WCCOCR coating with plasma

[srihan_1]

dear members
we are coated tungsten carbide cobalt chrome with plasma but in the coating we have observed so much of porosity and low hardness (50Rcmax) simultaneously we have coated with hvof also in this process there is no porosity hardness we have not checked i think it will give better hardness.
can any body tell the plasma parameters for wccocr. we are not found the plasma parameter for this coating. please suggest me.

[Gordon]

Hi srihan_1

We would require more information on equipment, powders and parameters used to be able to help.

"low hardness (50Rcmax)" Sorry, to me this is pretty much meaningless as you should not test a WC/CoCr coating using Rockwell C. If it is converted from another hardness test, again it is not very useful without knowledge of details of original test and conversion formula/tables used.

[loriolo]

Powder selection and spray process are important for Wc/Co/Cr applications in order to have a specific surface finish requirements and technological issues as porosity, higher quality coating are generally achieved using HVOF process, some time it’s possible to obtain an acceptable quality coating using high energy plasma With Ar/He plasma gas and supersonic nozzle, there is some materials with low Wc and Co/Ni, performed to use with plasma spray with self-fusing proprieties.