Title: Coatings for Ti6Al4V in cryogenic space engine applications

Authors: I. Lemaire-Caron, N. Isac, M. Quillien, T. Da Silva Botelho, R. Gras, T. Ganne

Addresses: Laboratoire d'Ingenierie des Structures Mecaniques et des Materiaux, EA 2336, Institut Superieur de Mecanique de Paris, 3, rue Fernand Hainaut, 93407 Saint Ouen Cedex, France. ' Laboratoire d'Ingenierie des Structures Mecaniques et des Materiaux, EA 2336, Institut Superieur de Mecanique de Paris, 3, rue Fernand Hainaut, 93407 Saint Ouen Cedex, France. ' Laboratoire d'Ingenierie des Structures Mecaniques et des Materiaux, EA 2336, Institut Superieur de Mecanique de Paris, 3, rue Fernand Hainaut, 93407 Saint Ouen Cedex, France. ' Laboratoire d'Ingenierie des Structures Mecaniques et des Materiaux, EA 2336, Institut Superieur de Mecanique de Paris, 3, rue Fernand Hainaut, 93407 Saint Ouen Cedex, France. ' Laboratoire d'Ingenierie des Structures Mecaniques et des Materiaux, EA 2336, Institut Superieur de Mecanique de Paris, 3, rue Fernand Hainaut, 93407 Saint Ouen Cedex, France. ' SNECMA – Laboratoire Materiaux et Procedes, Foret de Vernon, BP 802, 27208 Vernon Cedex, France

Abstract: Fretting damage appears in quasi-static mechanisms submitted to small amplitude oscillatory motion. Depending on the amplitude of displacement, it could lead to catastrophic failure in many industrial applications due to crack initiation or wear damage. To reduce the damage caused by fretting, an increasing use of coatings and surface treatments has been made. In service, the grooves in cryogenic (liquid hydrogen) turbopump shaft in Ti6Al4V can be damaged, a Cu-Ni-Si P.V.D. coating has solved the problem. New diamond-like-carbon (DLC) coatings with interesting tribological properties seem to be attractive for solving industrial problems. The present study analyses the behaviour of plasma nitrided Ti6Al4V with or without a DLC layer. Its effect on crack initiation resistance will be characterised for TI6Al4V substrate. The increase of load capacity due to the treatments will be evaluated in a cryogenic environment.

Keywords: fretting damage simulation; Ti6Al4V; plasma nitriding treatment; DLC coating; cryogenic environment; space engine application; modelling; crack initiation; wear damage; cryogenic turbopump shafts; liquid hydrogen; PVD coatings; diamond-like carbon; titanium alloys.

DOI: 10.1504/IJESMS.2009.031358

International Journal of Engineering Systems Modelling and Simulation, 2009 Vol.1 No.4, pp.253 - 261

Available online: 01 Feb 2010

Full-text access for editors Access for subscribers Purchase this article Comment on this article