TY  - JOUR
T1  - The Formation of Hexagonal Boron Nitride on the Surface of Stainless  Steel by Chemical Vapour Deposition
AU - , R. Louahdi AU - , V. Hays AU - , R. Le Gall AU - , S. Abdeslam 
JO  - Journal of Engineering and Applied Sciences
VL  - 2
IS  - 6
SP  - 1090
EP  - 1096
PY  - 2007
DA  - 2001/08/19
SN  - 1816-949x
DO  - jeasci.2007.1090.1096
UR  - https://makhillpublications.co/view-article.php?doi=jeasci.2007.1090.1096
KW  - Boron
KW  -nitride
KW  -stainless
KW  -steel
KW  -CVD
KW  -AES
KW  -SEM
KW  -EDX
AB  - Boron was deposited on stainless steel by Chemical Vapor Deposition (CVD) from a gaseous mixture of B<SUB>2</SUB>H<SUB>6</SUB> (diborane) with a mixture of argon and hydrogen. The SEM and EDX studies showed that an amorphous uniform layer of boron was obtained Thickness measurements were carried out using a Dektak profilometer. A minimum thickness of 2200 &Aring; was obtained.The boron enriched steel was annealed at 1050&deg;C and then quenched in water in order to avoid any precipitation (especially that of BN). Isothermal anneals were then carried out and Auger Electron Spectroscopy (AES) was used to study surface precipitation. The studies on the material isothermally annealed at 750&deg;C indicated that precipitation of hexagonal Boron Nitride (hBN) took place on the surface of the stainless steel. This precipitation is not observed if the annealing temperature is greater or equal to 800&deg;C. From the obtained data, a three-stage mechanism of BN precipitation on the surface of stainless steel was put forward. A precursion stage during which nitrogen and chromium atoms co-segregate to the steel surface. Then, superficial nitrogen atoms react with those of boron which migrate by diffusion, to form hBN. Finally, the hBN compound thus formed grows layer by layer starting from the interface.
ER  -