The early stage sliding contact fatigue behavior of nanocrystalline materials, with average and total range of grain sizes well below 100 nm, was studied. The evolution of friction and damage during repeated sliding contact in the nanocrystalline metals and alloys was systematically compared and contrasted with that in ultrafine-crystalline and microcrystalline materials so as to develop a broa...

In the Chemical Mechanical Polishing (CMP) process used for microelectronics manufacturing, three contact regimes between the wafer surface and the polishing pad may be proposed: direct contact, mixed or partial contact, and hydroplaning. An effective in-situ method for characterizing the wafer/pad contact and a systematic way of relating contact conditions to the process parameters are both la...

The microstructure and residual stresses of an AA6040 Al to AZ31B Mg friction stir weld are studied using scanning electron microscopy and X-ray diffraction. The complex material flow promoted by the friction stir welding process results in a fine grained structure in the stir zone of both materials due to dynamic/recovery recrystallization. The interface between the materials is characterized ...

techniques such as SEM, TGA, XRD, friction and wear tests are used to characterize the formulations as well as the commercial material. Out of the 30 formulations made, two formulations viz., S1 and S2 closer to commercial material are presented in this work. Formulation S2 exhibits better thermal stability and better wear resistance. With the help of SEM analysis, physical properties and XRD s...

In the present study, friction spot welding or refill friction stir spot welding was performed to consolidate dissimilar AA5754 Al and AZ31 Mg alloys. The intermetallic compounds of Al12Mg17 and Al3Mg2 were primarily found in the weld, distributed at the interface between the base materials and in the Al top sheet. The distribution of the intermetallic compounds and the interfacial area between...

* IDMEC, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal ** DEQ/ICEMS, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049001 Lisboa, Portugal. *** Department of Engineering Design and Production, School of Engineering, Aalto University, P.O. Box 1420, FI-00076 Aalto, Finland **** Faculdade de Engenharia da universidade do P...

The aim of this work was to characterize the initial wear kinetics of two different types of glass ionomer cement used in dentistry (the conventional glass ionomer cement and the resin-modified glass ionomer cement) under sliding friction after 28-day storing in distilled water or Ringer's solution. Sliding friction was applied through a pin-on-disk tribometer, in sphere-on-plane contact condit...

Friction and wear are part and parcel of all walks of life, and for interfaces that are in close or near contact, tribology and mechanics are supremely important. They can critically influence the efficient functioning of devices and components. Nanoscale friction force follows a complex nonlinear dependence on multiple, often interdependent, interfacial and material properties. Various studies...

Understanding friction between material pairs is very crucial when utilizing the materials in various applications, including mechanical and biological systems. In the present investigation, efforts were made to study the influence of surface texture and roughness on friction and transfer film formation during sliding of Ultra High Molecular Weight Polyethylene (UHMWPE) pins against steel plate...