Contact Zone Force Profile and Machining Performance of Filamentary Brush1

2005 ◽  
Vol 127 (1) ◽  
pp. 217-226 ◽  
Author(s):  
R. J. Stango ◽  
V. Cariapa ◽  
M. Zuzanski

Filamentary brushing tools are used in a wide range of surface finishing processes, such as deburring, edge radiusing, polishing, and surface decontamination applications. Moreover, these tools are easily adapted to automation because the filament tips, which perform the machining operation, readily conform to the workpart surface without the need for sophisticated control systems technology. However, little is known about the material removal mechanics of filamentary brushes and, therefore, trial-and-error experimentation is often necessary before the tool is implemented in a production environment. This uncertainty of performance can be traced to a lack of understanding of the actual forces that are generated within the contact zone, that is, along the interface of the filament tip and workpart surface. Although previous experimental research has focused on the overall (i.e., resultant) brush force exerted onto the workpart, no information exists in the literature regarding the variation of force within the contact zone. Such information is essential for understanding the material removal profile within the contact zone, and could provide valuable information regarding the most active machining site along the contact surface. In this paper, a novel experiment is proposed for evaluating the force profile of filament tip forces that are generated within the contact region of a brushed surface. A specially designed workpart fixture is constructed and used in conjunction with a multiaxis force sensor for measuring the detailed force variation within the contact zone. The experiment is conducted using a wire brush at several different rotational speeds, which enables one to ascertain the role of filament inertia in the material removal process. Findings are reported which suggest that a significantly enhanced material removal rate can be achieved at a selective location within the contact zone at moderately elevated spindle speeds.

Manufacturing ◽  
2002 ◽  
Author(s):  
Robert J. Stango ◽  
Vikram Cariapa ◽  
Mark Zuzanski

Filamentary brushing tools are used in a wide range of surface finishing processes, such as deburring, edge radiusing, polishing, and surface decontamination applications. Moreover, these tools are easily adapted to automation because the filament tips, which perform the machining operation, readily conform to the workpart surface without the need for sophisticated control systems technology. However, little is known about the material removal mechanics of filamentary brushes and, therefore, trial-and-error experimentation is often necessary before the tool is implemented in a production environment. This uncertainty of performance can be traced to a lack of understanding of the actual forces that are generated within the contact zone, that is, along the interface of the filament tip and workpart surface. Although previous experimental research has focused on the overall (i.e., resultant) brush force exerted onto the workpart, no information exists in the literature regarding the variation of force within the contact zone. Such information is essential for understanding the material removal profile within the contact zone, and could provide valuable information regarding the most active machining site along the contact surface. In this paper, a novel experiment is proposed for evaluating the force profile of filament tip forces that are generated within the contact region of a brushed surface. A specially designed workpart fixture is constructed and used in conjunction with a multi-axis force sensor for measuring the detailed force variation within the contact zone. The experiment is conducted using a wire brush at several different rotational speeds, which enables one to ascertain the role of filament inertia in the material removal process. Findings are reported which suggest that a significantly enhanced material removal rate can be achieved at a selective location within the contact zone at moderately elevated spindle speeds.


2014 ◽  
Vol 1017 ◽  
pp. 812-817 ◽  
Author(s):  
Jin Liang ◽  
Ren Ke Kang ◽  
Fu Jian Ma ◽  
Jin Ting Liu ◽  
Yue Bin Yu

Lapping is widely applied to hole surface finishing. However, for small holes of high hardness material, low efficiency and unstable hole surface quality of traditional lapping cannot be ignored. In this paper, the ultrasonic transducer and horn–tool were designed by the analytical method and the finite element method (FEM). An equipment of ultrasonic lapping for small holes was developed. Vibration performance tests of developed equipment were conducted by using microscope and laser displacement sensor. The result showed that the amplitude of ultrasonic lapping equipment can meet manufacturing demand. The machining performance of the developed ultrasonic lapping equipment was also investigated by comparing the surface quality and material removal rate with traditional lapping. The result showed that the higher material removal rate and better hole surface quality can be obtained by ultrasonic lapping.


