The shearing strain undergone by the metal during chip formation, and the. A cutting tool in metal working can be defined as any tool that is used to remove metal from the work piece by means of shear deformation. Oblique cutting figure 2 is a common type of threedimensional cutting used in the machining process 12. Lower knife item 1 and upper knife item 2 have to be tempered in order to harden them and besides that, these two items have to be made out of the quality steel with high hardness. Manufacturing technology theory of metal cutting metal cutting or machining is the process of producing a work piece by removing unwanted material from a block of metal, in the form of chips.
Orthogonal cutting the cutting edge is straight and is set in a position that is perpendicular to the direction of primary motion. If you continue browsing the site, you agree to the use of cookies on this website. Explain merchant force circle along with assumptions. There are many other differences which are describe below. Manufacturing technology orthogonal and oblique cutting orthogonal cutting the cutting edge of the tool is straight and perpendicular to the direction of motion. Kim 2 cutting processes objectives product quality. The metal cutting is done by a relative motion between the work piece and the hard edge of a cutting tool. In oblique cutting the angle between the cutting edge and the direction of the tool, motion is anywhere except 90 degrees. In order to perform effective cutting operation, the cutting tool must be made of a material harder than the work material to be cut. The basic and main difference between orthogonal cutting and oblique cutting is that in orthogonal cutting, cutting edge of the tool is perpendicular to the direction of motion but in oblique cutting the cutting edge make an angle with the direction of motion. The resultant too force in metal cutting is distributed over the areas of the tool that contact the chip and workpiece.
Calculate the shear plane angle and the shear strain in the operation. The cutting forces and back forces are slightly changed by tools inclination angle. Metal machining college of engineering bhubaneswar. Jossel 1865 2 forces were obtained in lathe cutting and two types of metal cutting used in industries orthogonal cutting and oblique cutting. B oxley to predict how to cut steel was created with modifications allowing predictions of the metal cutting process with any metal. What is tool terminology and explain tool designation. In metal cutting, a wedgeshaped tool is used to remove material from the workpiece in the form of a chip. The side cutting edge angle of the tool has practically no effect on the value of cutting force or power consumed for a given depth of cut and feed. Metal cutting could be done either by a single point cutting tool or a multi point cutting tool. What is the difference between oblique and orthogonal cutting.
Stability in the dynamics of metal cutting, volume 22 1st. Types of material used for making the cutting tool. It is shown that from the standpoint of chip formation this cutting process is advisable to be treated as orthogonal free cutting with a tool whose rake is a function of the face sharpening angle and cutting edge. Analysis of orthogonal metal cutting processes tyan. The basic and main difference between orthogonal cutting and oblique cutting is that in orthogonal cutting, the cutting edge of the tool is perpendicular to the direction of motion but in oblique cutting, the cutting edge makes an angle with the d. An eulerian reference coordinate is used to describe. Orthogonal and oblique cutting mechanics pdf free download. No cutting tool is perfectly sharp, and in the idealized picture as shown in figure 2 the cutting edge is represented by a cylindrical surface joining. Explain mechanism of chip removal and derive an expression of shear angle. Sabri ozturk and erhan altan slipline metal cutting model. Lecture series on manufacturing processes ii by prof. Manufacturing engineering and technology, 3rd edition, by s.
Figure 1 shows the orthogonal cutting process basic elements. In this study, material constitutive model of hardened aisi d2 steel. Orthogonal cutting in orthogonal cutting, the cutting edge inclination is zero and chip is expected to flow along the orthogonal. The model proposed by merchant 9 has been extensively applied to metal cutting since its advent owing to the fact that it provides quite reliable data with regard to the plastic deformation in the primary shear plane, thus allowing the prediction of the imposed forces and stresses. Oblique cutting is the most common type, normally found in several. In oblique cutting, the principal cutting edge ab makes an angle with the direction of the feed. Generalized modeling of metal cutting mechanics by.
Finite element simulation of orthogonal metal cutting. Assumptions orthogonal cutting model the cutting edge is a straight line extending perpendicular to the direction of motion, and it. Two 50 minute lectures and one 2 hour lab per week. Orthogonal and oblique cutting mechanics the flow shear stress at plane ab is calculated by assuming that half of the total strain. Metal cutting is the process of removing unwanted material in the form of chips, from a block of metal. Mention the functions and properties of cutting fluids 6. Aug 22, 2014 manufacturing technology theory of metal cutting metal cutting or machining is the process of producing a work piece by removing unwanted material from a block of metal, in the form of chips. Preliminary calculation results show that the model overcomes some shortcomings of traditional finite element fe models, for example, the mesh distortion and the limitation of the separation line method in the lagrangian approach and. This article proposes an improved numerical model based on the coupled eulerianlagrangian cel formulation for the numerical analysis of metal cutting.
