|  | C |
SECTION C — CHEMISTRY AND METALLURGY

|  | C |
Note(s) Definitions for Section C: Alkali metals: Li, Na, K, Rb, Cs, Fr Alkaline earth metals: Ca, Sr, Ba, Ra Lanthanides: elements with atomic numbers 57 to 71 inclusive Rare earths: Sc, Y, Lanthanides Actinides: elements with atomic numbers 89 to 103 inclusive Refractory metals: Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W Halogens: F, Cl, Br, I, At Noble gases: He, Ne, Ar, Kr, Xe, Rn Platinum group: Os, Ir, Pt, Ru, Rh, Pd Noble metals: Ag, Au, Platinum group Light metals: alkali metals, alkaline earth metals, Be, Al, Mg Heavy metals: metals other than light metals Iron group: Fe, Co, Ni Non-metals: H, B, C, Si, N, P, O, S, Se, Te, noble gases, halogens Metals: elements other than non-metals Transition elements: elements with atomic numbers 21 to 30 inclusive, 39 to 48 inclusive, 57 to 80 inclusive, 89 upwards

METALLURGY

|  | C21 |
METALLURGY OF IRON

|  | C21D |
MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING, OR OTHER TREATMENTS (cementation by diffusion processes Fulltext... Hierarchy... Expanded...C23C; unidirectional solidification of eutectic materials or unidirectional demixing of eutectoid materials Fulltext... Hierarchy... Expanded...C30B)

|  | C21D 1/00 |
General methods or devices for heat treatments, e.g. annealing, hardening, quenching, tempering (furnaces in general Fulltext... Hierarchy... Expanded...F27; electric heating per se Fulltext... Hierarchy... Expanded...H05B)

|  | 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

|  | C21D 1/08 |
· · | with flames

|  | C21D 1/09 |
· · | by direct application of electrical or wave energy; by particle radiation [3]

|  | C21D 1/10 |
· · · | by electric induction

|  | C21D 1/12 |
( covered by Fulltext... Hierarchy... Expanded...C21D 1/06 )

|  | C21D 1/18 |
· | Hardening (Fulltext... Hierarchy... Expanded...C21D 1/02 takes precedence); Quenching with or without subsequent tempering (quenching devices Fulltext... Hierarchy... Expanded...C21D 1/62)

|  | C21D 1/19 |
· · | by interrupted quenching [3]

|  | C21D 1/20 |
· · · | Isothermal quenching, e.g. bainitic hardening

|  | C21D 1/22 |
· · · | Martempering

|  | C21D 1/24 |
( covered by Fulltext... Hierarchy... Expanded...C21D 1/18 )

|  | C21D 1/25 |
· · | Hardening, combined with annealing between 300 C and 600 C, i.e. heat refining ("Vergüten") [3]

|  | C21D 1/26 |
· | Methods of annealing

|  | C21D 1/28 |
· · | Normalising

|  | C21D 1/30 |
· · | Stress-relieving

|  | C21D 1/32 |
· · | Soft annealing, e.g. spheroidising

|  | C21D 1/34 |
· | Methods of heating (Fulltext... Hierarchy... Expanded...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 1/53 |
· · | Heating in fluidised beds [3]

|  | C21D 1/54 |
· | Determining when the hardening temperature has been reached by measurement of magnetic or electrical properties

|  | C21D 1/55 |
· | Hardenability tests, e.g. end-quench tests (investigating chemical or physical properties of materials in general Fulltext... Hierarchy... Expanded...G01N) [3]

|  | C21D 1/56 |
· | characterised by the quenching agents

|  | C21D 1/58 |
· · | oils

|  | C21D 1/60 |
· · | aqueous agents

|  | C21D 1/607 |
· · | Molten salts [3]

|  | C21D 1/613 |
· · | Gases; Liquefied or solidified normally gaseous material [3]

|  | C21D 1/62 |
· | Quenching devices

|  | C21D 1/63 |
· · | for bath quenching [3]

|  | C21D 1/64 |
· · · | with circulating liquids (in general Fulltext... Hierarchy... Expanded...F28D)

|  | C21D 1/66 |
( covered by Fulltext... Hierarchy... Expanded...C21D 1/62 )

|  | C21D 1/667 |
· · | for spray quenching [3]

|  | C21D 1/673 |
· · | for die quenching [3]

|  | C21D 1/68 |
· | Temporary coatings or embedding materials applied before or during heat treatment

|  | C21D 1/70 |
· · | while heating or 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 Fulltext... Hierarchy... Expanded...C01, Fulltext... Hierarchy... Expanded...C10)

