International Research Journal of Engineering and Technology (IRJET)
e-ISSN: 2395-0056
Volume: 04 Issue: 07 | July -2017
p-ISSN: 2395-0072
www.irjet.net
ANALYZING THE EFFECT OF DIFFERENT PROCESS PARAMETERS ON TOOL WEAR, CHIP FORMATION AND SURFACE INTIGRITY DURING CNC MILLING OF HASTELLOY C-276 Tarun Batra1 , P.S Rao2 1,2 Department
of Mechanical Engineering National Institute of Technical Teachers Training and Research Chandigarh, Punjab, India ---------------------------------------------------------------------------***---------------------------------------------------------------------------
Abstract-The paper presents the three main process
parameters such as cutting speed, feed rate and depth of cut were selected for experimentation. Machining parameters have predominant effect on the tool wear ,chip formation and surface integrity for that the manufactures needs the optimal values of operating parameters in order to reduce the experimental as well as the minimizing simulation in order to reduce machining cost. The experiments were carried out on a CNC Milling machine under dry conditions and wet conditions using PVD coated inserts and tool wear, chip formation and surface integrity is studied in process. SEM-EDS analyses were performed at different cutting conditions. The results of experiment have showed that the flank wear has most common type of wear occurred during milling of nickel based alloy. During the machining of Hastelloy C-276 high pressure and temperature was generated, micro chipping and buildup edges generated even at low cutting speed. It was evident that, when the cutting speed increased the buildup edges was vanished. During the experimentation two different types of chips formed such as serrated chips and fragment chips. With increase in cutting speed there is transition in formation of chips from serrated chips into fragment chips. Keywords: Milling, Tool Wear, Chips, PVD Coating, Surface Integrity.
1. INTRODUCTION Hastelloy C-276 (Nickel Based Super alloy) which is not easy to machine because of its high strength and low diffusive properties at high temperature. Due to present of Cr-Mo in high content it provides good resistance against pitting and crevice corrosion. It is therefore used in petro chemical industries, marine industries, chemical industries, filters, evaporators, pipes and flanges. Kadirgama et al. [1] had performed experiment on Hastelloy C-22HS to study the wear mechanisms and other microstructure defects under Scanning Electron Microscopy. Two distinct types of carbide coated inserts were used such as- coated with TiAlN /TiN and TiCN / TiN. They concluded that both types of inserts suffered from high thermal cracking and crater wear. The investigation results that performance of carbide tools coated TiAlN/ TiN cutting tool was better than tools coated with TiCN/TiN. Habeeb et al. [2] experimentally study about © 2017, IRJET
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Impact Factor value: 5.181
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the influence of tool holder’s geometry and input variables on output response studied such as tool wear and tool life when milling of nickel based alloy 242 with carbide insert having different type of coatings such as TiAlN, TiCN/TiN, TiAlN/TiN and TiCN/Al2O3. They concluded that the tool wear rapidly increases when tool holder geometry is 90º than 70º. Also observed that flank wear suffered from high abrasion wear. Kadirgama et al. [3] studied the effect of carbide insert coated with physical vapour deposition and chemical vapour deposition on surface roughness of Hastelloy C—22HS through development of surface roughness prediction model. They concluded that as the cutting speed reduced the surface roughness increases. Also the physical vapour deposition coated cutting tool performs better than chemical vapour deposition during machining of Hastelloy C-22HS. Akıncıoğlu et al. [4] experimentally studied the infleuence of input variables on surface roughness during CNC milling of Hastelloy C-22 super alloy. They selected the cutting parameters such as cryogenic treatment, cutting speed, and feed rate. They concluded that the surface roughness improved by shallow and deep cryogenic treatment applied on cementite carbide tools. They also concluded that wear resistance of tungsten carbide insert increased by shallow and deep cryogenic treatments. Zhu et al. [5] had experimentally studied that during the machining different types of plastic deformations occur at tool and work piece interface. This result in intense heat generation which causes work hardening, excessive tool wear, frequent tool changing and large amount of power consumption. Du Jin and Zhanqiang Liu [6] had carried out experiment to study the effect of cutting speed on the micro hardness, surface roughness and plastic deformation on FGH95 PM Super alloy on CNC milling using coated carbide insert. The results of experiment show that with increases in cutting speed surface roughness decreases. They concluded that different kind of surface defects appeared such as tearing, micro crack, nonmetallic dragging, void and smearing. Kaitao et al. [7] experimentally study the influence of input vaiables on the tool wear during the machining of Hastelloy C-276 by using Ti(C7N3)-based cermet insert manufactured by a hot-pressing. They concluded that the optimal cutting condition for machining of Hastelloy C-276 i.e cutting speed of 50000 mm/min, depth of cut of 0.4 mm and feed rate of 0.15 mm/rad. Tool wear ISO 9001:2008 Certified Journal
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