Author(s):  
Sundar Marimuthu ◽  
Bethan Smith

This manuscript discusses the experimental results on 300 W picosecond laser machining of aerospace-grade nickel superalloy. The effect of the laser’s energetic and beam scanning parameters on the machining performance has been studied in detail. The machining performance has been investigated in terms of surface roughness, sub-surface thermal damage, and material removal rate. At optimal process conditions, a picosecond laser with an average power output of 300 W can be used to achieve a material removal rate (MRR) of ∼140 mm3/min, with thermal damage less than 20 µm. Shorter laser pulse widths increase the material removal rate and reduce the resultant surface roughness. High scanning speeds improve the picosecond laser machining performance. Edge wall taper of ∼10° was observed over all the picosecond laser machined slots. The investigation demonstrates that high-power picosecond lasers can be used for the macro-machining of industrial components at an acceptable speed and quality.


1995 ◽  
Vol 117 (2) ◽  
pp. 142-151 ◽  
Author(s):  
Z. J. Pei ◽  
D. Prabhakar ◽  
P. M. Ferreira ◽  
M. Haselkorn

An approach to modeling the material removal rate (MRR) during rotary ultrasonic machining (RUM) of ceramics is proposed and applied to predicting the MRR for the case of magnesia stabilized zirconia. The model, a first attempt at predicting the MRR in RUM, is based on the assumption that brittle fracture is the primary mechanism of material removal. To justify this assumption, a model parameter (which models the ratio of the fractured volume to the indented volume of a single diamond particle) is shown to be invariant for most machining conditions. The model is mechanistic in the sense that this parameter can be observed experimentally from a few experiments for a particular material and then used in prediction of MRR over a wide range of process parameters. This is demonstrated for magnesia stabilized zirconia, where very good predictions are obtained using an estimate of this single parameter. On the basis of this model, relations between the material removal rate and the controllable machining parameters are deduced. These relationships agree well with the trends observed by experimental observations made by other investigators.


Materials ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 41 ◽  
Author(s):  
Hao Zhu ◽  
Zhaoyang Zhang ◽  
Kun Xu ◽  
Jinlei Xu ◽  
Shuaijie Zhu ◽  
...  

The fabrication of micro-holes in silicon substrates that have a proper taper, higher depth-to-diameter ratio, and better surface quality has been attracting intense interest for a long time due to its importance in the semiconductor and MEMS (Micro-Electro-Mechanical System) industry. In this paper, an experimental investigation of the machining performance of the direct and chemical-assisted picosecond laser trepanning of single crystalline silicon is conducted, with a view to assess the two machining methods. The relevant parameters affecting the trepanning process are considered, employing the orthogonal experimental design scheme. It is found that the direct laser trepanning results are associated with evident thermal defects, while the chemical-assisted method is capable of machining micro-holes with negligible thermal damage. Range analysis is then carried out, and the effects of the processing parameters on the hole characteristics are amply discussed to obtain the recommended parameters. Finally, the material removal mechanisms that are involved in the two machining methods are adequately analyzed. For the chemical-assisted trepanning case, the enhanced material removal rate may be attributed to the serious mechanical effects caused by the liquid-confined plasma and cavitation bubbles, and the chemical etching effect provided by NaOH solution.


2015 ◽  
Vol 656-657 ◽  
pp. 335-340 ◽  
Author(s):  
Fang Pin Chuang ◽  
Yan Cherng Lin ◽  
Hsin Min Lee ◽  
Han Ming Chow ◽  
A. Cheng Wang

The environment issue and green machining technique have been induced intensive attention in recent years. It is urgently need to develop a new kind dielectric to meet the requirements for industrial applications. The aim of this study is to develop a novel dielectric using gas media immersed in deionized water for electrical discharge machining (EDM). The developed machining medium for EDM can fulfill the environmentally friendly issue and satisfy the demand of high machining performance. The experiments were conducted by this developed medium to investigate the effects of machining parameters on machining characteristics in terms of material removal rate (MRR) and surface roughness. The developed EDM medium revealed the potential to obtain a stabilizing progress with excellent machining performance and environmentally friendly feature.