The paper analyzes the relationships for calculating the cutting angle in oblique free cutting of metals, which were proposed earlier by some researchers. Singlepoint tools one cutting edge turning uses single point tools point is usually rounded to form a nose radius 2. Summary the orthogonal metal cutting process for a controlled contact tool is simulated using a limit analysis. The workpiece material property is a function of temperature, strain, and strain rate in the primary and secondary shear zones. Thus tool approach angle and cutting edge inclination are zero. In orthogonal cutting operation, feed is at 90 degrees and it develops only two types of forces which are cutting force and thrust force which represents the 2d cutting action. Finite element method, orthogonal metal cutting, remeshing. The relevance of the mechanics of metal cutting to machinability.
A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Development and fabrication of sheet metal cutting machine. Apr 18, 2012 this paper presented a finite element simulation model for the analysis of aisi d2 steel turning with tialncoated inserts. The method involves an iterative procedure to determine temperature distributions in the tool from varying heat flux transfer conditions. Material removal processes machining is the broad term used to describe removal of material from a workpiece includes cutting, abrasive processes grinding. The temperature distributions determined from this procedure were compared with those obtained experimentally. Finite element analysis of the effect of cutting speeds on.
Numerical analysis of chip formation mechanisms in orthogonal. Assumptions orthogonal cutting model the cutting edge is a straight line extending perpendicular to the direction of motion, and it generates a plane surface. For a given feed and depth of cutting, the force acts on a small area as compared with oblique cutting, so tool life is less. Multiple cutting edge tools more than one cutting edge motion relative to work usually achieved by rotating drilling and milling use rotating multiple cutting edge tools. Shaw professor emeritus of engineering arizona state university new york oxford oxford university press. In this only one sharp point is able to remove the material from the specimen. Difference between orthogonal and oblique cutting mecholic. Clarendon press is closest in spirit to the mechanical engineering focus of the present work, but there have been many developments since that was first published. On the mechanics of the oblique cutting of metal strips with knifeedged tools 367 it was found in all cases that for fixed3, both types of solution became invalid due to overstressing of the vertex gbl.
Investigation into the effects of tool geometry and metal. Orthogonal metal cutting has evolved as a significant way of analyzing the mechanics involved in the art of metal cutting. The slight difference in cutting speed between the inside and outside edge of the chip can be neglected. Selecting the correct angles of cutting tools in rotating workpiece is very important. This kind of machine h as large workspace, high sleight and good manoeuvrability. Topic 3 material removal processcut theory orthogonal.
Summary the orthogonal metal cutting process for a controlled contact tool is simulated using a limit analysis theorem. Metal cutting is the process of removing unwanted material from the workpiece in the form of chips. The scheme of a oblique turning with straightedged tool and the rule for differentiating between negative and positive inclination angles are illustrated in fig. Mrr, tool wear physics of cutting mechanics force, power tool materials design for manufacturing 2. An ale threedimensional model of orthogonal and oblique metal cutting processes olivier pantale, roger rakotomalala, maurice touratier l. The last five decades has seen many researchers providing detailed insights into the cutting process. Carvill, in mechanical engineers data handbook, 1993. Jul 30, 2012 orthogonal and oblique cuttingthe two basic methods of metal cutting using a single point tool arethe orthogonal 2 d and oblique 3d.
Orthogonal cutting is a type of metal cutting angle in which the direction of the cutting tool is perpendicular to the cutting edge. Bda 3052 manufacturing technology example of problem in a machining operation that approximates orthogonal cutting, the cutting tool has a rake angle 10. Me 3217 metal cutting principles credits and contact hours. Oblique cutting differs from orthogonal cutting in that cutting velocity is perpendicular to the cutting edge in orthogonal cutting whereas in oblique cutting, it is inclined at an acute angle i to the plane normal to the cutting edge. Summary the orthogonal metal cutting process for a. All metal cutting operations involve a wedge shaped tool with a straight cutting edge, having a relative velocity with reference to the workpiece, contributing to chip formation. Describe an expression for the determination of shear angle in orthogonal metal cutting. They observed the mechanism of the metal removal by the cutting tool with large negative rake angle and the behavior of the material ahead of the tool face during cutting. Merchant pioneered the metal cutting mechanics for orthogonal cutting in about 70.
Experimental research on orthogonal cutting and oblique. Introduction the process of metal cutting is a subject of great importance to. An ale threedimensional model of orthogonal, oblique. Sheet metal cutter page 1 of 17 sheet metal cutter maximal thickness of the steel sheets that you can cut with this tool is 2mm. With respect to the materials used, the cutting tool is divided into the. This process is most important since almost all the products get their final shape and size by metal removal, either directly or indirectly. Oblique cutting the cutting edge is set at an angle the tool cutting edge inclination. According to the authors, the dead metal zone plays a crucial role in the chip formation. An ale threedimensional model of orthogonal, oblique metal cutting processes article pdf available in international journal of forming processes vol. Simulation of orthogonal metal cutting operations is very popular nowadays and there are a lot of researchers studying on this subject. Cutting edge is inclined at an acute angle to tool feed. The layer of the material with crosssection a b, is removed in the form of chips from the workpiece.
