzed in this paper. The drilling process of PCB experience six stages and the drill will meet aluminum board, glass fiber reinforce-ment plastic (GFRP) and base strip. According to the drilling force in one circle, the peak force ap-peared at the moment of drilling copper foil and another smaller peak force appeared at the moment of drilling aluminum board and base board. The experiment results show that thrust force increased with federate and decreased with rotational speed.

More and more attention is put on the machinability of printed circuit board (PCB) with the increasing demand of PCBs driven by the strong need of the market of the electronic products. In this paper, drill wear and burr size, as two main objects of experimental investigation, have been observed and analyzed in drilling PCB through-holes. The results of the drilling experiment conducted with normal drill and specialized drill, indicate that appropriate chisel edge thinning is in favor of decreasing flank wear of the drill, but has no apparent effect on reducing burr size for PCB through-holes drilling.

In recent years, with the development of machinery industry, micro-cutting technologies have been gradually moving into engineering realization. The paper carries out a series of works on simulation modeling of micro-cutting of Ti-5Al-5V-5Mo-3Cr considering tool edge radius. Unlike conventional cutting, in micro-cutting the effect of tool edge radius which has a marked impact on cutting force, specific cutting energy, burr formation and burr size can no longer be neglected.

Titanium alloy is widely used in aerospace and aircraft industries but it is a kind of difficult-to-cut material. In this paper, wet grinding and dry grinding of titanium alloy Ti-6Al-4V using green silicon carbide wheel were investigated. The specific tangential force and force ratio were calculated and surface roughness of machined surfaces was measured. The morphology of machined surface were observed by SEM. The experimental results showed that the specific tangential forces were big. The depth of cutting has greater influence on surface roughness than workpiece speed. The surface roughness of wet grinding was better than dry grinding. Micro cracks were observed on wet grinding. The main reason is the high temperature and quenching cracking.

Experimental results of Ti-6-2-4-2S, Ti-6-4 and Ti-5-5-5-1-1 are detailed in this paper with conventional surface grinding using SiC abrasive under dry conditions. Measurements of grinding forces, surface topography and metallurgical structure of ground surface were taken to investigate the grinding mechanism of these materials. The results showed grinding force ratios to these materials were between 1.35 to 2.25 at all material remove rates, but the specific energy to Ti-5-5-5-1-1 and Ti-6-2-4-2S were little higher than Ti-6-4. Evaluation of ground surface topography indicated they were visually free of crack and burn. At the same grinding parameters, Ti-5-5-5-1-1 had the maximum depth of heat-affected zone because of its poor high temperature properties.

This paper investigates the surface grinding of Ti-6Al-4V under minimum quantity lubrication (MQL) condition. The experiment result indicated that grinding force ratio and specific energy have close related to grinding parameters. Due to the flow field of MQL mist has easy been affected by feed rate, the interaction between of MQL mist flow field and feed rates of worktable has great effect on surface roughness and surface quality. Additionally, comparing to dry grinding, MQL could help to improve surface quality by restrain chemical reactions and physical changes.

This paper presented a method of FEM simulation in thread milling machining for designing PCD milling tool. Thread milling technology is a new method to replace common tapping process. PCD tool is proper for high efficiency aluminum machining. The proper geometries of PCD thread milling tool are gained by FEM method and the cutting test proved that PCD tool can instead the carbide thread tool and do better performance than that.

A new grinding method for PCB drill-helical-conical grinding method which is combined helical method and conical method is introduced in this paper. Compared with conical grinding method, helical-conical grinding method avoids the tail rising problem and improves the clearance angle distribution along with the main cutting edge. The mathematical model of this method is given in this paper.

