Abstract: This paper describes a new efficient internal finishing process for a thick tubing
(10~30mm in thickness), by the application of a magnetic field-assisted machining process using a
magnet tool. Because a stronger magnetic force can be generated than conventional magnetic
abrasives, it makes the internal finishing of thick non-ferromagnetic tubing possible. Moreover, in
order to obtain a high-quality surface, this process method was developed using magnetic particles
magnetically attracted on the magnet surface. This paper characterizes the processing principle and
advantages of this process. Then, the mechanism of this finishing process was examined by a plane
model experiment. It was clarified that the magnetism and shape of a magnetic particle influence
realization possibility of this processing method, and it also influence the finishing characteristics.
Abstract: Aiming at the ultra-sophisticated combined working machine tool that was developed,
the motion style of the machine tool when abrasive machining a sort of inward-curving-parabolic
shape optical aspherical surface device is analysed, according to the equation of the machined part’s
surface, the relative movement locus between the cutter and the machined part can be established
while using a spherical grinding wheel as grinding cutter. The caliber of the paraboloid that to be
processed is analysed, and the grinding wheel's installation angle is chosen, as well as the cutting
speed of the cutting spot is analysed, the abrasive model in ideal condition is analysed, the basis is
based for error compensating.
Abstract: A series of experiments is carried out on the characteristics at the wedge bond interface.
Bond lift-off characteristics are studied by using Scanning Electron Microscope with EDS-test. The
characteristics of input impedance of PZT transducer are analyzed by the driving electric signal
measured by Oscilloscope. Results show that the pattern of partially bonded material at the interface
of ultrasonic wedge bonds exposed by peeling underdeveloped bonds simulates a torus with an
unbonded central region. For the same machine variables, the input impedance and transforming
power of the first wedge bond are greater than that of the second wedge bond. Some conclusions
drawn by analyzing the input impedance and the power of PZT consist with the results gotten by
testing microstructures at the interface.
Abstract: This paper analyzes the cause of overshoot and retarded response in controlling
piezoelectric ceramic motor with PMAC card in micro WEDM. The model of start-stop control is
presented, and the servo control card with start-stop control is also developed. The model reserved
the advantages of traditional PID control, and overcome the problems of overshoot and retarded
response. It has been verified by machining that system overshoot is less than 3 pulses and response
time is less than 1 second.
Abstract: Rapid reverse technology is one of the key technologies with which the enterprises
develop new product and occupy the market rapidly. How to realize the reverse measurement and
CAD geometry reconstruction rapidly and accurately is always the most important focus for the
researchers. Based on the laser scanning technology, the realization principle of the laser line
scanning measuring system is presented and the approaches to improve the precision are also
analysed in the paper. The self-adaptation adjustment of the probe position can move the light knife
image to the optimal imaging area of the CCD according to the calibration result, which will ensure
the measurement precision of the CCD image. With the inner velocity loop and outer position loop
feedback control, the simple axis position precision of the mechanical system can be controlled
within 5um. In order to pick up the points of the light knife centre rationally and exactly, the
reconstruction-disperse iteration algorithm is put forward. After processed by different iteration
times, the optimal points can be obtained. The reconstruction method of curve and surface based on
NURBS is also given. The paper presents the application and realization of the system at last, which
realizes the curve and surface measurement with high precision.
Abstract: A 775nm femtosecond laser is applied to single crystal silicon by direct-write processing
in air. A series of holes are drilled with 150fs duration pulses, various numbers of laser pulses and
laser fluences on silicon wafer. Different laser parameters and material properties influence the size
of fabricated holes. The diameter and depth of holes are gradually enlarged with the increase of
laser fluence and pulse number. The periodic ripple structure on silicon surface is found and
explained at the same time.
Abstract: Finite-element methods are used to study non-adhesive, frictionless rough contact of
elastic and plastic solids. Roughness on the contact surfaces is realized by self-affine fractal. True
contact area between spherical rough surfaces and flat rigid surfaces rises in power law as the
external normal load increases. The power exponent is sensitive to surface roughness as well as the
curvature of spherical geometry. Surface contact pressures are analyzed and compared for elastic
and plastic solids. The distribution of local contact pressure is significantly dependent on the
surface roughness and the yield stress of plastic solids.
Abstract: Surface roughness is an important quality characteristic in grinding. Measurement of
surface roughness by means of mechanical stylus is widely done in metrology. In this paper, a new
machine vision system has been utilized to quantify the surface roughness of machined surfaces
(ground and milled). Compared with other measurement methods, it is accurate, quick and credible.
This system is mounted on the grinding machine and automates the measurement process by using
computer control to automatically position the CCD and capture digital images of machined
surfaces between grinding cycles. It was proposed that the proportional formula was used in
calibrating this system, and calibration precision meets application requirement. Not only the
statistic character of gray image but also which of edge image were calculated out. These characters
include the mean value of pixels (Mean), standard deviation (σ), maximal value (Max) and minimal
value (Min), the number of pixels on the examine line(Count), etc. It was found out that the
standard deviation value σ of the gray image could express the surface roughness most. The
correlation between σ and Ra is established by interpolating σ value used Lagrange interpolation
law, and the σ value is converted into Ra value through the calculation procedure finally.
Abstract: Chemical mechanical polishing (CMP) has become the preferred technology to achieve
global planarization of wafer surfaces. Especially in oxide CMP, mechanical factors have a greater
effect on the removal rate than chemical factors. So, the effects of mechanical parameters in CMP
can be expressed as friction force and heat caused by friction. The friction force can be evaluated by
a CMP friction force monitoring system and process temperature can be obtained by an infrared
rays (IR) sensor. Furthermore, friction energy can be calculated from the friction force monitoring
system. In this paper, research on the correlation between frictional and thermal characteristics of
SiO2 slurry and CMP results was conducted. This data, which was obtained by using integrated
monitoring system for CMP, will lead to the efficient prediction of CMP results.
Abstract: Precision measuring techniques have been developed interdependently with the
techniques of design and manufacturing in the history. Computer aided inspection plays a very
important role in modern manufacturing industry. On account of the CMM (Coordinates
Measurement Machine) being applied widely and the precision model inspection concept coming
true, it is possible to implement the digital inspection of the spiral bevel gear on the CMM. In this
paper the framework of the spiral bevel gear digital inspection based on the integration of
CAD/CAM/CMM is put forward. The key techniques of the scheme are investigated, which consist
of exact modeling of spiral bevel gear based on manufacturing process, datum matching of CAD
model and CMM inspection, CMM Inspection path planning, reconstruction of the tooth surface
based on the CMM inspection results, Analysis of the deviation between the real gear tooth and
CAD model, adjusting strategy of machining parameters.