Abstract: In the paper, the Molecular Dynamics (MD) simulation model and the Finite Element
(FE) analysis model were combined together to study the mechanism of the Electrolytic In-process
Dressing (ELID) grinding. A 3-D MD simulation model for grinding monocrystalline silicon was
established to acquire grinding force and its change laws, and an interpolation multinomial of
grinding force was established on the basis of MD simulation result. A FE model for abrasives and
the passivation film was established to calculate displacement of abrasives in the passivation film.
The grinding force and abrasives displacement were iterated between MD simulation model and FE
analysis model to obtain the displacement variation of the abrasives in the passivation film. The
simulation result shows that, the uniform height of the abrasives in the contour of the grinding
wheel is improved owing to the existence of passivation film in ELID grinding, it is related to the
thickness of the passivation film, and processing quality in ELID grinding could be enhanced
through controlling of thickness of the passivation film.
Abstract: Electrolytic In-process Dressing (ELID) has been applied in high speed grinding of
partially stabilized zirconia. Using a developed electrode system, the ELID effect on a bronze bond
diamond wheel was significant. This resulted in a decrease in grinding force, and thus improved the
ground surface quality. The improvement of grinding performance was attributed to the good
maintenance of wheel sharpness by ELID dressing.
Abstract: The physics performance of thin-walled rotary parts made of hard brittle material on
high-speed aerocraft cannot meet the technical requirements after semi-finished processing, in order
to compensate the physics performance, the wall thickness should be properly grinded based on the
inner surface reference in the finish machining. A processing method consisted of measuring,
calculating and grinding functions is investigated. The data of complex surface is obtained with
trigger measuring technology, and the reconstructed profile is calculated with cubic polynomial
approaching algorithm, which has fast and stable merits in suit with efficient machining. The
grinding G program is generated according to the concrete construction of machining tool. This
method has been verified by experiments.
Abstract: Laser processing of super-abrasive grinding wheel is paying a role in a truing/dressing
technique to complement mechanical methods recently. However, normal dressing/truing is difficult
owing to the toughness of metal-bond materials and high hardness of diamond abrasive. Both
geometric and mathematic models were developed to improve laser processing quality and predict
various processing parameters, such as focal offset, and incident power, and power density to
perform material removal during laser processing a metal-bond diamond grinding wheel. Various
trends of the geometrical features of dressing zone in terms of the varying focal offsets were
analyzed. Discussions were also given on dressing-zone geometry control. Experimental studies
were carried out using different processing parameters to test the effects of laser poweres on
dressing quality. Further grinding-force measurement determined the laser dressing parameters with
respect to the wheel surface conditions. The normal force FN reduces up to 20%, while tangential
force FT decreases to 7% too.The outcomes were shown well agreement with predicted results.
Abstract: The fundamental characteristics of dressing action on the polyurethane pad are
investigated via dressing by single diamond of different orientations, dressing parameters and
dressing path in this study. Experimental results show that a groove with pile-up on both side walls
forms as the diamond moves over the pad with a specific dressing depth. The resulting asperities on
the pad are strongly affected by the diamond orientation. Plowing is found to be the major
mechanism responsible for this surface topology if dressing is conducted by the face of a diamond.
On the contrary, cutting action dominates when the point of a diamond is responsible for dressing. It
is also found that dressing velocity has an insignificant effect on the groove and ridges created on
the pad. The depth of the groove is smaller than the dressing depth due to the spring back of the pad.
When the groove created is repeatedly dressed over the same track, the ridge height and groove
depth increases for each additional dressing. When two grooves cross each other, the ridges at the
four corners of the intersection grow while the depth of the overlapped area decreases. These ridges
will become the pressure enhancer of the abrasives to polish the wafer.
Abstract: The primary consumables in chemical mechanical polishing (CMP) are the polishing pad
and slurry. The polishing pad significantly influences the stability of the polishing process and the
cost of consumables (CoC). Usually a diamond pad conditioner is used to scrap off the polishing
debris from the pad top. Recently, an alternative planarization process can be achieved by polishing
with a "fixed abrasive pad" (FAP). In order to dress bumps on FAP, this paper use an amorphous
diamond, a diamond-like carbon deposited by cathode arc system as the dresser for FAP. The
amorphous diamond can produce a surface relief that ranges from a few nanometers to about 200
nanometers. With the addition of this dressing step on a rotary platform, FAP can renew its
polishing surface 10 to 100 times before the bumps are used up. The pad cost for polishing can be
reduced by at least ten folds and make FAP more desirable than slurry pad for silicon wafer
manufacturer due to its intrinsic capabilities to produce flatter wafers with high polishing rate.
Abstract: This paper aims at the development of an alterative technique for truing and dressing a
small vitrified CBN grinding wheel used for the internal finishing of small holes measuring several
millimeters in diameter. In conventional truing and dressing, a single-tip diamond dresser or a rotary
GC cup wheel dresser is employed. This levels off the improvement in the wheel truing accuracy
because the stiffness of the grinding wheel shaft with an open-sided structure is low, and the shaft is
thus deformed easily due to the truing force. In the present work, a new truing and dressing technique
is proposed in which a Nd:YAG laser beam is employed as the dresser. Experiments were carried out
with respect to the effects of the laser beam conditions (amplitude, width and frequency of pulse, and
focus offset) and the relative motion between the laser beam and CBN wheel. It was found that the
run-out of the CBN wheel was decreased significantly, and the wheel surface condition was improved
greatly after laser truing and dressing.
Abstract: The state of the wheel surface after dressing is important for processing of a surface to
the nano-order level. A laser dresser was developed using ultraviolet (UV) laser light, which
imparts no mechanical damage to the resin bond. One feature of this system is that UV laser energy
is transmitted by a special optical fiber for UV light, and is transmitted only to the resin bond. Using
this newly developed laser dresser, it was possible to ablate the resin bond to a depth of over 2
microns using a fiber with a core diameter of 200 microns.
Abstract: This paper reports a new laser conditioning method for micro-wheels with ultra-fine grit
diamond, which are used for the micro grinding of micro-aspherical optics. Resinoid-bonded
micro-wheels with ultra-fine grit diamonds are used for micro grinding. Such small wheels have the
problem of poor ground surface roughness due to their few effective cutting edges and low peripheral
speeds. In the present work, new truing and dressing methods are proposed to produce many effective
cutting edges. The new method uses the third harmonic of a Nd:YAG laser, which is suitable for
processing resinoid bond material. It was found that a SD1500B wheel treated using the new method
had a higher cutting edge density than one treated using a conventional method, the cup truer method.
A good surface roughness was obtained using the new method.