Orthogonal cutting of hardened aisi d2 steel with tialn. Paul,department of mechanical engineering, iit kharagpur. Orthogonal cutting and oblique cutting mechanical education. Yang department of mechanical engineering and applied mechanics, the university of michigan, ann arbor, michigan 48109, u. Since the metal is being cut there must be a cutting force r. Basically all machining operations are considered as either oblique or orthogonal cutting. A comparative study was done with 1006 steel, 6al4v. Single point cutting tool is the cutting tool which has only one cutting edge. Downloadtheory of metal cutting by bhattacharya pdf. Machinability study of steels in precision orthogonal cutting. These tools are made of high speed steel so these tools can be operated at high rpm. Large side cutting edge angles are lightly to cause the tool to chatter.
The basic principles are stated in the form of a primal optimization problem with an objective function subjected to constraints of the equilibrium equation, its static boundary conditions and a constitutive inequality. In a cutting process, the position of cutting edge of the tool with respect to the workpiece is important, based on which metal cutting process are classified into two categories. The instrument was used to investigate the effects of back rake angle, uncut chip thickness and cutting environments on the tool forces generated. On the mechanics of the oblique cutting of metal strips with. There are two basic types of metal cutting by a single point cutting tool. This paper discusses in detail the design and implementation of such a low cost automatic metal sheet cutting machine. As described in this chapter, since the second half this century, a lot work has been carried out for developing successful models of orthogonal metal cutting operations. A study of oblique cutting for different low cutting. In this work, cutting coefficient of aisi 1045 steel will be estimated using finite. This allows us to deal with stresses and strains that act in a plane.
On the mechanism of chip formation in oblique cutting of. This type of cutting is also known as twodimensional cutting. Kim 3 orthogonal cutting in a lathe rake angle shear angle t o. For example, three dimensional cutting mostly used in turning operations. Tool heat transfer in orthogonal metal cutting journal. Shear strength of metal along shear plane is not affected by normal stress. This paper analyzes heat flux transfer in the cutting tool in steady state orthogonal cutting.
Cutters may have straight or helical teeth, resulting in orthogonal or oblique cutting action, respectively helical teeth lower tooth load, tool forces, chatter. Then it is subjected to the specimen to perform the machining. Orthogonal cutting takes placewhen the cutting face of the tool is 90 degree to the line of action ofthe tool. Metal cutting process is a complex phenomenon yet to be fully understood and analyzed. The nature of chip formation is approximately the same for orthogonal or oblique cutting. What is meant by orthogonal cutting and oblique cutting. This cutting force r can be resolved in three mutually perpendicular directions. Introduction and nomenclature of single point cutting tool. Machine tool metal cutting types manufacturing 1997economiccensus manufacturing industry series 1997 issued november 1999 ec97m3335b u. Figure 1 depicts a typical oblique machining, such a process involves a 3 dimensional force system acting at the point of cutting which makes it. Modeling of cutting force distribution on tool edge in. Cd and m is the slope of linear plastic stressstrain relation.
In this context the advent of the finite element method has witnessed a spurt in its usage to interpret the mechanics of the orthogonal cutting process. Mallett, deputy secretary economics andstatistics administration robertj. Cutting effect of temperature lower strength, hardness and wear resistance of cutting tool lower dimensional accuracy in workpiece thermal damage to machined surface temperature gradient in tool causing distortion and poor dimensional control figure 8. Pdf on the fundamentals of orthogonal metal cutting. End cutting edge angle the function of end cutting edge angle is to prevent the trailing front cutting edge of the. Purchase stability in the dynamics of metal cutting, volume 22 1st edition. From p n rao metal cutting and machine tools, tata mcgraw hill, 2000 1. Simplified orthogonal machining inplane model of the cutting process. Difference between orthogonal and oblique cutting orthogonal cutting in orthogonal cutting, the tool approaches the work piece with its cutting edge parallel to the uncut surface and at right angles to the direction of cutting. Metal cutting, commonly called machining, is the removal. This tool is associated with the machine such as lathe and shaper machine.
Figure 2015 orthogonal tube turning ott produces a twoforce cutting operation at speeds equivalent to those used in most oblique machining operations. The orthogonal metal cutting process for a controlled contact tool is simulated using a limit analysis theorem. Orthogonal machining twoforce model cutting tool geometry is simplified from the 3d oblique geometry to a 2d orthogonal geometry. An orthogonal tube turning apparatus was constructed and validated. Difference between orthogonal and oblique cutting mech4study. An analysis of the chip geometry and the force system found in the case of orthogonal cutting accompanied by a type 2 chip has yielded a collection of useful equations which make possible the study of actual machining operations in terms of basic mechanical quantities.
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