ISSN: ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT) Volume 3, Issue 12, June 2014

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1 Analytical Invetigation of Rake Contact, Cutting Force and Temperature in Turning G. Ravi Kumar, T. Kumara Swamy, K. Shiva Shankar, N. Madhavi Aitant profeor, Department of Aeronautical Engineering, MLR Intitute of Technology, Hyderabad Abtract- Thi project preent the application of analytical invetigation of cutting tool geometrie on the effective tre and temperature ditribution in turning AISI 4340 teel. The tool geometrie tudied under variou rake (α) angle of -5 0, and 5 repectively. The effect of variou machining parameter like cutting peed (100m/min to 300m/min) and feed rate (0.1mm/rev, 0.3mm/rev.6mm/rev and.8mm/rev) were alo invetigated. Noe radiu (Rn) and depth of cut were kept contant at 0.75mm and 4mm repectively. Finite element method were ued to model the effect different material cutting tool and finite element analyi (FEA) to tudy the tre ditribution. The reult include tre and temperature ditribution through the primary hear zone. Determination of the maximum temperature during machining proce and it ditribution along the rake urface i of much importance a it influence the tool life a well a the quality of machined part.the hear energy i created in the primary zone, where the main platic deformation take place, econd at the chip tool interface zone where econdary platic deformation take place due to the friction between the heated chip and the tool take place and the third zone where heat i generated at the work tool interface i.e., at the flank where frictional rubbing take place. Different rake angle i.e. from negative to poitive angle are conidered and modeled in PRO-E and analyzed in any (Coupled analyi- Structural and thermal). Numerou method have been generated to approach the problem uch a experimental, analytical and numerical analyi. In addition temperature meaurement technique ued in metal cutting have been reviewed. cutting parameter i.e. cutting peed, feed rate, depth of cut, tool material, and geometry and work piece material type. A. CHIP FORMATION Depending up on the tool geometry, cutting condition, and work material, a large variety of chip hape and ize are produced during different machining operation. However there are three type of chip occur: 1. Dicontinuou chip 2. Continuou chip 3. Continuou chip with built-up edge (BUE) Fig.1: Principal component and movement of a typical lathe LZ350 DEPTH OF SPEED(rpm) FEED(mm/rev) CUT(mm) Index Term finite element method (fem), Pro-E, couple field analyi, AISI 4340 teel. I. INTRODUCTION Turning proce i a common machining proce to produce cylindrical hape part. In metal cutting operation, the poition of the cutting tool i important baed on which the cutting operation i claified a orthogonal cutting? Orthogonal cutting i alo known a two dimenional metal cutting in which the cutting edge i normal to the work piece. In turning proce the work piece material i rotated and the cutting tool will travel, remove a urface layer (chip) of the work piece material, producing three cutting force component, i.e. the tangential force (Fy), which act on the cutting peed direction, the feed force (Fx), which act on the feed direction and the radial force (Fz), which act on the direction normal to the cutting peed. In orthogonal cutting no force exit in direction perpendicular to relative motion between tool and work piece. It wa oberved that the cutting force are directly depended on the Fig.2: Variable in orthogonal cutting II. INTRODUCTION TO COMPONENT The baic carbide for production of common type of carbide for machining are tungten carbide (WC) and titanium carbide (TiC), the bonding metal i cobalt (Co). A the other compound the following are the mot ued: tantalum carbide (TaC), niobium carbide (NiC) and chromium carbide (Cr3C2). Uncoated carbide are divided into three group: K-grade, P-grade and M-grade. According to the ISO tandard, K-grade i a category that include carbide cutting tool bet uited for machining cat 84

