C
SECTION C — CHEMISTRY AND METALLURGY
  
METALLURGY
 C21
METALLURGY OF IRON
 C21D
HARDENING AND ANNEALING OF STEEL, IRON, OR ARTICLES MADE THEREFROM; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING MALLEABLE BY DECARBURISATION, TEMPERING, OR OTHER TREATMENTS (cementation by diffusion processes C23C)
 C21D 1/00
General methods or devices for heat treatments, e.g. annealing, hardening, quenching, tempering
 C21D 1/02
·  Hardening articles or materials formed by forging or rolling, with no further heating beyond that required for the formation
 C21D 1/04
·  with simultaneous application of supersonic waves, magnetic or electric fields
 C21D 1/06
·  Surface hardening by heating
 C21D 1/08
·  ·  with flames
 C21D 1/10
·  ·  by electric induction
 C21D 1/12
·  ·  Apparatus therefor
 C21D 1/18
·  Tempering
 C21D 1/20
·  ·  Bainitic hardening
 C21D 1/22
·  ·  Martempering
 C21D 1/24
·  ·  Low tempering
 C21D 1/26
·  Methods of annealing
 C21D 1/28
·  ·  Normalising
 C21D 1/30
·  ·  Stress-relieving
 C21D 1/32
·  ·  Soft annealing
 C21D 1/34
·  Methods of heating (C21D 1/06 takes precedence)
 C21D 1/38
·  ·  Heating by cathodic discharges
 C21D 1/40
·  ·  Direct resistance heating
 C21D 1/42
·  ·  Induction heating
 C21D 1/44
·  ·  in heat-treatment baths
 C21D 1/46
·  ·  ·  Salt baths
 C21D 1/48
·  ·  ·  Metal baths
 C21D 1/50
·  ·  ·  Oil baths
 C21D 1/52
·  ·  with flames
 C21D 1/54
·  Determining when the hardening temperature has been reached by measurement of magnetic or electrical properties
 C21D 1/56
·  with special quenching agents
 C21D 1/58
·  ·  oils
 C21D 1/60
·  ·  aqueous agents
 C21D 1/62
·  Quenching devices
 C21D 1/64
·  ·  with circulating liquids (in general F28D)
 C21D 1/66
·  ·  combined with induction heating
 C21D 1/68
·  Protective coatings for locally preventing heat treatment
 C21D 1/70
·  ·  while heating and quenching
 C21D 1/72
·  ·  during chemical change of surfaces
 C21D 1/74
·  Methods of treatment in inert gas, controlled atmosphere, vacuum, or pulverulent material (production of gases C01, C10)
 C21D 1/76
·  ·  Adjusting the composition of the atmosphere
 C21D 1/78
·  Combined heat-treatments not provided for above
 C21D 1/80
·  ·  Hardening, combined with annealing between 300° and 600°C, i.e. heat refining (Vergüten)
 C21D 1/82
·  Descaling by thermal stresses (mechanically B21, B23; chemically C23; electrolytically C25F)
 C21D 3/00
Diffusion processes for extraction of non-metals; Furnaces therefor (local protective coatings C21D 1/72; furnaces in general F27)
 C21D 3/02
·  Extraction of non-metals
 C21D 3/04
·  ·  Decarburising
 C21D 3/06
·  ·  Extraction of hydrogen
 C21D 3/08
·  ·  Extraction of nitrogen
 C21D 3/10
·  Furnaces therefor
 C21D 5/00
Heat treatments of cast-iron
 C21D 5/02
·  improving the malleability of grey cast-iron
 C21D 5/04
·  of white cast-iron
 C21D 5/06
·  ·  Malleabilising
 C21D 5/08
·  ·  ·  with oxidation of carbon
 C21D 5/10
·  ·  ·  ·  in gaseous agents
 C21D 5/12
·  ·  ·  ·  in solid agents
 C21D 5/14
·  ·  ·  Graphitising
 C21D 5/16
·  ·  ·  ·  Packing agents
 C21D 6/00
Heat treatment of ferrous alloys  [2]
 C21D 6/02
·  Hardening by precipitation  [2]
 C21D 6/04
·  Hardening by cooling below °C  [2]
 C21D 7/00
Modifying the physical properties of iron or steel by deformation (apparatus for mechanical working of metal B21, B23, B24, e.g. shot-peening B24C)
 C21D 7/02
·  by cold working
 C21D 7/04
·  ·  of the surface
 C21D 7/06
·  ·  ·  by shot-peening or the like
 C21D 7/08
·  ·  ·  by burnishing or the like
 C21D 7/10
·  ·  of the whole cross-section, e.g. of concrete reinforcing bars
 C21D 7/12
·  ·  ·  by expanding tubular bodies
 C21D 7/13
·  by hot working
 C21D 7/14
·  ·  by hot working combined with a heat treatment (treating with no heat other than that of shaping C21D 1/02; hot working methods in general B21)
 C21D 9/00
Heat treatment, e.g. annealing, hardening, quenching, tempering, adapted for particular articles; Furnaces therefor (furnaces in general F27)
 C21D 9/02
·  for springs
 C21D 9/04
·  for rails (apparatus for heat treatment of railway rails on the spot E01B 31/18)
 C21D 9/06
·  ·  with diminished tendency to become wavy
 C21D 9/08
·  for tubular bodies or pipes
 C21D 9/10
·  ·  shotgun barrels
 C21D 9/12
·  ·  barrels for ordnance
 C21D 9/14
·  ·  wear- or pressure-resistant pipes
 C21D 9/16
·  for explosive shells
 C21D 9/18
·  for knives, scythes, scissors, or like hand cutting tools
 C21D 9/20
·  for blades for skates
 C21D 9/22
·  for drills; for milling cutters; for machine cutting tools
 C21D 9/24
·  for saw blades
 C21D 9/26
·  for needles; for teeth for card-clothing
 C21D 9/28
·  for plain shafts
 C21D 9/30
·  for crankshafts; for camshafts
 C21D 9/32
·  for gear wheels, worm wheels, or the like
 C21D 9/34
·  for tyres; for rims
 C21D 9/36
·  for balls; for rollers
 C21D 9/38
·  for roll bodies
 C21D 9/40
·  for rings; for bearing races
 C21D 9/42
·  for armour plate
 C21D 9/44
·  for equipment for lining mine shafts, e.g. segments, rings, props
 C21D 9/46
·  for sheet metals
 C21D 9/48
·  ·  deep-drawing sheets
 C21D 9/50
·  for welded joints
 C21D 9/52
·  for wires; for strips
 C21D 9/54
·  ·  Furnaces for treating strips or wire
 C21D 9/56
·  ·  ·  Continuous furnaces for strip or wire
 C21D 9/58
·  ·  ·  ·  with heating by baths
 C21D 9/60
·  ·  ·  ·  with induction heating
 C21D 9/62
·  ·  ·  ·  with direct resistance heating
 C21D 9/64
·  ·  ·  Patenting furnaces
 C21D 9/66
·  ·  ·  Tower-type furnaces
 C21D 9/68
·  ·  ·  Furnace coilers; Hot coilers (cold coilers B21C)
 C21D 9/70
·  Furnaces for ingots, i.e. soaking pits
 C21D 11/00
Control or regulating devices specially adapted for heat-treatment apparatus  [2]