The justification behind using Cobalt Chromium Alloy 12 […]
The justification behind using Cobalt Chromium Alloy 12 in engineering industry is to provide a corrosion-resistant and wear-resistant surface which will help combat the wear and corrosion of mechanical components. However, wear-resistant materials having a uniformly distributed, dense carbide matrix are naturally difficult to machine due to their high carbide content. In some cases, non-homogeneous hard carbide distribution, lower heat conductivity, and high hardness contribute to poor machinability for these materials.
Cobalt-based alloys are sometimes non-magnetic, but high-strength materials. These alloys are renowned for their high wear, corrosion and heat resistance properties, possess high hardness but are ductile enough materials.
These alloys nicely preserve their strength even at high temperatures for longer periods of time and they behave perfectly in corrosive and acidic environments. As mentioned earlier, cobalt-based alloys exhibit excellent resistance to degradation in the environment of human body fluid, which has led to their successful application in medical surgery and surgical implants. Several medical tests have proven [1, 3, 9] that cobalt-based alloys are biocompatible and suitable for use as surgical implants and bone replacements. According to their applications, the conventional Co-alloys may be categorized as follows:
By virtue of its excellent wear resistance and toughness Cobalt Chromium Alloy 6 has been widely used in the manufacturing of cutting bits for deep drilling equipment for mining purposes, rock crushing rollers, cement and steel equipment, and conveyor systems, steam-turbine erosion shields, half sleeves and bushings where lubrication is inaccessible or effective lubrication is impossible. Another alloy, Cobalt Chromium Alloy 3, containing 3 times as much tungsten (W) as Cobalt Chromium Alloy 6, 6B, and 6K, and having no Mo is inferior to Cobalt Chromium Alloy 6, 6B and 6K in corrosive environments and is not recommended for uses in such situations.
Cobalt Chromium Alloy are highly useful and popular representatives of Cobalt Chromium Alloy groups. By virtue of their above mentioned superior mechanical properties cobalt chromium alloy have, as mentioned earlier, applications in many industries such as oil and gas, automotive, aerospace, pulp and paper, food processing, wood and timber, nuclear industries and in medical surgery for producing surgical tools and human bone/part replacements.