S
Second moment of area
Is a property of a 2D plane cross-section that affects its resistance to bending and deflection.
Secondary wear
Is a property of a 2D plane cross-section that affects its resistance to bending and deflection.
Self hardening properties
A property that means that when an alloy is heated above its critical temperature and left to air cool in air, it is still possible to form martensite to harden the alloy.
Semi-finishing geometry
A cutting edge that is notched to provide effective chip breaking properties.
Semi-stabilized phase
Semi-stablizied phase is achieved by the use of rapid cooling or the use of some form of catalyst. It is not the same type of phase that would be achieved by slow cooling.
Setting fixture
A fixture that is used to enable the cutting edge height to be adjusted.
T
Thermal expansion coefficient
A coefficient that refers to the fractional change in length (or sometimes in volume) of a material for a unit change in temperature.
Thermal filament
Is a term used to describe a component used inside a bulb to conduct electricity with the objective of generating heat or light.
Three rake geometry
A drill that has 3 rake faces.
Thrust
The force that acts opposite to the feed of a drill.
TiO
Titanium oxide
Tool consolidation
A reduction in the number of tools required to carry out an operation.
Shear angle
The angle at which the shear plane occurs.
Shear plane
The plane in which the shearing occurs.
Shearing force
A force incurred at the shear plane.
Spiral length
The overall length of the spiral in the flute of a drill.
Stress
Stress is the deforming force to which a body is subjected to. It can also be described as the resistance a body offers to deformation by the force.
Stub drill
A drill that is usually 2~3D in length.
Super cooling
A process in which an alloy is heated above its critical temperature and then rapidly cooled.
Tool offset
The value that represents the length of tool to the tooling datum face.
Torque
A rotational force that acts opposite to the rotation of the drill.
Torsional strength
The strength in relation to the torque experienced when drilling.
Transverse rupture strength (TRS)
A value that represents the resistance to fracturing.
Trochoidal
A machining operation that is used instead of conventional slotting. Machining is carried out in a trochoidal arc, hence the name.
Turbid
Cloudy, opaque, unclear.
Twist drill
A drill with either left or right hand flutes.