1. The ratio of hardness, an aluminum one is titanium, as long as the two materials with each stroke painting. Scratched one is aluminum. Because titanium hardness than aluminum.
2. The ratio of acid, aluminum case of acid from the chemical reaction immediately, good acid resistance of titanium.
3. The specific strength, hand pliers, scissors very effort damage aluminum, titanium, very laborious.
4. The ratio of color on a piece of paper draw a few scratches on the aluminum immediately left black, titanium invisible scratches.