Nonresulfurized carbon steel (1084)

Nonresulfurized

Carbon Steels / 207

1084 Chemical Composition.

AISI and UNS: 0.80

to

0.93 C, 0.60 to

0.90 Mn. 0.040 P max. 0.050 S max LINS ~10810; ASTM (C108-1); SAE 5303. J412. J-II-I: (Ger.) DIN

Heat to II75 “C (2lSO”Fl

Forge Normalize l Anneal l Rough machine l Austenitize 9 Quench l Temper l Finish machine l

Do not forgebelow

815 “C (l5OO’F)

1084: Hardness

Recommended Normalizing.

Heat Treating

Practice

average

Heat to 870 “C (1600 “F). Cool in air

Annealing. Heat to 8 I5 “C ( I500 “F). Furnace cool to 650 “C ( I 200 “F). at a rate not to exceed 28 “C (SO “F) per h Hardening. Heat to 8 IS “C ( I500 “F). Carbonitriding and austemperinp are suitable surface hardening processes. Quench in water or brine. Rounds under 6.35 mm (0.25 in.) diam may be oil quenched for full hardness Tempering.

Asquenched hardness of approximately ness can be reduced by proper tempering

Austempering.

Sequence

l

Characteristics. Composition nearly identical to that of 1080. Asquenched hardness near 65 HRC. As carbon content increases. there is a padual increase in amount of free carbides. This enhances abrasion resistance and decreases ductility. Forgeability is good. Weldabilitj is very poor Forging.

Processing

Forgings

Similar Steels (U.S. and/or Foreign). A510, A576; FED QQ-S-700 I .0647

Recommended

65 HRC.

Hard-

Very thin sections, because of relatively low hardenability can be austempered. using the technique for 1060. Thin sections (typically springs) are austempered. Results in a bainitic structure and hardness of approximately 46 to 52 HRC. Austenitize at 8 I5 “C ( IS00 “F). Quench in molten salt bath at 3 I5 “C (600 “F). Hold at temperature for at least I h. Air cool. No tempenng required

based

vs Tempering on a fully quenched

Temperature. structure

Represents

an