Van der Waals force
From apm
Revision as of 17:03, 20 August 2018 by Apm (Talk | contribs) (→Comparison: elaborated - more explicit)
This page is not going to discuss the origin and nature of the VdW force but is focusing on practical applications and an intuitive understanding.
Contents
Practical usage
Comparison
(wiki-TODO: make a table comparing stiffness force and energy to a single covalent C-C bond by showing equivalent area)
Two coplanar atomically flat surfaces attract each other quite a lot.
- ~1nN per square nm this equates to around ~10,000 bar.
Original Source: (Nanosystems 9.7.1.)
indirect source: [1] (beware: the noted binding energy is mistakenly taken from a covalent interface - Nanosystems 9.7.3.)
double indirect source: [2] - ~2.7nN per square Nm 1/20 the tensile strength of diamond
Source: (Nanosystems 3.5.1.b) (more than titanium and low grade steel)
They can still slide effortlessly along each other (possibly superlubricating) so depending on the use male protrusions penetrating female indents may be needed to prevent that. (intuitive feel)
(wiki-TODO: find the missing value)
Theory
Please use external sources - there are plenty out there.
Wikipedia: [3]