1999 ◽  
Author(s):  
Fuqian Yang ◽  
J. C. M. Li ◽  
Imin Kao

Abstract The deformation of the wire in the wiresaw slicing process was studied by considering directly the mechanical interaction between the wire and the ingot. The wire tension on the upstream is larger than on the downstream due to the friction force between the wire and the ingot. The tension difference across the cutting zone increases with friction and the span of the contact zone. The pressure in the contact zone increases from the entrance to the exit if the wire bending stiffness is ignored. The finite element results show that the wire bending stiffness plays an important role in the wire deformation. Higher wire bending stiffness (larger wire size) generates higher force acting onto the ingot for the same amount of wire deformation, which will leads to higher material removal rate and kerf loss. While larger wire span will reduce the force acting onto the ingot for a given ingot displacement in the direction perpendicular to the wire.


2021 ◽  
Vol 23 (2) ◽  
pp. 6-16
Author(s):  
Sergey Bratan ◽  
◽  
Stanislav Roshchupkin ◽  
Alexander Kharchenko ◽  
Anastasia Chasovitina ◽  
...  

Introduction. The final quality of products is formed during finishing operations, which include the grinding process. It is known that when grinding brittle materials, the cost of grinding work increases significantly. It is possible to reduce the scatter of product quality indicators when grinding brittle materials, as well as to increase the reliability and efficiency of the operation, by choosing the optimal parameters of the technological system based on dynamic models of the process. However, to describe the regularities of the removal of particles of a brittle non-metallic material and the wear of the surface of the grinding wheel in the contact zone, the known models do not allow taking into account the peculiarities of the process in which micro-cutting and brittle chipping of the material are combined. Purpose of the work: to create a new probabilistic model for removing the surface layer when grinding brittle non-metallic materials. The task is to study the laws governing the removal of particles of brittle non-metallic material in the contact zone. In this work, the removal of material in the contact zone as a result of microcutting and brittle chipping is considered as a random event. The research methods are mathematical and physical simulation using the basic provisions of the theory of probability, the laws of distribution of random variables, as well as the theory of cutting and the theory of a deformable solid. Results and discussion. The developed mathematical models make it possible to trace the effect on material removal of the overlap of single cuts on each other when grinding holes in ceramic materials. The proposed dependences show the regularity of stock removal within the arc of contact of the grinding wheel with the workpiece. The considered features of the change in the probability of material removal upon contact of the treated surface with an abrasive tool and the proposed analytical dependences are valid for a wide range of grinding modes, wheel characteristics and a number of other technological factors. The obtained expressions make it possible to find the amount of material removal also for schemes of end, flat and circular external grinding, for which it is necessary to know the amount of removal increment due to brittle fracture during the development of microcracks in the surface layer. One of the ways to determine the magnitude of this increment is to simulate the crack formation process using a computer. The presented results confirm the prospects of the developed approach to simulate the processes of mechanical processing of brittle non-metallic materials.


Materials ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 125 ◽  
Author(s):  
Lei Guo ◽  
Xinrong Zhang ◽  
Shibin Chen ◽  
Jizhuang Hui

Ultraviolet-curable resin was introduced as a bonding agent into the fabrication process of precision abrasive machining tools in this study, aiming to deliver a rapid, flexible, economical, and environment-friendly additive manufacturing process to replace the hot press and sintering process with thermal-curable resin. A laboratory manufacturing process was established to develop an ultraviolet-curable resin bond diamond lapping plate, the machining performance of which on the ceramic workpiece was examined through a series of comparative experiments with slurry-based iron plate lapping. The machined surface roughness and weight loss of the workpieces were periodically recorded to evaluate the surface finish quality and the material removal rate. The promising results in terms of a 12% improvement in surface roughness and 25% reduction in material removal rate were obtained from the ultraviolet-curable resin plate-involved lapping process. A summarized hypothesis was drawn to describe the dynamically-balanced state of the hybrid precision abrasive machining process integrated both the two-body and three-body abrasion mode.


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