machining manufacturing processes © 2012 su-jin kim gnu cutting tool materials ( 공구 재질 )...
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MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Cutting Tool Materials ( 공구 재질 )• HSS ( 하이스 )• Carbide ( 초경 )• Cermet• CBN• Diamond
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Cutting-Tool Materials
• A cutting tool has the following characteristics:1. Hardness ( 경도 ) at high temperature ~ Speed2. Toughness ( 인성 ) ~ Feed & depth3. Wear resistance ( 내마모성 )4. Chemical stability ( 화학적 안정성 )
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
HSS ( 하이스 )
HSS (High-speed steels)• HSS cuts faster than carbon tool steel, hence the name
high speed steel, but slower than carbide tools.• It is often used in power saw blades and drill bits.
TiN-Coated HSS• PVD (physical vapor deposition), TiN coating reduces
tool wear.
HSS Drill: http://www.youtube.com/watch?v=98DvSQNHLMU
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Carbides ( 초경 )
Carbides• Better wear resistance, stiffness, hot hardness• Tungsten carbide: WC + Co(for toughness) powder
metallurgy (sintered), suitable for non-ferrous, grey cast iron
• Titanium carbide: TiC + Co : TiC is suitable for steel and cast iron
Coated Carbide• Carbide + TiC, TiN, Al2O3 coated by CVD (chemical vapor deposition)• Chemically stable greatly reduce crater wear
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© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
CermetsCeramicsAluminum oxide(Al2O3), Silicon-nitride(SiN), cold pressed and hot
sinteredHot hardness ↑, toughness ↓ (chipping), thermal shock
CermetsCeramic(Al2O3) + metal binder(TiC)Hot hardness ↑, toughness ↓, thermal expansion ↑
Insert: less thermal stress, eliminate grinding by user, less setting time
http://www.youtube.com/watch?v=Om9gzgNPf80
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Diamond, CBN
Diamond (Poly crystal diamond)• Hardest material, Not good for steel
CBN (polycrystalline cubic boron nitride)• 2nd hardest material, brittle, expensive
http://www.youtube.com/watch?v=vAvfrrlMZg4
http://www.youtube.com/watch?v=mKxX50OMBd4&p=9B6D9EAE75875D9D
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Tool materials
Tool materials, feeds, and cutting speeds• Characteristics of cutting-tool materials gives a range of
cutting speeds and feeds for different applications.
Coated HSS / HSS
Feed (Toughness)
Spe
ed (
Har
dnes
s)
Coated carbideCarbide
CermetCeramic
PCDCBN
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Workpiece materials ( 소재 재질 )
• Workpiece materials and cutting speeds when Carbide tool or coated carbide tools is used for turning
Material Cutting speed (m/min)
Aluminum alloys 200-1000
Copper alloys 50-700
Cast iron, gray 60-900
Steels 50-500
Titanium alloys 10-100
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Cutting Tool Makers ( 공구 제작사 )• www.taegutec.co.kr• www.yg1.co.kr
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Cutting Fluids ( 절삭유 )
• Also called lubricants and coolants, cutting fluids.• Used extensively in machining operations to:1. Cool the cutting zone2. Reduce friction and wear3. Reduce forces and energy consumption4. Wash away chips5. Protect surfaces from any environmental attack
MachiningMachiningManufacturing ProcessesManufacturing Processes
© 2012 Su-Jin Kim GNU© 2012 Su-Jin Kim GNU
Sawing and saws ( 톱 )
• A cutting operation where the tool consists of a series of small teeth that removes material.
Belt sawDisk saw