As a result, it is concluded that, as temperature is approximately proportional to the product of cutting speed and depth of cut, the shear angle depends on the product of cutting speed and depth of cut .
How does shear angle affect cutting force?
Since the shear strength is applied across this area, the shear force required to form the chip will decrease when the shear plane area is decreased . This tends to make machining easier to perform, and also lower cutting energy and cutting temperature.
Does the cutting force increase with the following why a increasing depth of cut B decreasing rake angle?
It is logical that the cutting force increases as the depth of cut increases and rake angle decreases . Deeper cuts remove more material, thus requiring a higher cutting force. As the rake angle, α, decreases, the shear angle, φ , decreases (see Eqs.
Why is it not always advisable to increase the cutting speed in order to increase the productivity?
Why is it not always advisable to increase the cutting speed in order to increase the production rate? ... Higher cutting speeds also increase flank wear , and will result in high temperatures at the tool-workpiece interface.
Is material ductility important for machinability explain?
21.15 Is material ductility important for machinability? ... Ductility directly affects the type of chip produced which, in turn, affects surface finish, the nature of forces involved (less ductile materials may lead to tool chatter), and more ductile materials produce continues chips which may not be easy to control.
What is angle of shear?
The angle between the planes of maximum shear , which is bisected by the axis of greatest compression.
What is the formula of shear angle?
In a chip formation process, the shear plane angle is the angle between the horizontal plane and the shear plane. It is calculated by this equation: Tan angle is equal to chip ratio cosine rake angle divided by 1 minus chip ratio sine rake angle.
What is rake angle in cutting tool?
Rake angle is a cutting edge angle that has large effects on cutting resistance, chip disposal, cutting temperature and tool life . Increasing rake angle in the positive (+) direction improves sharpness. Increasing rake angle by 1° in the positive (+) direction decreases cutting power by about 1%.
What are the major properties required of cutting tool materials Why?
What are the key characteristics that a cutting tool must have and why? Hot hardness , so that hardness, strength, and wear resistance of the tool are maintained at the temp encountered in machining operations. ... reduce friction and wear, thus improving tool life and surface finish of the workpiece.
What is orthogonal cutting?
The term “orthogonal cutting” has been coined1 to cover the case where the cutting tool generates a plane surface parallel to an original plane surface of the material being cut and is set with its cutting edge perpendicular to the direction of relative motion of tool apd workpiece.
Why does temperature is an important effect on tool life?
Temperature has a large effect on the life of a cutting tool for several reasons. First, all materials become weaker and less hard as they become hotter ; therefore, higher temperatures will weaken and soften an otherwise ideal material. ... 22.24 Ceramic and cermet cutting tools have certain advantages over carbide tools.
How does hardness affects the machinability of a metal?
2 Machinability of metals. Machining forces tend to increase with hardness . ... A harder surface layer increases the resistance to abrasive machining. In addition to the direct effect of hardness, abrasivity of a protective coating on a work-material increases rate of wear of the abrasive tool.
How do you calculate material removal rate?
The material removal rate in a work process can be calculated as the depth of the cut, times the width of the cut, times the feed rate . The material removal rate is typically measured in cubic centimeters per minute (cm 3 /min).
What is angle of shearing resistance?
angle of shearing resistance (internal angle
What is shear angle in orthogonal cutting?
(a) shear plane and the cutting velocity . (b) shear plane and the rake plane. (c) shear plane and the vertical direction. (d) shear plane and the direction of elongation of crystals in the chip.
What is the relation between angle of shear and angle of twist?
The first thing might be obvious: the more angle of twist, the larger the shear strain (denoted by the Greek symbol gamma, as before). Second, and this is the big difference between axial-loaded structures and torque-loaded ones, the shear strain is not uniform along the cross section.
