1、.Example Fidur 23/250 E23UM250CKNPTZ12345 1Short symbol for manual arc welding 2ShortsymbolAlloy group and application1Unalloyed up to 0.4% C or low-alloyed up to 0.4% C and up to max. 5 % alloy constituents Cr, Mn, Mo, Ni in total; soft surfacing, e. g. fill-up welding, buffering layers2Unalloyed w

2、ith more than 0.4% C or low-alloyed with more than 0.4%C and up to max. 5% alloy consitutents Cr, Mn, Mo, Ni in total; running wheels3Alloyed, with the properties of hot working steel, hot working tools4Alloyed, with the properties of high-speed steel, cutting tools, mandrels, shear blades, cutters,

3、 drill bits5Alloyed with more than 5% Cr and low C-content (up to approx. 0.2%C) for scale-resistant (also against sulphurous gases) and from 12% Cr-content corrosion-resistant surfacings, e. g. valve parts, plungers, furnace parts6Alloyed with more than 5% Cr and higher C-content (approx. 0.2 - 2.0

4、% C) cutting tools, shear blades, rollers for cold rolling mills7Mn austenite with 11 to 18% Mn and more than 0.5% C and up to 3% Ni surfacings on large surfaces, e. g. wear plates, jaw plates, digging teeth, bolts8Cr-Ni-Mn-austenite crusher parts for medium stress, switch tongue, rails, water turbi

5、ne parts9Cr-Ni-steel (corrosion and heat resistant) corrosion and heat resistant surfacings10High C-content and high Cr-alloyed with and without additional carbide former, repairs on mining and steel plant equipment, surfacing on machine parts in the construction industry and agriculture, overburden

6、 excavators, sinter crushers220Co-based, Cr-W-alloyed, with or without Ni and Mo fittings of all tpyes, valve seats of exhaust valves in combustion engines, valve seats of steam engines, pump shafts and similar parts which are exposed to heavy corrosion and erosion21Carbide-based (sintered, cast or

7、folled) tools and machine parts for working in stony earth, drills and similar tools, press schrews in the ceramic industry22Ni-based, Cr-alloyed, Cr-B-alloyed valves, screws,shafts, e.g. for concrete pumps23Ni-based, Mo-alloyed with or without Cr hot working tools, contact surfaces of valves in che

8、mical apparatuses, claddings at working edges of cuttings from Ni-Cr-Mo-alloys which are used for work at high temperatures30Cu-based, Sn-alloyed bearing shell, slides, shafts, valves, housings, snail and helical gear wheels, guide and running wheels, fittings31Cu-based, Al-alloyed machine parts and

9、 fittings in the chemical industry, food, paper and electrical industry32Cu-based, Ni-alloyed distillators, sea water pipes, condensers, coolers, chemical apparatuses, heat exchangers 3SymbolTypeGWrolledGOcastGZdrawnGSsinteredGFfilledUMcoated 4Classification of hardnessHardness classHardness degree4

10、037 42 HRC4542 47 HRC5047 52 HRC5552 57 HRC6057 62 HRC6562 67 HRC7067 HRC150125 175 HB200175 225 HB250225 275 HB300275 325 HB350325 375 HB400375 450 HB 5SymbolProperties of weld metalCcorrosion-resistantGabrasion-resistantKwork-hardenable*1Nnon-magnetizablePimpact-resistantRstainlessSedge-holding (high-speed steel)Tcreep-resistant (high-speed steel)Zheat-resistant (temp. 600 C)*1The wear properties of the weld metal depend on a work-hardening after-treatment. It can be achieved by