IJMC Basic Research

		      IJMC - Basic Research

You know, I just have to wonder about the experiments some of the 
scientists mentioned below used to test their theories. Anyone want to 
become a volunteer subject for the next set?			 -dave



---------- Forwarded message ----------
From: David Aronstein <daron@optics.rochester.edu>
Subject: Basic Research

If you aren't in the mood for humor best suited for a hyperactive, overly 
hormonal 12 year old...  perhaps this letter is best deleted now without 
further reading.



I'm usually a good person, but studying all day, every day, in the library 
over the last few weeks has made me a bit loopy.

I have a favorite little nook in the library, way in the back, past all 
of the shelves of scientific journals.  As I wander over to my special 
spot, I let my eyes wander over all of the journals I pass.  They have 
titles like "Journal of Physics and Chemistry of Solids" or "Wildlife 
Review" or "Selected Water Resources Abstracts" or even the "IEEE 
Transactions on Information Theory."  

Today I took a different route to my study chateau.  I passed a different 
set of bound journals, each one beckoning me with a new and exotic title.

Through the corner of my eye, I saw it.  Could it be?  Yes, yes it is.  I 
knew this was going to be an interesting experience.  There it was:

"The Journal of Lubrication Technology."

I was intrigued.
I was fascinated.
I grabbed the latest bound volume.

There were two articles in particular that really impressed me.
The first:

"Interactions Between Dynamic Normal and Frictional Forces During 
Unlubricated Sliding"

by A. Soom and C. Kim.


The first sentence says it all:

"When unlubricated surfaces slide over one another at speeds of a few 
centimeters per second or faster, the generation of audible sound usually 
accompanies the sliding process."

Moving on, I then found the Holy Grail of lubrication technology:

"Experimental Investigation of the Effect of System Rigidity on Wear and 
Friction-Induced Vibrations."

by V. Aronov, A. F. D'Souza, S. Kalpakjian, and I. Shareef.

This is full of fascinating little gems, all from the Introduction:

"Self-excited vibrations of the stick-slip type have been studied by 
several investigators in the past [1]."

"In the study of Brockley and Ko [5], as the sliding speed was increased 
further, it was observed that there exists another critical speed at 
which a different type of self-excited vibrations are induced."

"Yokoi and Nakai [6] also observed quasi-harmonic vibrations which they 
named 'squeal.'"

"Bhushan [7] employed a glass slider, sliding over a rubber stave with 
water lubrication.  He observed two types of friction-induced vibrations, 
namely, low frequency oscillations which he has named 'chatter' and high 
frequency oscillations which he has named 'squeal.'"

"Generally, squeal was generated at low normal loads and high speeds, 
whereas chatter was generated at high load and low speed or very high 
load and any speed."

and finally...

"Usually it can be expected that any type of friction induced vibrations 
will cause damage to the surface and result in excessive wear."


These papers just remind me again how basic research can prove to be 
useful in making life better for all humanity.

--david






IJMC October 1995 Archives