Mec130 - E Flashcards
What is the equation for feed rate
fr = Vc/Ns Vc = tool speed Ns = rotation speed (rpm)
What causes adhesive wear
Tangible force applied leads to shearing force.
Production method for tubes and pipes
Centrifugal Casting
Two causes of continuous chip
Ductile material
High cutting speed
What is a build up edge chip
Layers of material are deposited on the tool tip (hence ‘build up’)
What are the issues associated with build up edge chips
As the chip becomes larger, it becomes unstable and can deposit material on the workpiece surface, leading to a poor surface finish
How to avoid build up edge chip
Decrease depth of cut,
Increase rake angle,
Use a sharper tool
How much time does a workpiece spend in a machine
5% of production time
What is the equation for green compact density
Pg = Ps(1- delta L/L)^3
Where deltaL/L is the linear shrinkage
Why can electroplating not be used for medals
Bronze is an alloy and so cannot be electroplated
How would you cost a sintered part in bronze
Cloning as medals are essentially a coin
What are the four steps for powder metalurgy?
Powder production, blending, compression, sintering
what is the minimum wall thickness for die casting
0.5mm
What can too large a fillet radius cause.
hot spots that can result in cavities or porosity
How can the porosity of cast parts be reduced
Heat treatment, removal of gasses from molten metal.
