CARPENTER® alloy 20Cb-3® (UNS N08020)


Ni 35, Fe 37, Cr 20, Cu 3.5, Mo 2.5 Mn 2.00 C 0.07 Si 1.00 Cu 3.5 S 0.035 P 0.045


High Performance Alloys stocks and produces this grade in the following forms: Bar, wire, sheet, plate, coil, fasteners and forgings. Request quote on this grade.

Overview

Alloy 20 is a highly alloyed iron-base nickel-chromium-molybdenum stainless steel developed primarily for use in the sulfuric acid related processes. Besides sulfuric acid related processes, some typical corrosion resistant applications for the alloy include chemical, pharmaceutical, food, plastics, synthetic fibers, pickling and FGD systems plus many others.

Although normally considered a stainless steel, it has been classified as a nickel base.

Specifications

Form

Standard

Metal Type

UNS N08020

Bar

ASTM B473

Wire

ASTM B471

Sheet

ASTM B463

Plate

ASTM B463

Fitting

ASTM B366

Forging

ASTM B462

Weld Wire

ER320LR

Weld Electrode

E320LR


Chemistry

Chemical Requirements

Ni

Cr

Mo

Mn

C

Si

Fe

Max

38.00

21.00

3.00

2.00

0.07

1.00

Bal.

Min

32.00

19.00

2.00


Tensile Data

Mechanical Property Requirements

Ultimate Tensile, min.

Yield Strength,min. (0.2% OS)

Elong. in 2 in. ( 50.8 mm), min.%

R/A min.

Hardness

Cold Finished/Annealed

Min

80 KSi

35 KSi

30.0

50.0

Max

Min

551 Mpa

241 MPa

Max

Hot Finished/Annealed

Min

80 KSi

35 KSi

30.0

50.0

Max

Min

551 MPa

241 MPa

Max


Machining

MACHINING DATA
Carbide tools are suggested
for rates better than 50% of Type 304.
Machining Type Suggested starting rates are:
Single Point turning : Roughing - 0.15" depth, 0.015"/rev feed -175 SFM
Finishing - 0.025" depth, 0.007"/rev feed - 200 SFM
Drilling : 1/4" Dia hole - 0.004"/rev feed - 60 SFM
1/2" Dia hole - 0.007"/rev feed - 60 SFM
3/4" Dia hole - 0.010"/rev feed - 60 SFM
Reaming : Feed - same as drilling - 100 SFM
Side and Slot Milling : Roughing - 0.25" depth - 0.007"/tooth feed - 125SFM
Finishing - 0.050" depth - 0.009"/tooth feed - 140SFM
These rates are for carbide tools,
Type C-2 for roughing, drilling and reaming.
Type C-3 for finishing.

 

CARPENTER® and 20Cb-3® are registered trademarks of Carpenter Technology.