The present paper reports on a comparative study of the microstructure, hardness and cavitation erosion behaviour of Ti–6Al–4V laser nitrided under different gas atmospheres with nitrogen concentrations of 0–25%. By varying the nitrogen content of the gas atmosphere, the structure and hence the hardness and cavitation erosion behaviour of the laser nitrided layers can be controlled in a wide range. With increasing nitrogen content of the gas atmosphere, the structure within the laser nitrided layers characteristically changed from martensitic α′-Ti to a fine mixture of α- and β-Ti grains, finally leading to the formation of different titanium nitrides. The study revealed that the increase of hardness and cavitation erosion resistance can be mainly attributed to solid solution hardening of the nitrogen. It is shown that optimum cavitation erosion resistance is only achieved if crack free layers containing no brittle titanium nitrides are produced.
MortonP. H. and BellT.: Proc 6th World Conf. on ‘Titanium’, (ed. LacombeP.et al), les editions de physique, 1705–1712; Canne, France, June1988, Société Francaise de Métallurgie.
2.
BloyceA., DongH. and HansonB.: Proc. 8th World Conf. on ‘Titanium’, (ed. BlenkinsopP. A.et al), 1975–1982; Birmingham, UK, October1995, London, The Institute of Materials.
3.
DongH. and BellT.: Proc. 10th World Conf. on ‘Titanium’, (ed. LiitjeringG. and AlbrechtJ.), 867–874; Hamburg, Germany, July2003, DGM/Wiley-VCH Verlag GmbH & Co. KGaA.
4.
WalkerA., FolkesJ., SteenW. M. and WestD. R. F.: Surf Eng., 1985, 1, 23–29.
5.
BergmannH. W.: Z. Werkstofftech., 1985, 16, 392–405.
6.
BellT., BergmannH. W., LanaganJ., MortonP. H. and StainesA. M.: Surf Eng., 1986, 2, 133–143.
7.
MassoudJ. P. and CoquerelleG.: Proc. 6th World Conf. on ‘Titanium’, (ed. LacombeP.et at), les editions de physique, 1847–1852; Canne, France, June1988, Société Francaise de Métallurgie.
8.
XinH. and BakerT. N.: Proc. 8th World Conf. on ‘Titanium’, (ed. BlenkinsopP. A.et al), 2031–2038; Birmingham, UK, October1995, London, The Institute of Materials.
9.
WeisheitA. and MordikeB. L.: Surf Eng., 1995, 11, 160–161.
10.
RobinsonJ. M., AndersonS., KnutsenR. D. and ReedR. C.: Mater. Sci. TechnoL, 1995, 11, 611–618.
11.
RobinsonJ. M. and ReedR. C.: Wear, 1995, 186-187, 360–367.
12.
GerdesC., KarimiA. and BielerH. W.: Wear, 1995, 186-187, 368–374.
13.
de DamborenaJ., FernandezB., LopezV. and VazquesA. J.: Int. J. Mater. Prod Technot, 1996, 11, 301–309.
14.
MasseJ. E. and MathieuJ. F.: Mater. Manuf Process., 1996, 11, 207–214.
15.
HuC. and BakerT. N.: J. Mater. Set, 1997, 32, 2821–2826.
16.
MridhaS. and BakerT. N.: J. Mater. Process. TechnoL, 1998, 77, 115–121.
17.
BonbS., BrennerB. and BeyerE.: Mat.-wiss. Werkstofftech., 2001, 32, 160–165.
18.
BonbS., BrennerB., ScheibeH.-J. and BeyerE.: Proc. 10th World Conf. on ‘Titanium’, 1001–1008; Hamburg, Germany, July2003, DGM/Wiley-VCH Verlag GmbH & Co. KGaA.
19.
ManH. C., CuiZ. D., YueT. M. and ChengF. T.: Mater. Sci. Eng. A, 2003, A355, 167–173.
20.
HuC., MridhaS., UbhiH. S., HoldwayP., BowenA. W. and BakerT. N.: Proc. 8th World Conf. on ‘Titanium’, (ed. BlenkinsopP. A.et al), 1959–1966; Birmingham, UK, October1995, London, The Institute of Materials.
21.
XueL., IslamM., KoulA. K., BibbyB. and WallaceW.: Adv. Perform. Mater., 1997, 4, 389–408.
22.
HuC., XinH., WatsonL. M. and BakerT. N.: Acta Mater., 1997, 45, 4311–4322.
23.
XinH., WatsonL. M. and BakerT. N.: Acta Mater., 1998, 46, 1949–1961.
24.
XinH., HuC. and BakerN.: J. Mater. Sci., 2000, 35, 3373–3382.
25.
SelamatM. S., BakerT. N. and WatsonL. M.: J. Mater. Process. Technol., 2001, 113, 509–515.
26.
KasparJ., LuftA., BonBS. and BrennerB.: Proc. Conf. on Nitrieren, Stickstoff im Randgefuge metallischer Werkstoffe’, (ed. GroschJ. and MittermeijerE. J.), 207–216; 2002, Aachen, AWT.
27.
KasparJ., LuftA., BonBS., WinderlichB. and BrennerB.: Proc. 10th World Conf. on ‘Titanium’, (ed. LiitjeringG.et al), 949–956; Hamburg, Germany, July2003, DGM/Wiley-VCH Verlag GmbH & Co. KGaA.
28.
DraugelatesU., ReiterR. and HolzmiillerB.: Proc. Conf. on ‘Reibung und verschleiB’, (ed. zum GahrK.-H.), 197–202; 1996, Bad Nauheim, DGM Informationsges.-Verl.
29.
FuY., DuH. and GuY.: J. Mater. Eng. Perform., 2000, 9, 571–578.