A micro grooved finger has smaller bending stiffness and can be used to improve the performance of some micro cantilever devices. The deflection and bending stiffness of a micro grooved finger are discussed in this paper. An analytical model of the deflection is built up to study the effect of the groove sizes on the bending stiffness and the deflection of the grooved finger. The calculation of the analytical model is consistent with the simulation and experiment results. When the grooves depth is 0.5 μm, the spring constant of grooved micro finger is 19.8% smaller than that of flat finger without groove patterns. The spring constant of the finger decreases with the increasing of the width and depth of the groove. A novel micro electric-thermal gripper is introduced based on the grooved finger. It consists of four sub-cantilever beams arranged at the diagonal lines of the square frame in the end of the main cantilever structure suspended from the silicon substrate, which guarantees an effective contact by the four-point contact area on the top surface to grab object of importance. The thermal expansion induced deflection makes the fingers moving vertically from an ‘open’ position to a working one. The grooved fingers help to decrease the bending stiffness of the finger and increase the deflection and the initial gap. The simple fabrication process has a feasibility of compatible and mass production.

An analytical model of an eddy current sensor designed for noncontact distance measurement is presented. The device consists of two planar coil (driver coil and pickup coil) stacked on the magnetic core. The planar coil fabricated by UV-LIGA technology with SU-8 photoresist is illustrated, and the permalloy magnetic core electroforming process is presented also. Tested with 10-50 KHz sine signal, the output voltage of the sensing coil reached 30mv with a Ni target placed at a distance of 20μm. And the experimental showed a linear relation between the distance and output voltage within 60μm distance. The amplitude trend increases with the increasing of the frequency and amplitude of excited signal, which is according with the theory analytics. The whole size of the device is: Φ5mm×1.5mm. The results demonstrated that the device could nondestructive evaluate the distance and be easily integrated on chip, and the UV-LIGA Process could be used as a new method to fabricate the micro eddy current sensor massly.

The petroleum pipes are key component of petroleum drilling instrument. Residual stress distribution and work hardening in oil pipe turning are discussed through cutting experiment. The experiment result shows that the depth of residual stress affecting layer is small but residual stress is big while work hardening is severe. The prediction of residual stress, cutting force and temperature are achieved through FEM method. The simulation results are constant with experiment results.

13%Cr stainless steel has good comprehensive performance, which makes it suitable to work under the condition of high temperature, high pressure and corrosive environment, such as petroleum industry. It can be used as materials of petroleum pipes with buttress thread. Buttress thread turning is a heavy-load machining, which places high requirement on the cutting tool. Based on the cutting characteristics of buttress thread, the machinability of 13%Cr stainless steel is studied by turning experiments. Two kinds of inserts with different geometries were employed in buttress thread turning experiments. Experimental results show that less cutting force, longer tool life, better chip curling effect and surface quality was acquired for the insert with rake angle of 12° , clearance angle of 3° and chip-curling groove during 13%Cr stainless steel buttress thread turning process.

A new special drill is developed for iron cast drilling. The special drill has double point angle and 0°chisel rake angle which can decrease cutting force, tool wear and cutting temperature. Drilling performance is evaluated by trust force, torque, tool wear. The results indicate that new special drill is suitable for iron cast drilling with small cutting force and long tool life.

An improved architecture, which performs a universal set of gates by current biasing of coupling Josephson junction, has been proposed. This improvement is necessary to the realization of a functional and scalable quantum computer. The proposed architecture is in line with current technology. Secondly, we investigate a scheme for implementing the Deutsch–Jozsa algorithm via the improved architecture. It is a simple, scalable and feasible scheme for the implementation of the Deutsch–Jozsa algorithm based on the current-controlled superconducting charge qubit network.

A physical scheme for implementing the one-qubit Deutsch–Jozsa algorithm by electronic population adiabatic transfer in a triple-well quantum dot system is proposed. The scheme is relatively insensitive to gate errors and other external noise. Furthermore, the implementation of Deutsch–Jozsa algorithm via the quantum dot system provides a good example for oracle-based solid quantum computing.

Based on the architecture of a superconducting charge qubit in [J. Lantz, M. Wallquist, V.S. Shumeiko, G. Wendin, Phys. Rev. B 70 (2004) 140507(R); M. Wallquist, J. Lantz, V.S. Shumeiko, G. Wendin, New J. Phys. 7 (2005) 178], we propose an improved architecture, which can provide a long-range interaction instead of the controllable nearest-neighbor coupling. It can provide two-qubit operation between arbitrary pairs of qubits, which is necessary for the realization of the functional and scalable quantum computing. We further investigate a scheme for generating multi-qubit cluster states which meets the expectations of the so-called one-way quantum computation schemes. It is a simple, scalable and feasible scheme for the generation of cluster states based on the current experiments about the controlled superconducting charge qubit network.

