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Comment by dr prem raj pushpakaran on September 30, 2011 at 5:11am

interesting topic

Dr. Prem Raj Pushpakaran

http://myprofile.cos.com/drprpnitc http://www.thescientistforum.com/profile.php?ID=166&sh_photoMod..

http://livedna.net/?dna=91.116

http://www.incredb.org/investigator.php?incredb_id=373&next=next

Comment by NANOVEA on May 21, 2011 at 12:37am

A Superior Indenter Design: Direct Load vs. Cantilever & Lever Pivot

The Direct Loading design is just that, a direct load, providing more stability and accuracy over a longer period of time. The real power of a piezo control can be effective as the load will react at close to the same speed as the piezo. This is essential to follow quick surface events or during scratch and wear testing when this control is central to obtaining repeatable and accurate results. It is the Direct Load design that enables Nanovea to provide the widest and most accurate testing on a single Indenter module. While others claim wide testing capability and accuracy, it is doubtful that when compared their Indenter design can match that of the Nanovea Indenter Modules.

The Cantilever design (Indentation Testing) creates an indirect loading which over time weakens the flexible arms stability causing inaccurate data unless it is regularly calibrated. Furthermore, this flexibility is the reason why it is impossible for cantilever technology to attain the speed of feedback loop action-reaction of a direct loading system. 

The Lever Pivot design (Scratch Testing) creates an indirect loading on the sample under test. The additions of multiple parts compared to a direct loading system will tend to wear faster with time and is more prone to damage and more difficult to repair at often a higher cost. More importantly, the increased distance between the driving force and the Indenter slows the load control loop reaction compare to a direct loading system, for which a movement is matched right away by the indenter. This is critical during scratching as this will determine the speed at which the load can be readjusted after the surface starts cracking. This indirect loading can also create out of control oscillations when the substrate is soft such as for plastics or rubbers.

Comment by Joice Sophia on July 21, 2009 at 11:15am

Nanoindentation is a fingerprint of the mechanical property of material