228_14

UDC

669.14

: 643,226

1643,942

)

Second Reprint SEPTEMBER

(

IS:228(Partl4)-1988

1996 )

( Reaffirmed 1994 )

Indian

METHODS PART

14

FOR CHEMICAL

DETERMINATION

OF CARBON

(FOR

I. scope -This steels and alloy

Standard

CARBON

ANALYSIS

BY THERMAL

0.005 TO 2.000

OF STEELS CONDUCTIVITY

standard ( Part 14 ) covers a method for determination steels in the range of 0’005 to 2’000 percent.

of Carbon by Thermal

2. Determination

Conductivity

METHOD

PERCENT)

of

carbon

in all

types (

Method

2.1 Oofh’ne offhe MethodThe sample is burnt in a stream of oxygen in presence of a met; accelerator.

The carbon dioxide formed is selectively adsorbed on the molecular sieve at a tempera ture apd released by heating at 300°C. The detector is a thermistor cell which senses the differenc# between thermal conductivity of the carrier gas ( with helium specially for extra-ldw carbon, ant oxygen in other cases ) and that of the carrier gas containing carbpn dioxide.

This difference i proportional to carbon content of the sample.

3. Reagents 3.1 Oxygen

99’6 percent

( 01) -

3.2 Helium-

99’5 percent

1.3 Ascarite

or Soda-Lime

.4 Magnesium

pure, Min.

pure, Min. -

Perch/orate

0’80 mm-2’0 -

0’80 mm-20

Trap -

containing

,7 Carbon Dioxide

Converter

8 Accelerators

-

coppei,

manganese

dioxide

containing

-

tin or iron granules,

consisting Apparatus - Any analyser blumn and thermistor type detector.

-

The

samples shall

Conforming

( MnOt

copper oxide

crucibles of 9 Crucibles -pre-ignited mibustion tube of the induction furnace.

Sampling Standard.

mm.

( rd 7 1’84 ) -

.S Concentrated Sulphuric Acid ulphuric acid ( second revision )‘. .6 Sulphur

mm.

be drawn

maintained

dimensions

induction

and

‘Specification

fo

accommodated

in

).

free from carbon

precise

of

to IS : 263-1977

and sulphur. which

furnace,

prepared

at 300°C.

may

molecular

as prescribed

be

sieve,

in

chromatographic

the

relevant

Indian

6, Procedure

6.1 Standardization 6.1 .I Switch on the stability of the cell.

instrument

6.1.2 Start the flow of purified rate of 1 000 - 1 500 ml/minute.

Adopted

22 December

for 4 hours

oxygen

before

analyzing

gas and pass it

continuously

I

I .

BUREAU MANAK

OF BHAVAN.

INDIAN 9 BAHAOUR NEW OELHI

STANDARDS SHAH 110002

through

attaining

the

Gr 1

@ June 1988. BIS

1987

the samples for

ZAFAR

MARG

thermal

system at the

IS : 228

(Part

44 ) - 1988

6.1.3 Transfer into the pre-ignited crucible 1’00 g standard in the range of interest and add 1’0 g accelerator.

6.1.4

Insert

the crucible

into the induction

furnace,

wait

sample which

for 30 seconds

has a value

and start the induction.

6.1.5 Note the percentage carbon, and adjust if necessary, the standardization until value of carbon for the standard sample is obtained and with the desired reproducibility.

6.2

Of carbon

the certified

For Sample

6.2.1 acetone, 6.2.2

Transfer benzene Insert

1 g of accurately weighed sample previQusly washed or ether) thrice and dried at 100&5”C OF the crucible

into the induction

7. Reproducibility

-

furnace

rf, 0’000 2 percent

and proceed or f

until

the percentage

0’5 percent

EXPLANATORY

with organic solvent ( like and add 1’0 g of accelerator.

of carbon

of carbon

present

is read out.

whichever

is greater.

NOTE

The first revision of IS : 228-1959 covered the chemical analysis of plain carbon and low alloy was again revised to make it comprehensive steels along with pig iron and cast iron. This standard in respect of steel analysis and to exclude pig iron and cast iron analysis which is being covered in 8 The second revision of IS : 228 was issued in parts covering chetnical analysis separate standard. of steels.

This part ( Part 14 ) covers chemical analysis of ca!bon in steels by thermal conductivity method.

Determination of carbon in steels by infra-red combustion .method is being covered in However, determination of carbon in steels by volumetric another part of series of this standard.

The other parts and gravimetric methods has been prescribed in Part 1 and Part 4 of this standard. of this series are : Determination of darbon ( Part 1 )-1988 cent ) ( third revision) Determination of ( Part 2 )-1987 method (third revision) ( Part 3 )-1987

Determination

Determination ( Part 4 )-1987 ( third revision ) ( Part 5 )-1987 nickel

Determination > 0’1 percent

by volumetric

manganese

plain

carbon

of phosphorus

by alkalimetric

of

gravimetric

carbon

by

(for

and

method

by persulphate

( Part 7)-1974 Determination of molybdenum 3 1 percent) ( second revision ) Determination ( Part 8 )-1975 (second revision )

of silicon

Determination ( Part 9 )-1975 revision )

of sulphur

by

in plain

carbon

0’05 to 2’50 persteels

( gravimetric oxidation

(for

> 0’1 percent) )

method

method

method

by arsenite

( third revision )

( for carbon

a-bentoinoxime

by the gravimetric

carbon

low alloy

method

of nickel by dimethylglyoxime ) ( third revision )

( Part 6 )-1987 Determination of chromium 3 0’1 percent ) ( third revision )

(

in

method

method (for

( for

chromium

( for molybdenum

silicon

steels by evolution

Z 0’1 percent) method

(second

Part 10 )-1976

Determination of molybdenum by thiocyanate ( photometric) method molybdenum up to 1 percent ) in low and high alloy steels (second revision )

( Part 11 )-1976 Determination of silicon by photometric method in carbon alloy steels ( for silicon 0’01 to 0’05 percent ) (second revision) ( Part 12 J-1976 Determination of manganese by periodate and high alloy steels ( for manganese up to 2 percent ( Part 13)-1982

Determination

)

steels

( photometric ) method ( second revision)

(for

and

low

in low

of arsenic 2 Reprography

Unit,

DIS,

New Delhi,

India