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Friction and wear of thin layers for MEMS

WHY

Evaluating frictional and wear characteristics of very thin nanostructured layers with macro scale tribometers, in the Newton load range, can create unrealistic conditions.  Wear phenomena are highly dependent on the contact conditions: such high loads are not relevant in the case of MEMS. The adhesive and capillary components that contribute to friction, in a micro-contact, can not be simulated with high load devices.  Therefore, there is an increasing need to use new tribological testers and procedures to obtain a better understanding of surface interactions on an appropriate scale.

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Parallel wear tests to evaluate wear in joint reconstruction - TRL6

WHY

The failure of the hip replacement is often a combination of tribocorrosion of the hip joint materials and inflammations due to wear particles in the body. A new methodology needs to be developed so as to allow for a fast prescreening of the reliability of new biomaterials, in conditions that simulate the actual conditions (e.g. environment, motion, contact pressure, countermaterial). 

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  638 Hits

Tackiness of industrial greases: a quantitative method

WHY

Lubricating greases are used in various industrial fields ranging from food, transportation, aeronautical, construction, mining and steel industry. The aim is to decrease frictional forces and to protect industrial components from wear and/or corrosion damage. Their performance depends on interaction properties like adherence to the substrate, cohesion or consistency, and tackiness. However, up to date there is no established quantitative methodology that can be easily applied to efficiently and accurately evaluate the adhesion and tackiness of a grease.

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  673 Hits

Seizure or galling resistance of materials at high speeds

WHY

In reality, due to a misalignment, vibrations or other reasons high speed pump rotors can come in contact with the stator, leading to a catastrophic failure.  This failure is a result of severe shearing of the contacting surfaces. However, the existing ASTM Galling method (G 196), is performed at very high pressures and very low speeds, and does not simulate the “actual” conditions met at high speeds.

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Measuring the friction of surgical sutures

WHY

Surgical suture, holding body tissue together after an injury or surgery, is a complex product.  The thread can be surface treated or coated for a number of reasons. One of them is to facilitate the insertion through tissue, the other to hold the knots tightly.  Friction of the suture over skin, is thus important to control.  Measuring skin-suture friction allows improvement of these threads and their surface treatment.

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  519 Hits

Abrasion by powders during powder processing

WHY

One issue in the pharmaceutical industry, is the abrasion of processing components for pressing the powders. The intensity of the abrasion phenomena strongly depends on the composition and size of the processed powders. Up to date there is no fixed procedure on how to evaluate such abrasion phenomena, in conditions that simulate the realistic process.

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  695 Hits

How can we measure the friction and wear of wires in sliding contacts?

WHY

In everyday life we come across and use applications were wires are operated in sliding contacts. Some examples are elevators, car doors, canopies etc. In the majority of these applications, friction is critical (e.g. the wire in a canopy should slide smoothly), and after a period of tuse, wear damage of the wire can also obstruct the performance.    

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  862 Hits

How to measure the friction and adhesion of skin creams

WHY

Skin creams are commonly used to improve skin health and create a smooth, soft, and moist perception. This is achieved by altering the surface roughness, friction, and adhesion of skin surface. Despite the fact that there are many commercial creams available, there is no consistent scientific approach to determine their frictional and adhesive properties.

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  1071 Hits

Pre-screening the tribological properties of shock absorbers

WHY

Shock absorber component testing is expensive and time-consuming and this is a limiting factor in developing new materials for this application. There is a need to develop a pre-screening method to get a quick but accurate evaluation of the tribological behavior of materials, without losing too much correlation with the actual conditions (geometry, wear mechanism, load, speed, number of cycles etc.).

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  734 Hits