Articles with patterned coatings
Embodiments of an article including a substrate and a patterned coating are provided. In one or more embodiments, when a strain is applied to the article, the article exhibits a failure strain of 0.5% or greater. Patterned coating may include a particulate coating or may include a discontinuous coating. The patterned coating of some embodiments may cover about 20% to about 75% of the surface area of the substrate. Methods for forming such articles are also provided.
1. An article comprising:
a substrate including a surface;
a patterned coating disposed on the surface forming a coated surface,
wherein, when a strain is applied to the article, the article exhibits a failure strain of 0.5% or greater,
wherein the patterned coating comprises a bimodal distribution of coating thickness, the bimodal distribution comprising a lower-mode thickness in the range from 10 nm to 90 nm, and a higher-mode thickness in the range from about 50 to about 5000 nm, and
wherein the substrate surface has a surface area and the patterned coating covers at least about 20% of the surface area.
2. The article of claim 1 , wherein, when a strain is applied to the article, the patterned coating has a first region and a second region, and wherein the first region comprises a first tensile stress and the second region comprises a second tensile stress greater than the first tensile stress.
3. The article of claim 1 , wherein, when a strain is applied to the article, the substrate comprises a maximum substrate tensile stress and the patterned coating has at least one local region comprising a local tensile stress that is less than the maximum substrate tensile stress.
4. The article of claim 1 , wherein, when a strain is applied to the article, the substrate comprises a maximum substrate tensile strain and the patterned coating has at least one local region comprising a local tensile strain that is less than the maximum substrate tensile strain.
5. The article of claim 1 , wherein the patterned coating comprises a bimodal distribution of coating thickness, the bimodal distribution comprising a lower-mode thickness comprising a full-width-at half-maximum (FWHM) of about 1 nm or less and a higher-mode thickness comprising a FWHM greater than the FWHM of the lower-mode thickness.
6. The article of claim 5 , wherein the FWHM of the higher-mode thickness is less than the difference in the surface topographical heights of the lower-mode thickness and the higher-mode thickness.
7. The article of claim 6 , wherein the patterned coating comprises a plurality of peaks and a plurality of valleys between the peaks.
8. The article of claim 7 , wherein the patterned coating at the plurality of valleys comprises a coating thickness of at least about 5 nm.
9. The article of claim 1 , wherein the substrate exhibits an average strain-to-failure that is greater than an amount selected from 0.7%, 1.0%, 1.5%, 2%, 2.5% and 3%.
10. The article of claim 1 , wherein the patterned coating comprises a hardness of 8 GPa or greater, as measured by a Berkovich Indenter Hardness Test along indentation depths of about 100 nm or greater.
11. A consumer electronic device comprising:
a substrate including a surface;
a patterned coating disposed on the surface,
wherein, when a strain is applied to the article, the crack onset strain of the patterned coating is greater than 0.5%,
wherein the patterned coating comprises a bimodal distribution of coating thickness, the bimodal distribution comprising a lower-mode thickness comprising a full-width-at half-maximum (FWHM) of about 1 nm or greater, and a higher-mode thickness comprising a FWHM greater than the FWHM of the lower-mode thickness, and
wherein the substrate surface has a surface area and the patterned coating covers at least about 20% of the surface area.
12. The consumer electronic device of claim 11 , wherein the patterned coating comprises a hardness of 8 GPa or greater, as measured by a Berkovich Indenter Hardness Test along indentation depths of about 100 nm or greater.
13. The consumer electronic device of claim 11 , wherein the FWHM of the higher-mode thickness is at most two times the difference in the surface topographical heights of the lower-mode thickness and the higher-mode thickness.
14. The consumer electronic device of claim 11 , wherein the patterned coating comprises a plurality of peaks and a plurality of valleys between the peaks.
15. The consumer electronic device of claim 11 , wherein the patterned coating comprises a bimodal distribution of coating thickness, the bimodal distribution comprising a lower-mode thickness in the range from about 0 to about 100 nm, and a higher-mode thickness in the range from about 200 to about 5000 nm.