Grade

3N, 3N5, 4N, with Ta 99.99%min

Recrystallization 

95%min

Grain size

ASTM 4 or finer

Surface finish

16Rms max. or Ra 0.4 ( RMS64 or better)

Flatness 

0.1mm or 0.15% max

Tolerance   

+/-0.010" on all dimensions

Chemistry                                                                %

Designation

Chief component

Impurities  maxmium

Ta

Nb

Fe

Si

Ni

W

Mo

Ti

Nb

O

C

H

N

Ta1

Remainder

0.004

0.003

0.002

0.004

0.004

0.002

0.03

0.015

0.004

0.0015

0.002

Ta2

Remainder

0.01

0.01

0.005

0.02

0.02

0.005

0.08

0.02

0.01

0.0015

0.01

TaNb3

Remainder

3.5

0.01

0.01

0.005

0.02

0.02

0.005

0.02

0.01

0.0015

0.01

Ta2.5W

Remainder

0.005

0.003

0.002

3.0

0.006

0.002

0.04

0.015

0.005

0.0015

0.006

Ta10W

Remainder

0.005

0.003

0.002

11

0.006

0.002

0.04

0.015

0.005

0.0015

0.006