Gr. 6

Grade 6 is the most common type of cobalt-based alloy, appreciated for its exceptional balance of resistance to abrasion, corrosion, erosion, and thermal shock. This alloy offers excellent resistance to adhesive wear, galling, and compression, maintaining its properties at all operating temperatures. Its structure is hypereutectic, characterized by a network of about 13% eutectic chromium carbide, finely distributed within a solid solution matrix of cobalt-chrome-tungsten. Gr. 6 is widely used for coating valve faces and seats, hot-cutting blades, punches, and dies. It is ideal for ingot tong ends and hot steel-handling equipment. In the
petrochemical industry, it is applied on gate valves for catalytic crackers. It is also used in many other sectors, including steelworks, cement plants, maritime industry, and power generation. Preheating in the range of 100-300 °C may be required, followed by slow cooling to minimize the risk of cracking, especially with multilayer deposits or under high mechanical restraint conditions. The deposits created are machinable with carbide tools and can be finely finished by grinding. These alloys do not undergo allotropic transformations, preserving their properties even after possible heat treatments on the base metal.

Cobalt based alloy composed of 27%-32% Chrome, 4%-6% Tungsten, 1%-2% Carbon, 3%-4% Nickel, 1%-2% Silicon and 3%-4% Iron.

In the as-welded condition the microstructure consists of a cobalt based austenite with a number of carbides and other complex phases.

Used for surfacing mild, low alloy and stainless steels, and also for nickel base alloys. Can also be used for the repair of UNS R30006, Stellite 6 (Deloro Stellite).