2 iron and nonferrou metal and alloy; M- grade i a category that include carbide cutting tool bet uited for machining ductile iron, harder teel, tainle teel, and high-temperature alloy; P-grade i a category that include carbide cutting tool bet uited for machining a variety of teel. Coated carbide are produced in the following way: the bae made from common carbide (K-grade, M-grade, or P-grade) i coated with a material with high hardne and excellent abraion reitance. A. CUTTING TOOL GEOMENTRY When the tool i engaged, cutting take place mainly over the ide cutting edge. The corner (or noe) and a mall portion of the end cutting edge are alo involved in the cutting. The rake face may be inclined with repect to the bae. The angle of inclination meaured in a plane perpendicular to the bae and parallel to the length of the tool i called the back rack angle. Fig 3. American Sytem of Specifying Tool Angle Tool ignature (Deignation) Back rake angle ( ): 8 o Side rake angle ( ): 10 o End relief ( ): 6 o Side relief ( ): 6 o End cutting edge ( ): 12 o Side cutting edge ( ): 30 o CHEMICAL COMPOSITION OF CARBIDE P20 in (%) Wc TiC Co Thermal and mechanical propertie of UN COATED CARBIDE P(20) Thermal conductivity (N/ec k) pecific heat(j/kg/k) 1.72 denity(kg/mm) Poion ratio 0.3 elatic modulu(n/mm 2 ) 2.6e5 DIMENSIONS Solid bar of AISI 4340 teel with 50 mm diameter, 152mm long and of 45 HRC i ued a work piece. The chemical compoition of AISI 4340 teel in percentage by weight C Si Mn P S Cr Ni Mo Fe III. INTRODUTION TO MODELING SOFTWARE A. Geometric modeling The feature-baed parametric modeling technique enable the deigner to incorporate the original deign intent into the contruction of the model. The word parametric mean the geometric definition of the deign, uch a dimenion, can be varied at any time in the deign proce. Parametric modeling i accomplihed by identifying and creating the key feature of the deign with the aid of computer oftware. The deign variable, decribed in the ketche and feature, can be ued to quickly modify/update the deign. In Pro/ENGINEER, the parametric part modeling proce involve the following tep: 1. Set up Unit and Baic Datum Geometry. 2. Determine the type of the bae feature, the firt olid feature, of the deign. Note: that Extrude, Revolve, or Sweep operation are the mot common type of bae feature. 3. Create a rough two-dimenional ketch of the baic hape of the bae feature of the deign. 4. Apply/modify contraint and dimenion to the two-dimenional ketch. 5. Tranform the two-dimenional parametric ketch into a 3D feature. 6. Add additional parametric feature by identifying feature relation and complete the deign. 7. Perform analye/imulation, uch a finite element analyi (FEA) or cutter path generation (CNC), on the computer model and refine the deign a needed. 8. Document the deign by creating the deired 2D/3D drawing 85

3 Fig.4: Aembly modeling 2. FEA SOFTWARE ANSYS ANSYS ha evolved into multipurpoe deign analyi oftware program, recognized around the world for it many capabilitie. Today the program i extremely powerful and eay to ue. Each releae hot new and enhanced capabilitie that make the program more flexible, more uable and fater. In thi way ANSYS help engineer meet the preure and demand modern product development environment. Analyi type available 1. Structural tatic analyi. 2. Structural dynamic analyi. 3. Structural buckling analyi. Linear buckling Non linear buckling 4. Structural non linearitie 5. Static and dynamic kinematic analyi. 6. Thermal analyi. 7. Electromagnetic field analyi. 8. Electric field analyi 9. Fluid flow analyi Computational fluid dynamic Pipe flow 10. Coupled-field analyi 11. Piezoelectric analyi. Importing PRO/E to Any The Initial Graphic Exchange Specification (IGES) i a vendor neutral tandard format ued to exchange geometric model between variou CAD and CAE ytem. ANSYS' IGES import capability i among the mot robut in the indutry. Moreover, becaue the filter can import partial file, you can generally import at leat ome portion of your model. ANSYS provide the following two option for importing IGES file: DEFAULT-Thi option ue an enhanced geometry databae and hould, in almot all cae, be your choice. The option wa deigned to convert IGES file, if poible, without uer intervention. The converion include automatic merging and the creation of volume to prepare the model for mehing. If the DEFAULT option encounter problem tranlating the IGES file, ANSYS will alert you to thi and activate a uite of enhanced topological and geometric tool deigned pecifically for interactive repair of imported model. ALTERNATE-Thi option ue the tandard ANSYS geometry databae, and i provided largely for backward compatibility with the previou RV52 import option. Occaionally, ANSYS will be unable to tranlate an IGES model uing the DEFAULT option and you'll be intructed to try to ALTERNATE option. The ALTERNATE option ha no capabilitie for automatically creating volume and model imported through thi tranlator will require manual repair. However, the enhanced et of topological or geometric repair tool i not available for model imported through thi tranlator; you mut ue the tandard PREP7 geometry tool to repair your model. CALCULATIONS (AT V=100, F=.1, = -5) Calculating the hear angle, the cutting force component and reultant force on the tool uing Merchant Model for Orthogonal Cutting By the depth of feed of cutting tool Depth of feed f=.25mm Rake angle of tool =-5 o Width of chip thickne b=2mm Chip thickne ratio r t =0.1 For tool teel yield tre K=472N/mm 2 UN cut chip thickne i calculated from t=0.14 V=100, n=636 The hear angle Tan = [ r t coα /1- r t inα] =0.1co(-5)/1-0.1in(-5) = [0.65] =33 i determined a: Shear force along the hear plane F =t.b.k/in N/mm 2 = 0.14*2*472/in (33) = 242 Reult force R= F /co Here olution i friction angle i calculated uing lee & Shaffer =7 R=242/co( ) 86

