Rtec-instruments tribometer

Rtec-instruments launched a new versatile next generation Tribometer. The multi functional tribometer goes from mN to 5000N, -150 to 1500C, can run several ASTM/DIN /ISO standards on same platform. For comprehensive characterization tester comes with several optional add ons such as white light interferometer, AFM, raman spectrometer etc.

http://rtec-instruments.com/multi-functional-tribometer.htm

Sunscreen tester

Testing Lotion on Finger

The FDA just announced Tuesday that sunscreen products will be labeled with information that not only help prevent sunburn but help consumers identify products that can reduce the risk of skin cancer and early skin aging as well.


To develop a successful consumer products such as Sunscreen, it not only involves health related issues but also involves end user comfort and perception (ofcourse marketing). 






These tests can be done on real human arm/finger or on artifitical skin, hair etc.

Nanoscratch tester for pain killer delivery

I was a part of very exciting test last week. The test involved testing coatings on injectors/piston of a small pump, which will sit INSIDE human body (like artificial heart) to inject pain killers at the right spot everyday automatically. They are specifically being used to ease acute back pain. Just imagine the benefits, no more back pain or eating tablets. The pump would dose couple of ppm of  pain killer on the particular area once a day/week etc.

On down side, if the pump fails you can imagine the disasters.

For this test we used a nanoscratch tester to measure scratch hardness, wear, durability, hardness and modulus of coatings. All the tests were done on same tool. Scratch test using nanoscratch head, hardness using easy to interchange nano indentation head, wear and durability using nanotribology head.

Scratch test on Window Glass

Did you know a normal window glass at our home , office, car etc has atleast 10 coatings on top of glass. To protect against UV, sunlight, wear, scratch etc. I was surprised to hear how much work goes behind making a simple breakable window glass.

I learnt this from a company, which plans to make DIRT/water/steam resistant coating.  The treated window will shine for atleast 5 years, without cleaning. (too bad for people who clean window panes :D).

We did nano scratch and nano wear test on those glass panes to find scratch hardness, wear rate, life , durability of those coatings (typically 10-50nm thick). I will try to post data and pictures soon. Acoustic emmision (noise signal) was very helpful in detecting crack propogation on these coatings. 

PS I would love to get one of these in my bathroom (no fog on mirror)..

Tribo corrosion tester and SMT23 conference

I just returned from smt23 conference in India. This was a thin film and coating conference. The conference was well organised. (Its interesting, we get nothing to eat at american conferences, some food at European conference and alot of food at asian conferences).

I was amazed to see how many people wanted to do tribo-corrosion studies on there coatings.  My  lecture was well received and the booth was full of people.

A brief summary of the word i repeated atleast 100 times at conference.

Tribo Corrosion tester - we have  tribometers which can do insitu corrosion studies. It has a powerful potentiostat attached, couple of pH probes and advanced sensors that will let you study tribology and corrosion at same time. The drive holding the electrolyte can be spun at high velocity (we have both dynamic and passive electrolyte recirculation options.)

Guidewire test

Guidewires are inserted in a patient to the spot where a catheter or other tube must go. The medical tube is then inserted over the guidewire. Coatings increase lubricity, reduce the risk of infection or add other desired characteristics

Following tests were done to characterize Guidewires .

(i) Friction Test: The test performed with wire-on-wire (cross cylinder mode) Two pieces of the same test specimen was used. One piece was be placed over the other at 90 degree angle, and moved over each other in reciprocating mode with low controlled  load to obtain coefficients of friction (COF).

(ii) Wear Durability Test: This test  used similar cross cylinder schematic as the friction test above.   COF, electrical resistance and the time of coating failure of all samples was recorded.  

(iii) Scratch Adhesion Test: The test consists of scratching the coating with a flat side of WC microblade with a linearly increasing load over known distance. Friction force (Fx), normal force (Fz) and electrical resistance data was recorded to obtain the scratch adhesion property of coated wires at the load at which electrical resistance and COF exhibit a sudden change of all  samples.   

(iv) Hardness Test: Hardness 

The data was very interesting and conclusive. It took us a week to get the above mentioned tests done. The biggest issue was to mount these guide wires (our one engineer figured out a smart way)

Stent

My next bog will cover tribological and mechanical aspects of heart stents.. Here is the basic intro from american heart.org page.


What is a stent and how is one used?

A stent is a wire metal mesh tube used to prop open an artery during angioplasty. The stent is collapsed to a small diameter and put over a balloon catheter. It's then moved into the area of the blockage. When the balloon is inflated, the stent expands, locks in place and forms a scaffold. This holds the artery open. The stent stays in the artery permanently, holds it open, improves blood flow to the heart muscle and relieves symptoms (usually chest pain). Within a few weeks of the time the stent was placed, the inside lining of the artery (the endothelium) grows over the metal surface of the stent.