20-11-2012, 02:00 PM
Advanced Manufacturing Nontraditional Machining Processes
Advanced Manufacturing.ppt (Size: 670.5 KB / Downloads: 40)
Why Nontraditional Processes?
New Materials (1940’s)
Stronger
Tougher
Harder
Applications
Cut tough materials
Finish complex surface geometry
Surface finish requirements
Mechanical
Ultrasonic Machining - Cutting action is accomplished with an abrasive slurry which is driven by a tool vibrating at high frequency. The tool is the exact shape of the desired cut.
Applications
slots, blind holes, irregular shapes, and through holes.
Abrasive Water-Jet Cutting
Similar to sandblasting
Process utilizes a high velocity stream of water mixed with an abrasive as the cutting tool
Forces the mixture through a nozzle with a hole diameter of .0040” - .012”
System pressures range from 30,000 - 50,000 psi
Used to cut a variety of materials from wood to tool steel
One disadvantage is that tolerances are typically (+/- .01”)
Thermal
Laser
Laser cutting works by directing the output of a high power laser at the material to be cut. The material then either melts, burns or vaporizes away leaving an edge with a high quality surface finish.
Plasma Cutting
In this process, an inert gas is blown at high speed out of a nozzle; at the same time an electrical arc is formed through that gas from the nozzle to the surface being cut, turning some of that gas to plasma. This plasma is sufficiently hot to melt the metal and moving sufficiently fast to blow molten metal away from the cut.
Chemical
Chemical Milling
Controlled etching process
MRR about .001” cu. in per min ~ .045” cu. in hour
Process
Sample part is tested for erosion rate
Part to be “chem” machined is cleaned
Mask area you do not want to machine
Dip part in chemical solution