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
STUDIES ON MACHINING PARAMETERS OF HOT MACHINING PROCESS USING AISI4140 MATERIAL Jagjit Singh M. Tech. Mechanical Engineering, LR Institute of Engineering & Technology Solan, H.P, India ---------------------------------------------------------------------***---------------------------------------------------------------------
Abstract - The experiment is conducted on conventional
lathe. The temperature is controlled by a infra -rate thermometer and flame heating system. The statistical analysis is done by Taguchi method. Taguchi designs provide a powerful and efficient method for designing products that operate consistently and optimally over a variety of conditions. The primary goal is to find factor settings that minimize response variation, while adjusting the process on target. A process designed with this goal will produce more consistent output. A product designed with this goal will deliver more consistent performance regardless of the environment in which it is used. Taguchi method advocates the use of orthogonal array designs to assign the factors chosen for the experiment. The L9 orthogonal array of a Taguchi experiment is selected for four parameters (speed, feed rate, depth of cut and temperature) with three levels (low, medium, and high) in optimizing the hot machining turning parameters on lathe.
Key Words: Surface roughness, MRR (Material removal
was found to be significant on the surface finish due to surface hardening of steel.
1.1 DIFFERENT METHODS OF HEATING Different heating methods use for heating work piece in hot machining are
1.1.1 Furnace heating Work piece is machined immediately after being heated in the furnace to required temperature.
1.1.2 Resistance heating The entire work piece is heated by passing current either through the work piece itself or through resistance heaters embedded in the fixtures.
rate), Orthogonal array, Analysis of variance (ANOVA), GreyTaguchi Technique.
1.2.3 Flame heating
1 INTRODUCTION
In this method, work piece material immediately ahead of the cutting tool is heated by welding torch moving with the tool. Multi-flame heads can be used for large heat inputs.
The basic of hot machining operation is to first soften the work piece is by preheating and thereby shear strength gets reduced in the vicinity of the shear zone. The use of hot machining has become very useful in the machining of high strength temperature-resistant (HSTR) alloys. Hot machining has two functions to perform, one, to machine some HSTR alloys which are un Machninable in the conventional machining method. Second, to improve tool life this eventually improves the production rate. There are various techniques of hot machining which are subjected to requirements. The penetration of heat should be such that the shear zone is appreciably affected. Input rate of heat must be commendably high, so as to temperature sufficiently and quickly. Thermal damage done to work piece through distortion should be minimum. The installation and operation cost should be minimum. The operators in the operation should take safety measures into account. Temperature control should be quickly obtained. The obtained results indicate that the feed rate was found to be the dominant factor among controllable factors on the surface roughness, followed by depth of cut and tool’s nose radius. However ,the cutting speed showed an insignificant effect. Furthermore, the interaction of feed rate/depth of cut Š 2017, IRJET
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Impact Factor value: 5.181
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1.2.4 Arc heating: In this method, the work piece material immediately ahead of the cutting tool is heated by an electric arc drawn between the work piece and the electrode moving with the tool. To prevent wandering a magnetic field can be imposed to direct the arc.
1.2.5 Plasma arc heating: In this method, the work piece is heated using plasma arc just above the tool tip. In this method very high heat is produced. Heating can be limited to a very small surface area.
1.2 CUTTING TOOLS The most common tool materials that are used include the following: 1. High-speed steel (HSS) 2. Carbide ISO 9001:2008 Certified Journal
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