BLOG

Search

How hard is a ceramic coating? What is 9H, 10H? Am I being fooled? – find out for yourself.

Updated: Mar 11, 2020



DETAILING, SCIENCE EXPLAINED

How Hard is a ceramic coating? What is 9H, 10H? Am I being fooled? - find out for yourself

POSTED ON MAY 28, 2019 BY PHILIP COETZEE



This is a very touchy subject as many companies have built their brand around the hardness rating. (So and so’s) 9H Ceramic.


Let’s start with a little background on both pencil hardness and the infamous MOHS scale. The pencil hardness method was originally developed by pencil manufacturers as a quality control method in the early 1900’s, if two different pencils cause the same scratch damage to a coating then they are considered the same hardness, simple. The coatings industry adopted this in a reverse manner and starting using variations of standardized pencil hardness to measure their coating hardness.


An example of a pencil hardness tester according to ASTM D33359


Fast forward to the modern day and it has become an important, yet misleading, marketing tool for companies that supply vehicle protection coatings, i.e. “Ceramic” and “Glass” and other “Nano coatings”. Ever wondered why a supposedly 9H coating can be scratched with just a fingernail?