Sage Journals: Discover world-class research

Abstract

The effect of microadditions of niobium, aluminium, and a combination of the two on the austenite grain coarsening behaviour of 0·08C–0·25Si–1·5Mn steels whose nitrogen content was varied/from 0·002 to 0·02 wt-% has been studied. Modified methods of surface oxidation and thermal grooving were used in order to determine the precise prior austenite grain size in these steels with low interstitial elements. The optimum concentration of niobium which could be effectively used for restraining austenite grain growth when steels are austenitized at high temperatures has been determined. It is also demonstrated that steels containing. NbC or NbN particles exhibit similar austenite grain coarsening behaviour. Increasing the nitrogen content from 0·002 to 0·02 wt-% to give nitrogen–rich Nb(CN) particles does not help restrain austenite grain growth. However, when nitrogen was added to steels containing aluminium or aluminium and niobium, significant improvement in grain restraining behaviour was observed.

MST/120

Get full access to this article

View all access options for this article.

References

HALL

E. O.

: Proc. Phys. Soc., 1951, 64B, 747.

PETCH

N. J.

: J. Iron Steel Inst., 1953, 174, 25.

PETCH

N. J.

: Proc. Swampscott Conf., M.I.T. Press, 54.

MORRISON

w. B.

and WOODHEAD

J. H.

: J. Iron Steel Inst., 1963, 201, 43–46.

MORRISON

W. B.

: J. Iron Steel Inst., 1963, 201, 317-325.

OHTANI

et al.: Trans. Iron Steel Inst. Jpn, 1972, 12, 109.

WOODHEAD

J. H.

and WHITEMAN

J. A.

: ‘Processing and properties of low carbon steels’,145–162;1973, New York, The Metallurgical Society of AIME.

GLADMAN

: in ‘Microalloying 75’, 25-48, 1977, New York, Union Carbide Corp.

PICKERING

F. B.

: in ‘Microalloying 75’, 3-24, 1977, New York, Union Carbide Corp.

10.

VILELLA

J. R.

: Mech. Eng., 1940, 62, 293.

11.

NELSON

J. A.

: Prakt. Metallogr., 1967, 4, 192–203.

12.

KARL

and BANDELOW

: Prakt. Metallogr., 1967, 4, 582–592.

13.

R P.. KRAHE and at. DESNOUSES: Metallography, 1971, 4, 171–175.

14.

LUI

H. W.

and MAY

I. LE

: Metallography, 1971, 4, 443–450.

15.

BARRACLOUGH

D. R.

: Metallography, 1973, 6, 465–472.

16.

pLAUR

R. L.

: PhD thesis, University of Sheffield, 1974.

17.

PECINA

A. M.

: PhD thesis, University of Sheffield, 1975.

18.

WOODFINE

B. C.

: J. Iron Steel Inst., 1953, 173, 240–255.

19.

ENTWISTLE

A. R.

and SMITH

G. S.

: Trans. ASM, 1951, 43, 751.

20.

CAPUS

J. M.

: J. Iron Steel Inst., 1962, 200, 922–927.

21.

NILTAWACH

: PhD thesis, University of Sheffield, 1976.

22.

SHAMS

: PhD thesis, University of Sheffield, 1982.

23.

GLADMAN

: Proc. R. Soc., 1966, 294A, 298–309.

24.

GLADMAN

and PICKERING

F. B.

: J. Iron Steel Inst., 1967, 205, 653–664.

25.

BEPARI

M. A.

: PhD thesis, University of Sheffield, 1981.

26.

ARONSSON

B. A.

: in ‘Steel-strengthening mechanisms’, 77; 1969, London, Climax Molybdenum Co. Ltd.

Austenite grain coarsening in low–carbon manganese steels containing niobium and aluminium

Abstract

Get full access to this article

References