Basic workpiece materials

Glossary

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.

 

Sharp edge

The term sharp edge refers to a cutting edge that does not have any honing.

 

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.

 

Shoulder milling

A machining process in which 90 deg walls can be achieved.

 

Side cutting edge angle

When turning, the side cutting angle refers to the angle between the cutting edge that enters the work in the direction of tool movement and a line perpendicular to the axis.

 

 

T

Table

Table refers to the base of a machine that is used to attach the workpiece to.

 

Taper collet

A taper collet is a collet that has its grip in a taper form.

 

Tapping

Tapping is a machining method in which threads are generated.

 

Tensile strength

Easiness to conduct heat.

 

Thermal conductivity

The value found by dividing maximum load applied on a material that is stretched until being cut by the material sectional area.

 

Thermal Cracks

Separations in the cutting edge visible perpendicular to, and then parallel to the cutting edge due to thermal stress and thermal fatigue in interrupted cuts.

 

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.

 

 

 

Sintering

A process of heating a material and bonding its powder particles or compressed powder particles.

 

Slotting

A machining method used for generating slots.

 

Solid end mill

An end mill with the cutting edge, neck and shank made of the same material (high-speed steel or cemented carbide).

 

Solution treatment

A treatment that is used to forcibly maintain an alloy element dissolved in a metal.

 

Spindle

A rotation axis of a machine, on which a cutting tool or a workpiece is mounted.

 

Spiral length

The overall length of the spiral in the flute of a drill.

 

Straight collet

A straight collet is a collet that has a straight grip.

 

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.

 

Surface treating

Consists of a number of processes in which chemical elements permeates into the workpiece. Coating however is a process in which chemical elements are applied onto the outer surface of the workpiece.

 

Swarf

Swarf is a term that is often used to describe the chips developed when machining is carried out.

 

 

 

 

 

 

TiO

Titanium oxide

 

Tool consolidation

A reduction in the number of tools required to carry out an operation.

 

Tool offset

The value that represents the length of tool to the tooling datum face.

 

Tool post

A table to which tool holders or boring bars are fixed when turning.

 

Tooling

To prepare fixtures, cutting tools and cutting data that are necessary for machining.

 

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.

 

Toughness

A property of being strong and not easily

broken by external force.

 

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.