Cutting-Tool Technology and Related Topics Review Questions Flashcards
What are the 2 principal aspects of cutting-tool technology?
- tool material
- tool geometry
Name the 3 modes of tool failure in machining
- FRACTURE FAILURE
- TEMPERATURE FAILURE
- GRADUAL WEAR
What are 2 principal locations on a cutting tool where tool wear occurs
- Top Face of cutting tool
- crater wear
- side/flank wear
- Tool Point
- nose radius wear
Identify mechanisms by which cutting tools wear during machining
- abrasion
- adhesion
- diffusiom
- plasticdeformation of the cutting edge
What is the physical interpretation of the parameter C in the Taylor’s tool life euqation
C repsresents the cutting speed
Identify 3 desirable properties of a cutting tool material
- Toughness to resist fracture
- hot hardness to resist temperature failure
- wear resistance to prolong life of tool
What are the principal alloying ingredients in high-speed steel
- Tungsten-type
- Molybdenum-type
What is the difference in ingredients between steel cutting grades and nonsteel cutting grades of cemented carbide
Non-cutting grades contain only WC and Co
Steel cutting grades contain TiC and/or TaC in addition to WC-Co
Identify some of the common compounds that form the thin coatings on the surface of coated carbide inserts
titanium
carbide
titanium nitride
aluminum oxide
Name the seven elements of tool geometry for a single-point cutting tool
back rake angle
side rake angle
end relief angle
side relief angle
side cutting edge angle
nose radius
end cutting angle
Name the 2 main categories of cutting fluid according to function
lubricants
coolants
Name the 4 categories of cutting fluid according to chemistry
cutting oils
emulsfied oil
chemical fluids
semichemical fluids
What are the methods by which cutting fluids are applied in a machining operation
flooding
mist appliction
manual application
What are the problems associated with the use of cutting fluids
- Can be contaminated with foreign substances
- odors and health issues
- Does not perform lubrication function due to contaminants
- Disposal of old fluids have become more costly
What are some of the probelms introduced by dry machining
- overheating
- operating at lower cutting speeds and production rates in order to prolong tool life
- absence of chip removal benefits in grinding and milling
Define machinability
Relative ease with which material can be machined using appropriate tooling and cutting conditions
What are the criteria by which machinability is commonly assessed in a production machining operation
- Tool Life
- Cutting force
- power
- surface finish
- ease of chip disposal
What are factors on which he selection of feed in a machining operation should be based
- tooling
- roughing or finishing
- constraints on feed in roughing
- surface finishing requirements in finishing
The unit cost in a machining operations is the sum of 4 cost terms. What are those terms
- cost of part handling
- cost of machining tim
- cost of tool change time
- tooling cost
Which cutting speed is always lower for a given machining operation, cutting speed for minimum cost, or cutting speed for maximum production rate? Why?
CUTTING SPEED FOR MINIMUM COST
Identify alternative ways in which cutting tool is held in place during machining
- Solid shank
- brazed inserts
- mechanically clamped inserts
