Thin-film coating pretreatment
Processing Details
- Roughening
Ti coating film formation
![Without pretreatment](/dcms_media/image/en2_18_film-coating_1.png)
![Film formed after wet blasting](/dcms_media/image/en2_18_film-coating_2.png)
What is "thin film coating pretreatment" by wet blasting?
When wet blasting is used as pretreatment for coating, a strong coating film can be formed on the surface by the anchor effect, which provides nano-level fine unevenness having no time dependency.
Wet blasting is a physical process and compatible with a wide range of organic and inorganic materials.
Four features of wet blasting
- No time dependency - There is no time dependency due to the wettability improved by surface area expansion.
- No deterioration - Since processing heat is not generated, no deformation or deterioration occurs.
- Nano anchor formation - Nano-level fine uneven surfaces are formed and an anchor effect can be expected.
- Fast batch processing - The etching rate is larger than that of other surface etching methods. The desired etching amount can be obtained in a short time.
Wet Blasting Image
Wet blasting is a technique to project a mixture of abrasive and water at high speed with compressed air against a material to clean, process, and modify its surfaces. This technique allows fine abrasives to be used due to wet processing, and is good at forming a fine uneven surface while grinding the surface of the workpiece while silmutaneously removing dirt and foreign matter.
In addition, this chemical-free technique is eco-friendly and environmentally friendly, and it is also effective in reducing industrial waste.
For further information, see also "Introduction to wet blasting.”
![ウェットブラスト 処理イメージ](/dcms_media/image/film_coating_fig1.png)
Evaluating the cleaning power of wet blasting
A comparison of untreated and wet-blasted surfaces shows that the amount of carbon (contamination) on the surface was reduced.
Comparison of element concentrations before and after wet blasting
![Comparison of element concentrations before and after wet blasting](/dcms_media/image/en2_18_film-coating_3.png)
Treatment Example
Glass x SiO2 Coating
Cross-Cut Test Results
![Without pretreatment](/dcms_media/image/en2_18_film-coating_4.jpg)
Ra 0.01 µm / RzJIS 0.14 µm
![Film formed after wet blasting](/dcms_media/image/en2_18_film-coating_5.jpg)
Ra 0.05 µm / RzJIS 0.37 µm
- Processing condition / abrasive: Polygonal alumina / Air pressure: 0.20 MPa
Processing Example
SUS×TiN Coating
Scratch Test Results
![Untreated workpiece](/dcms_media/image/en2_18_film-coating_6.jpg)
Load: approx. 4.27 N (with peeling)
![Wet blasted workpiece](/dcms_media/image/en2_18_film-coating_7.jpg)
Load: approx. 4.27 N (without peeling)
![Results of scratch test](/dcms_media/image/en2_18_film-coating_8.png)