4 S.n o V(pee d) m/min Feed, F ISSN: Rak e DOC Forc e (N) TEMPERA TURE Work piece/tool(c ) The rate at which hear energy i expended along the hear plane i P 8 =F The rate hear energy i expanded per unit area T = ((1-.5)*334*126)/(3.8*.14*2*100) (from above formulae) = 197c i ambient temperature may be conidered from T o S.n o V(m/ min) Fee d Mm /rev Ra ke For ce Fc Celiu TOOL-FACE TEMPERATURE A=1.6 (from above formulae) L=.35 l=.3 R =.4 V Experi mental Fc Te mp (c) Experi mntl (c) =342N Cutting force component F n =R [co ( )]N/mm 2 =334 Ft=71 (THRUST FORCE) FRICTION FORCE Ff=138 SHEAR-PLANE TEMPERATURE = Tan(33)+cot(33) = 1.9 Chip Velocity Vf= 100*( SIN(33)/COS(33+5)) =69 m/min SHEAR Velocity = 100*(SIN(90+5)/COS(33+5)=126 m/min = 89 T c = ΔT + ΔT f + T o = = 362 C IV. RESULTS The reult of the imulation conducted on the tool rake angle and feed of tool. Thu, the reult repreent the highet poible tre and temperature on tool. The reult obtained for maximum deflection at different cutting parameter are The permiible deflection range from mm for finih cut to 0.9 mm for rough cut. Conidering a a cantilever (AT V=100, F=.1, = -5) R=.58 87

5 DEFORMED SHAPE NODAL DISPLACEMENT ISSN: The tree due to force and thermal obtained for the given parameter (i.e. 100 to 200m/min)are1701,4050,6359 Mpa for force and 1421,5475,5792Mpa for thermal are within the yield tre i.e. 8100Mpa 4. With FEM imulation it i poible to meaure tree on rake face at cutting tool and tool-work piece interface. 5. Comparion between analytical and experimental cutting force and temperature are good i.e. 10 to 15% variation for force 20 o 30% variation for temperature 6. At cutting peed 100, 150, 200 and 300m/min a per Taylor principle the Tool Life i etimated to be 25, 11, 6.3 and 2.7 min VON MISES REFERENCES [1] K. Weinert, Inaaki I., Sutherland J. W., Wakabayahi T., Dry machining and minimum quantity lubrication, Univerity of Dortmund, Germany, 1998, pp: [2] M. Hagiwara, S. Chen and I. S. Jawahir, Optimization of machining performance in contour finih turning operation, Thei, Univerity of Kentucky. [3] R. S. Pawade, Suha S. Johi and P. K. Brahmankar High peed machining of difficult-to-machine material: Super alloy - Inconel 718, Proceeding on High Speed Machining of Hard, Super hard Material, NUS Singapore, 2003, pp: [4] M.E. Merchant. Mechanic of the metal cutting proce, ii. Platicity condition in orthogonal cutting. Journal of Applied Phyic, vol. 16: , [5] Cutting Tool Technology by Graham T. Smith [6] Shet, C., Deng, X Finite element analyi of the orthogonal metal cutting proce. [7] Journal of Material Proceing Technology 105 (2000) [8] Metal cutting Principle by MC Shaw [9] Tool Deign by Mc Graw Hill V. CONCLUSION The cutting force calculated theoretically baed on available formulae and verified with Any oftware FEA Analyi. The tree which are calculated at the tool-tip and rake face are verified in Any. Baed on theoretical and Any analyi the following recommendation are concluded. In thi project a total of 10 experiment were carried on to find the effect of feed rate and rake angle on the cutting force during orthogonal turning of AISI 4340 teel uing P20 carbide cutting tool. From the reult of thi work the following concluion can be drawn. 1. The cutting force are increaed in negative rake angle (-5) and decreaed in poitive rake angle i.e. 0 and 5 2. With increae in peed and feed the force and temperature are increaed. AUTHOR BIOGRAPHY G. Ravi Kumar i working a an Aitant profeor in Department of Aeronautical Engineering, MLR Intitute of Technology Hyderabad. Area of interet Propulion, Fluid Dynamic, Aerodynamic T. Kumara Swamy i working a an Aitant profeor in Department of Aeronautical Engineering, MLR Intitute of Technology Hyderabad. Area of interet Propulion, Aerodynamic 88

6 K Shiva Shankar i working a an Aitant profeor in Department of Aeronautical Engineering, MLR Intitute of Technology Hyderabad. Area of interet Propulion, Structural Analyi, Aerodynamic, N. Madhavi i working a an Aitant profeor in Department of Aeronautical Engineering, MLR Intitute of Technology Hyderabad. Area of interet Propulion, Aerodynamic, Structure 89