Investigation of a New Kind of Magnetic Abrasive Grains Used for Finishing Inner-Hole Surface

2011 ◽  
Vol 487 ◽  
pp. 289-292
Author(s):  
Y.H. Ding ◽  
Xin Gai Yao ◽  
G. Ya ◽  
P. Lu

Magnetic abrasive grain is a kind of tool for magnetic abrasive finishing (MAF). The lifetime of the grains is the choke point which restricts its finishing efficiency and the surface quality processed by MAF .Therefore, a kind of magnetic abrasive grains based on Cr and Ni elements is investigated. The interrelated experimental results show: the new magnetic abrasive grains is a practical finishing tool with longer lifetime, higher finishing efficiency, better abrasive resistance compared with traditional magnetic abrasive grains. It supplies a power for promoting the development of MAF.

2021 ◽  
Vol 1018 ◽  
pp. 111-116
Author(s):  
Yan Hua Zou ◽  
Hui Jun Xie

The traditional magnetic abrasive finishing (MAF) process, the magnetic flux density at the bottom of the magnetic pole is unevenly distributed, resulting in poor uniformity of the finished surface. Therefore, it is proposed to improve the surface quality by attaching a magnetic plate at the bottom of the workpiece to improve the magnetic field distribution. It is confirmed by simulation that the magnetic field distribution at the bottom of the magnetic pole is effectively improved after the magnetic plate is attached. It is proved through experiments that the magnetic plate-assisted MAF process can obtain a smoother surface. The experimental results show that the surface roughness of the glass lens improves from 246 nm Ra to 3 nm Ra through the magnetic plate-assisted MAF process within 45min.


2021 ◽  
Vol 1018 ◽  
pp. 105-110
Author(s):  
Jiang Nan Liu ◽  
Yan Hua Zou

In this study, mainly researching the improvement of roundness of thick SUS304 stainless steel tube by interior magnetic abrasive finishing using a magnetic machining jig. The influence of reciprocating velocity of magnetic pole unit on the improvement of roundness of interior surface was studied by establishing the dynamic equation of magnetic machining jig. Experimental results showed that low reciprocating velocity of magnetic pole unit is conducive to the improvement of interior roundness of the thick SUS304 stainless steel tube. The reason is that the low reciprocating velocity of magnetic pole unit reduces the pitch of the helical motion and can produce greater finishing force of the magnetic machining jig.


2011 ◽  
Vol 675-677 ◽  
pp. 593-596 ◽  
Author(s):  
Shi Ming Ji ◽  
Ya Min Xu ◽  
Guo Da Chen ◽  
Ming Sheng Jin

Nowadays, researches concerned magnetic abrasive finishing (MAF) are becoming increasingly popular. Polishing head is one of the most important factors in the whole polishing system in which magnetic abrasive act directly on the workpiece. In this paper, two kinds of polishing heads applied in the polishing of free form surface are proposed. They are hard polishing head and soft polishing head, respectively. And some important factors are contrasted such as selfsharpening capacity, morphology distribution, and removal uniformity. Moreover, the finishing force is the key factor which is different between the two polishing heads having a great influence on polishing effect. Through comparison and analysis, the soft polishing head is better to finish free form surface. And the experimental results reflect its superiority in polishing free form surface.


2021 ◽  
Vol 5 (4) ◽  
pp. 108
Author(s):  
Andrii Zelinko ◽  
Florian Welzel ◽  
Dirk Biermann ◽  
Viktor Maiboroda

Magnetic abrasive finishing (MAF) shows a high potential for use on computerized numerical control (CNC) machine tools as a standard tool to polish workpieces directly after the milling process. This paper presents a new MAF tool with a single, large permanent magnet and a novel top cover structure for finishing the plain ferromagnetic workpieces. The top cover structure of the MAF tool, combined with an optimized working gap, ensures the effect of mechanical powder compaction, which leads to a significant increase in process capability and surface roughness reduction. The influence of the process parameters such as feed rate, equivalent cutting speed, working gap (including for three grain sizes) and the gap to the magnet was investigated. In addition, the influence of the initial surface after face milling, end milling, ball end milling and grinding on the surface quality after MAF was investigated. Furthermore, three typical surfaces after milling and MAF were analyzed. By magnetic abrasive finishing, a significant surface quality improvement of the initial milled surfaces to roughness values up to Ra = 0.02 µm and Rz = 0.12 µm in one processing step could be achieved.


2005 ◽  
Vol 04 (02) ◽  
pp. 131-150 ◽  
Author(s):  
S. C. JAYSWAL ◽  
V. K. JAIN ◽  
P. M. DIXIT

Magnetic Abrasive Finishing (MAF) is one of the non-conventional finishing processes, which produces a high level of surface quality and is primarily controlled by magnetic field. In MAF, workpiece is kept between the two poles (N and S) of a magnet. The working gap between the workpiece and the magnet is filled with magnetic abrasive particles. A magnetic abrasive flexible brush (MAFB) is formed, acting as a multipoint cutting tool, due to the effect of magnetic field in the working gap. This paper deals with theoretical investigations of the plane MAF process to know the effect of the process parameters on the surface quality produced. The magnetic field is simulated using finite element model of the process. The magnetic field is also measured experimentally to validate the theoretical results. A series of numerical experiments are performed using the finite element and surface roughness models of the process to study the effect of flux density, height of working gap, size of magnetic abrasive particles and slots (size and location) in the magnetic pole on the surface quality. Based on the results, it is concluded that surface roughness value (R max ) of the workpiece decreases with increase in flux density and size of magnetic abrasive particles. Surface roughness value (R max ) decreases with decrease in working gap. R max value also decreases when the magnet has a slot as compared to the magnet having no slot. Present study would help in understanding the effect of the various parameters on surface roughness value without doing a number of real-life experiments.


2019 ◽  
Vol 3 (2) ◽  
pp. 29 ◽  
Author(s):  
Mohammad Uddin ◽  
Vincent Santos ◽  
Romeo Marian

This paper investigates the underlying interplay between the key process parameters of magnetic abrasive finishing (MAF) in improving surface quality. The five process parameters considered were the working gap, rotational speed, feed rate, abrasive amount, and abrasive mesh when MAFed independently with two abrasive particles—SiC and Al2O3. A series of experiments were conducted with an in-house built MAF tool. Based on the main effect results, a model predicting roughness reduction was developed. Results show that surface quality improvement and the underlying dominant process parameters seem unique to the abrasive type used. When MAFed with SiC, the abrasive quantity and rotational speed influence the most. On the other hand, when MAFed with Al2O3, the trend is different to SiC, i.e., the abrasive mesh size and the working gap are dominant. The prediction model was well validated by independent experiments, indicating its accuracy in estimating and optimizing the process outcome. MAF is a simple process with a complex interplay between parameters. This is very crucial when abrasive type, size, and amount to be used are concerned, which warrants a deeper investigation in terms of underlying dynamics, interactions, and the deformation of abrasive, magnetic, and workpiece materials.


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