Sage Journals: Discover world-class research

Abstract

The commercial 7000 series aluminium alloys are based on medium strength Al–Zn–Mg and high strength Al–Zn–Mg–Cu systems. The medium strength alloys are weldable, whereas the high strength alloys are non-weldable. This is because the amount of copper present in these alloys gives rise to hot cracking during solidification of welds. As a result, the high strength Al–Zn–Mg– Cu base alloys are not used for applications where joining of components by welding is an essential step. In the present study, using a combination of qualitative Houldcroft test and quantitative Varestraint test, it is shown that a small addition of scandium to the commercial 7010 alloy reduces the hot cracking susceptibility during solidification of welds produced by the gas tungsten arc welding process. The improvement in weldability is found to be the result of the considerable grain refinement in the weld structure following the scandium addition. The results of microhardness and tensile tests are further described within the context of the present work to demonstrate that the 7010+Sc welds also exhibit a combination of improved strength and ductility.

Keywords

AL ALLOY 7010 SC ADDITION GRAIN REFINEMENT WELDABILITY

Get full access to this article

View all access options for this article.

References

‘Welding handbook’, 7th edn, Vol. 2, 114–148; 1978, FL, USA, American Welding Society.

Kou

: Weld. Res. Counc. Bull., 1986, 320, 1–25.

Kou

: ‘Welding metallurgy’, 2nd edn; 2002, John Wiley & Sons, Inc.

Dudas

J. H.

and Collins

F. R.

: Weld. J., 1966, 45, 241s–249s.

Kant

K. G.

: Proc. Conf. on ‘Weldable Al-Zn-Mg alloy’, Cambridge, September 1969, The Welding Institute, 110–118.

Kou

and Le

: Weld. J., 1986, 65, 305s–313s.

Zakharov

V. V.

: Met. Sci. Heat Treat., 1995, 5, 203–207.

Kou

: Proc. Conf. on ‘Recent trends in welding science and technology’, (ed. S. A. David and J. M. Viteck), Gatlinburg, TN, USA, 1989, 137–146.

Davies

G. J.

and Garland

J. G.

: Int. Mater. Rev., 1975, 20, 83–105.

10.

Irving

: Weld. J., 1997, 76, 53–57.

11.

Mousavi

M. G.

, Cross

C. E.

and Grong

: Sci. Technol. Weld. Joining, 1999, 4, 381–388.

12.

Ishchenko

A. Ya.

, Chapor

V. O.

and Yavorskaya

M. R.

: Paton Weld. J., 2000, 11, 15–17.

13.

Norman

A. F.

, Hyde

K. H.

, Costello

, Thompson

, Birley

and Prangnell

P. B.

: Mater. Sci. Eng., 2003, 354, 188–198.

14.

Lathabai

and Lloyd

P. G.

: Acta Mater., 2002, 50, 4275–292.

15.

Kramer

L. S.

, Track

W. T.

and Fernandes

M. T.

: Adv. Mater. Process., 1997, 10, 23–24.

16.

Filatov

Y. A.

: Weld. World, 1994, 33, 428–429.

17.

Yushchenko

K. A.

, Ishchenko

A. Y.

, Tretyak

N. G.

, Lozovskaya

A. V.

and Sklabinskaya

I. E.

: Weld. World, 1995, 35, 48–51.

18.

Elagin

V. I.

, Zakharov

V. V.

and Rostova

T. D.

: Mater. Sci. Heat Treat. (USSR), 1983, 25, 546–600.

19.

Torma

, Kovacs-cseteny

, Turmezey

, Ungar

and Kovacs

: J. Mater. Sci., 1989, 24, 3924–3926.

20.

Novikov

I. I.

and Grushko

O. E.

: Mater. Sci. Technol., 1995, 11, 926–932.

21.

Mukhopadhyay

A. K.

, Reddy

G. M.

, Prasad

K. S.

, Kamat

S. V.

, Dutta

and Mondal

: Staley Honorary

J. T.

Symp. on ‘Aluminium alloys’, ASM Materials Solutions Conference, 2001, Indianapolis, USA.

22.

Houldcroft

P. T.

: Br. Weld. J., 1955, 2, 471–175.

23.

Ignatiev

V. G.

and Rabkin

D. M.

: Automatic Weld., 1994, 39–42.

24.

Lundin

C. D.

, Lingenfelter

A. C.

, Gratke

G. E.

, Lessman

G. G.

and Mathews

S. T.

: ‘The Varestraint test’, Welding Research Bulletin No. 280, The Welding Institute, Cambridge, August 1982.

25.

Reddy

G. M.

, Gokhale

A. A.

, Prasad

K. S.

and Prasad Rao

: Sci. Technol. Weld. Joining, 1998, 3, 208–212.

26.

Lin

D. C.

, Wang

G.-X.

and Srivatsan

T. S.

: Mater. Sci. Eng., 2003, A351, 304–309.

27.

Cross

C. E.

, Grong

and Mousavi

: Scripta Mater., 1999, 40, 1139–1144.

28.

Gutierrz

, Lippold

J. C.

and Lin

: Mater. Sci. Forum, 1996, 217–222, 1691–1696.

29.

Jankiram

G. D.

, Reddy

G. M.

and Sundaresan

: Pract. Metallogr., 2000, 37, 276–287.

30.

Metz

S. A.

and Fleming

M. C.

: Trans. Am. Foundrymens Soc., 1970, 78, 453–460.

31.

Borland

J. C.

: Br. Weld. J., 1960, 7, 508–572.

32.

Tanaka

, Yoshinda

and Kambayash

: Proc. 2nd Int. Conf. on ‘Aluminium weldments’, Munich, Germany, May 1982, I9·1–I9·10.

33.

Cross

C. E.

, Tack

W. T.

, Loechel

L. W.

and Kramer

L. S.

: Proc. of Materials Weldability Symposium held in conjunction with Materials Week, Detroit, MI, October 1990, ASM International, Materials Park, OH, 275–279.

Influence of scandium on weldability of 7010 aluminium alloy

Abstract

Keywords

Get full access to this article

References