2012-10-23 Surface coating

Cladding of Large Components: Comparing Conventional and New Technologies and Materials

The performance of conventional cladding techniques, on the coating of large industrial compponents, is analyzed and compared against a high end technique. A variety of criteria are used such as mechanical, metallographic and economic in order to obtain a more complete picture. The conventional technique under investigation is Gas Metal Arc Welding (GMAW/MIG) being one of the most established in the field, while the high end counterpart is an emerging technique referred to as Laser Cladding. The mechanical performance is judged in regard to tensile testing with marine classification society rules in mind. Furthermore, the economic aspects of the operation are examined considering capital investment, labour, welding consumable as well as post welding operation costs. A cladding material often used in such applications is compared, an austenitic stainless steel AISI 316L. In the case of the conventional tecnique, the filler material is in wire form while in the case of the laser technique, metal powder is used. Results indicate that the laser technique presents significant advantages in all respects as faster turnaround can be achieved with less material consumed and lower labour cost. While equivalent if not better mechanical and corrosion properties can be realised.