Applications of Tool Steels Flashcards
How are ceramic tool bits formed, and what are the applications?
Primarily fine-grained Al2O3, pressed and sintered at high pressured and temperatures into insert form with no binder.
Applications: high speed turning of cast iron and steel
Not recommended for heavy interrupted cuts (rough milling) due to low toughness
Al2O3 also widely used as an abrasive in grinding
How are cermets formed, and what are their applications?
Combinations of TiC, TiN and titanium carbonitride (TiCN), with nickel and/or Md as binders.
Applications: high speed finishing and semi-finishing of steels, stainless steels, and cast irons
Higher speeds and lower feeds than steel-cutting cemented carbide grades
Better finish achieved, often eliminating need for grinding
How are synthetic diamonds formed, and what are their applications?
Sintered polycrystalline diamond (SPD) - fabricated by sintering very fine-grained diamond crystals under high temperatures and pressures into desired shape with little or no binder
Usually applied as coating (o.5mm thick) on WC-Co insert
Applications: high speed machining of nonferrous mettals and abrasive nonmetals such as fiberglass reinforced polymer, graphite and wood
Not for steel cutting
What is cubic boron nitride (cBN), and what are its applications?
Next to diamond, cubic boron nitride is the hardest material known (45 Gpa Knoop)
Fabrication into cutting tool inserts same as sintered polycrystalline diamond (SPD): coatings on WC-Co inserts
Applications: machining steel and nickel-based alloys
