Substrate preparation VS bonding strength

[plzc126330]

Hi All experts,


i have a question about substrate preparation and bonding strength relationship, does anyone have any data show their relationship.
eg. sand blasting with 46#WA on SS sample Ra 5, than coated with WC12Co coating 100 μm, bonding strength is around 74 MPa..........................
Thanks a lot for your any experiences data share!

[Gordon]

Hi plzc126330

First, to show a relationship between coating bond strength and substrate preparation you need a coating that fails at the substrate/coating interface. Cohesive failures within the coating and glue failures will not be useful in showing a relationship.

In my experience the tungsten carbide based coatings always remain intact after testing, only the glue fails ( ~ 95 MPa ). This includes grit blasted and smooth ss steel substrates.

[plzc126330]

Hi plzc126330

First, to show a relationship between coating bond strength and substrate preparation you need a coating that fails at the substrate/coating interface. Cohesive failures within the coating and glue failures will not be useful in showing a relationship.

In my experience the tungsten carbide based coatings always remain intact after testing, only the glue fails ( ~ 95 MPa ). This includes grit blasted and smooth ss steel substrates.

Dear Gordon,

Thanks a lot for your reply!
so there how much influence in case with sand blasting or not VS bond strength value; so for WC coating there has not different for both preparation or not?
in case ceramics coating, any relationship for both condition?
thanks a lot!