DEPOSITION OF TIB2 AT LOW-TEMPERATURE WITH LOW RESIDUAL-STRESS BY A VACUUM-ARC PLASMA SOURCE

Titanium diboride is a very hard, abrasion resistant material that has been identified as having value as a potential erosion resistant mate rial to coat turbine components. It is desired to deposit this coating on materials that, for varying reasons, are adversely affected by the temperatures at which standard physical vapor deposition processes op erate. Deposition at lower temperatures in such processes yields a coa ting with high residual compressive stress. In the present work, titan ium diboride has been deposited on various substrate materials by cath odic arc. A technique has been developed, using pulsed high voltage bi as applied to the target, that reduces the compressive stress in the c oating, even when the coating is deposited at near room temperatures. This pulsed-bias method makes it possible to deposit TiB2 to a thickne ss of more than 10 mum at near room temperature, making the process su itable for deposition onto temperature sensitive materials.