Proc. of. Int. Conf. on Advances in Mechanical Engineering 2010
Optimization of the Superfinishing Process Using Different Types of Stones 1
S.S. Chaudhari1, Dr. G.K. Awari2, S.S. Khedkar3
Yeshwantrao Chavan College of Engineering, Nagpur, sschaudharipatil@rediffmail.com 2 Tulsiramji Gaikwad-Patil College of Engineering, Nagpur, gkawari@yahoo.com 3 Yeshwantrao Chavan College of Engineering, Nagpur, sandip_khedkar@rediffmail.com Abstract- Super finishing is a micro-finishing process that produces a controlled surface condition on circular parts. It is not primarily a sizing operation and its major purpose is to produce a surface on a work piece capable of sustaining uneven distribution of a load by improving the geometrical accuracy. The wear life of the parts micro finished to maximum smoothness is extended considerably. Super finishing is a slow speed, low temperature, high precision abrasive machining operation for removing minute amounts of surface material In this paper critical parameters which affects surface roughness are determined. According to the design of experimentation, mathematical model for four different types of abrasive stones used is proposed. In order to get minimum values of the surface roughness, optimization of the mathematical model is done and optimal values of the examined factors are determined. The obtained results are, according to the experiment plan, valid for the testing of material MS12.
II.TESTING CONDITIONS Testing were executed on a “SUPFINA” (Germany) super finishing test rig, a pneumatically operated mounted on a standard centre lathe OKUMA (Japanese). Experiments were conducted on the cylindrical turned work-pieces of mild steel (Rocker l hardness H 30). Most experiments were conducted with the aluminum oxide stone in a vitrified bond with wax treatment. The stones were supplied with a rectangular cross section, 28 mm in width (axial direction) and 18 mm in thickness (circumferential direction) and having stone face area of 1080 mm2. The stones used contained grit size abrasives with mesh number 320 (Stone A), 500 (Stone B), 800 (Stone C) and 1000 (Stone D). The various stones used are presented in the table 1.
Index Terms —Amplitude of vibration, contact pressure, surface speed, surface roughness, optimisation
I.INTRODUCTION The super finishing process is not basically stock removal process and material removal rate reported in the literature is of least significance and the performance of the process is generally evaluated by comparing it with that of grinding. The earlier research work considered the need of a super finishing process for improving the surface finish. However, the optimal parameters were not illustrated in this work (awari, 1995) several authors have investigated the process of super finishing. (Liu, et al.,1999). Though some of these studies have considered possible optimization of parameters, only a few of them can be applied in practice. This paper is concerned with the selection of optimum super finishing conditions. Experimental results are presented that shows the effect of contact pressure, surface sped, amplitude of vibration, and grit size on super finishing performance. These results are used as a basis for selecting super finishing conditions.
Figure 1: Experimental Set-up TABLE1 LIST OF VARIOUS SUPERFINISHING STONES USED FOR EXPERIMENTATION Alumina Abrasive Stone Type make Hardness type 1
Fused white
A (320)
59.7
2
Fused white
B (500)
60.3
3
Fused white
C (600)
58.3
4
Fused white
D (1000)
60.3
The parameters varied are contact pressure, amplitude of vibration of stone, surface speed of work-piece. The work ©2010 AMAE DOI: 02.AME.2010.01.531
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