We propose an improved architecture for the physical implementation of two-qubit operations between arbitrary pairs of qubits by current biasing of coupled Josephson junctions. This improvement is necessary for the realization of a functional and scalable quantum computer. The proposed architecture is within the reach of current experimental technology. Secondly, we investigate a simple scheme for generating the graph states via the improved architecture. Since the controlled-phase gate between arbitrary pairs of qubits can be implemented easily, we can generate any multi-qubit graph states corresponding to various shape graphs, which meet the expectations of various quantum information processing schemes. It is a simple, scalable and feasible scheme for the generation of various graph states based on the current-controlled superconducting charge qubit network.

On the basis of generations of 1-dimensional and 2-dimensional graph states, we generate a 3-dimensional N3-qubit graph state based on the Josephson charge qubits. Since any two charge qubits can be selectively and effectively coupled by a common inductance, the controlled phase transform between any two-qubit can be performed. Accordingly, we can generate arbitrary multi-qubit graph states corresponding to arbitrary shape graph, which meet the expectations of various quantum information processing schemes. All the devices in the scheme are well within the current technology. It is a simple, scalable and feasible scheme for the generation of various graph states based on the Josephson charge qubits.

An analytical model of an eddy current sensor designed for noncontact distance measurement was presented. The device consists of two planar coil (driver coil and pickup coil) stacked on the magnetic core. The planar coil fabricated by UV-LIGA technology with SU8 photoresist was illustrated, and the permalloy magnetic core electroforming process was presented also. Tested with 10–50KHz sine signal, the output voltage on the sensing coil rearched 30mv with an stainless target placed at a distance of 10μm, and the experimental showed a linear relation between the distance and output voltage within 50μm distance. The whole size of the device was: Φ5mm × 1.5 mm. The results demonstrated that the device could nondestructive evaluate the distance and be easily integrated on chip.Copyright © 2007 by ASME

This paper was focused on the composition controlling, coating microstructure and electromagnetic character of Ni-Fe deposit. The results indicated that the Ni-Fe deposit was bright and compact; the crystal-planes of the deposit were (111), (220) and (200). And the optimal process parameters to obtain Ni-20%Fe deposition was as following: FeSO4·7H20 concentration was 6g/L; PH value of the solution was 2.5; current density was 3.5 A/dm2; electrolyte temperature 55°C. The resistivity of deposit was about 30μΩ·cm, when the Fe(wt.%) ranged from 10% to 50% in the deposit. Electrodeposited Ni-20%Fe has a strong paramagnetism effect with the smallest remanence of 0.5 emu, The coercivity show a monotonic decrease with increasing Fe content in deposit, and the saturation magnetization was only 10% of that of the IJ85 permalloy, which proved that the electroformed Ni-20%Fe alloy has good electromagnetic property and could be used in MEMS actuator fabrication.Copyright © 2007 by ASME

A scheme for the generation of the cluster states based on the Josephson charge qubit is proposed. The two-qubit generating case is first introduced, and then generalized to multi-qubit case. The scheme is simple and easily manipulated, because any two charge qubits can be selectively and effectively coupled by a common inductance. More manipulations can be realized before decoherence sets in. All the devices in the scheme are well within the current technology., Comment: 3 figures, 4 pages

This paper investigates the effects of minimum quantity lubrication (MQL) on the grinding performance of Ti-6Al-4V using SiC abrasive, the evaluation of the performance consists of analysing the grinding force, specific grinding energy, force ratio, surface roughness and surface morphology. The experiment results indicated that the favourable lubricating effect of MQL oil made it have the lowest value of grinding force, specific energy and force ratio. MQL had better surface finish than dry grinding, but fluid grinding had the lowest value of surface roughness under different grinding depth and worktable feed rate. Surface damages such as side flow, plastic deformation and redeposition were present in dry and fluid grinding. As grinding depth increased, the damages became much more severe. But in condition of MQL, it gave better surface integrity than dry and fluid grinding.