Various Grades of Cobalt Chromium Alloy III

Update:11 Jan 2019

As mentioned in the previous two articles, Cobalt Chrom […]

As mentioned in the previous two articles, Cobalt Chromium Alloy has been widely used as a special engineering material. It has excellent performance in high temperature resistance, wear resistance, cavitation resistance and corrosion resistance, but the performance of alloys of different grades is various. Some grades of alloys are designed for a specific purpose. When used, the grades must be carefully selected to achieve superior performance. Apart from the alloys mentioned above, the main properties and uses of various types of some cobalt chromium alloys are summarized as follows:

1.Cobalt Chromium Alloy SF1, SF20

The two alloys are hard-faced alloys that adopt a spray-melting process. The

hardness of the sprayed coatings is similar to the coating hardness of the Cobalt Chromium Alloy 1 and Cobalt Chromium Alloy 20 respectively. The coating HRC54 of Cobalt Chromium Alloy SF1 can be machined, but it is more difficult. With HRC>60, the coating of Cobalt Chromium Alloy SF20 can only be ground.

2.Cobalt Chromium Alloy 100

With HRC>61~66 and highest thermal hardness, cobalt chromium alloy 100 is the hardest of cobalt chromium alloy. When the temperature exceeds 800℃, HRC45 is the most abrasive wear resistance with good corrosion resistance but cannot be machined. Used as tools and milling inserts, these alloys are specifically designed for metal cutting. Nowadays, cobalt chromium alloys have been researching and developing.

As an expensive metal, cobalt is concentrated in Zaire and Zambia in Africa around the world. Meanwhile, cobalt is sensitive strategic material. Therefore, people are studying the cobalt-free cobalt chromium alloy to reduce the price, the resource constraints and artificial monopolies.

In addition, cobalt is changed from Co59 to Co60 after neutron irradiation. Co60 is a strong radioactive source with an extremely long half-life. Therefore, Co60 is a very radioactive source with a long half-time. Therefore, Cobalt Chromium Alloy 3 should be used with caution in the nuclear industry and must be away from the nuclear irradiation area to avoid contamination.