Publicou 4 edições por ano
ISSN Imprimir: 1093-3611
ISSN On-line: 1940-4360
Indexed in
HETEROGENEITY OF TEXTURES AND STRESSES IN A LARGE TUNGSTEN PVD FILM
RESUMO
This study deals with texture and stresses evaluations on tungsten coating on a large steel plate (150*240 mm2), as a function of its position with the magnetron target.
The films obtained by Physical Vapour Deposition process often reveal a fiber texture, implying a residual stress determination impossible by the usual X-rays diffraction method. The beam curvature technique is also difficult to apply in the case of thick substrates, justifying our interest of the x-rays diffraction methods. The stress determination method is then the Ideal Directions Method.
· About the heterogeneity all over the film, at the coating surface, an almost perfect <111> fiber texture with slight reinforcements and a very high compressive (around -3000 MPa) and almost isotropic stress level are observed. The fiber texture presents a progressive W inclination in connection with the columnar morphology, according to the short and long target axis; this inclination is in relation with ion incidence direction. About stresses, they are rather homogeneous all over the surface with a small decrease.
· About the heterogeneity within the thickness, the <111> fiber texture transforms towards a (110) <110> texture toward the interface and a slight stress gradient is observed.