|  | C21D 1/76 |
· · | Adjusting the composition of the atmosphere

|  | C21D 1/767 |
· · | with forced gas circulation; Reheating thereof [3]

|  | C21D 1/773 |
· · | under reduced pressure or vacuum [3]

|  | C21D 1/78 |
· | Combined heat-treatments not provided for above

|  | C21D 1/80 |
( transferred to Fulltext... Hierarchy... Expanded...C21D 1/25 )

|  | C21D 1/82 |
· | Descaling by thermal stresses (mechanically Fulltext... Hierarchy... Expanded...B21, Fulltext... Hierarchy... Expanded...B23; chemically Fulltext... Hierarchy... Expanded...C23; electrolytically Fulltext... Hierarchy... Expanded...C25F)

|  | C21D 1/84 |
· | Controlled slow cooling (cooling-beds for metal rolling Fulltext... Hierarchy... Expanded...B21B 43/00) [3]

|  | C21D 3/00 |
Diffusion processes for extraction of non-metals; Furnaces therefor (local protective coatings Fulltext... Hierarchy... Expanded...C21D 1/72; furnaces in general Fulltext... Hierarchy... Expanded...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 0°C [2]

|  | C21D 7/00 |
Modifying the physical properties of iron or steel by deformation (apparatus for mechanical working of metal Fulltext... Hierarchy... Expanded...B21, Fulltext... Hierarchy... Expanded...B23, Fulltext... Hierarchy... Expanded...B24, e.g. shot-peening Fulltext... Hierarchy... Expanded...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 |
( transferred to Fulltext... Hierarchy... Expanded...C21D 8/00 )

|  | C21D 8/00 |
Modifying the physical properties by deformation combined with, or followed by, heat treatment (hardening articles or materials formed by forging or rolling with no further heating beyond that required for the formation Fulltext... Hierarchy... Expanded...C21D 1/02) [3]

|  | C21D 8/02 |
· | during manufacturing of plates or strips (Fulltext... Hierarchy... Expanded...C21D 8/12 takes precedence) [3]

|  | C21D 8/04 |
· · | to produce plates or strips for deep-drawing [3]

|  | C21D 8/06 |
· | during manufacturing of rods or wires [3]

|  | C21D 8/08 |
· · | for concrete reinforcement [3]

|  | C21D 8/10 |
· | during manufacturing of tubular bodies [3]

|  | C21D 8/12 |
· | during manufacturing of articles with special electromagnetic properties [3]

|  | C21D 9/00 |
Heat treatment, e.g. annealing, hardening, quenching, tempering, adapted for particular articles; Furnaces therefor (furnaces in general Fulltext... Hierarchy... Expanded...F27)

|  | C21D 9/02 |
· | for springs

|  | C21D 9/04 |
· | for rails (apparatus for heat treatment of railway rails on the spot Fulltext... Hierarchy... Expanded...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 9/567 |
· · · · | with heating in fluidised beds [3]

|  | C21D 9/573 |
· · · · | with cooling [3]

|  | C21D 9/58 |
· · · · | with heating by baths

|  | C21D 9/60 |
· · · · | with induction heating

|  | C21D 9/62 |
· · · · | with direct resistance heating

|  | C21D 9/63 |
· · · · | the strip being supported by a cushion of gas [3]

|  | C21D 9/64 |
· · · | Patenting furnaces

|  | C21D 9/66 |
· · · | Tower-type furnaces

|  | C21D 9/663 |
· · · | Bell-type furnaces [3]

|  | C21D 9/665 |
· · · · | inverted or side-facing [3]

|  | C21D 9/667 |
· · · · | Multi-station furnaces [3]

|  | C21D 9/67 |
· · · · · | adapted for treating the charge in vacuum or special atmosphere [3]

|  | C21D 9/673 |
· · · · | Details, accessories, or equipment peculiar to bell-type furnaces [3]

|  | C21D 9/675 |
· · · · | Arrangements of charging or discharging devices [3]

|  | C21D 9/677 |
· · · · | Arrangements of heating devices [3]

|  | C21D 9/68 |
· · · | Furnace coilers; Hot coilers (cold coilers Fulltext... Hierarchy... Expanded...B21C)

|  | C21D 9/70 |
· | Furnaces for ingots, i.e. soaking pits

|  | C21D 10/00 |
Modifying the physical properties by methods other than heat treatment or deformation [3]

|  | C21D 11/00 |
Process control or regulation for heat treatments (controlling or regulating in general Fulltext... Hierarchy... Expanded...G05) [2]