We present a classical rolling contact apparatus where two discs roll and slide under a constant normal loading. Experimental results concerning bearing steel used in ambient air or under severe temperature conditions (Liquid Nitrogen) are presented. A simplified model proposed by Kalker (Fastsim) is used to identify the dynamic friction coefficient between these discs and to study the apparatu...

The wear of ultrahigh molecular weight polyethylene (UHMWPE) is considered as one of the major reasons for revision of artificial joints. While in vivo measurements have shown a significant temperature increase in knee implants, the amount of heat dissipated within the UHMWPE tibial component and its influence on the friction behavior when paired with a cobalt-chromium (CoCrMo) femoral componen...

The viscoelastic effect of rubber material on creation of rolling resistance is responsible for 10-33% dissipation of supplied power at the tire/road interaction surface. So, evaluating this kind of loss is very essential in any analysis concerned with energy saving. The transient dynamic analysis for including the rolling effects of the tire requires long CPU time and the obtained results are ...

The physics describing ultrasonic wire bonding is only partly known. A better understanding how bond strength depends on process parameters could increase productivity by speeding up process ramp-up and increasing process reliability. In this work, the influence of normal force and ultrasonic amplitude on the ball bond quality is investigated. The determination of the ultrasonic friction energy...

automobile body plays crucial role in preventing the collision energy transfer in severe accidents to the passengers. if the collision energy is dissipated or saved in bumper or chassis, the amount of damage to the occupants would be minimized. using novel laminated panel (fiber metal laminate) in auto body, and considering the characteristics such as high energy absorption, strength, high dent...

Torsional fretting behavior of TC4 titanium alloy has been investigated at different parameters to explore the wear resistance and mechanisms alloy. The loops, dissipated friction energy torque under normal load (100N 200N), angular displacement (±0.5° ±2°) frequency (10Hz 15Hz) were studied reveal mechanical during fretting. Results showed that made difference in while was most important facto...

in this work, homogeneous thermochemical co-precipitation method was used to fabricate w-25wt%cu nanocomposite. synthesized nanocomposite powder was calcined and reduced. a hydrogen atmosphere sintering at 1200oc for 105 consolidated the product up to a density close to 98% theoretical density. wear experiment were carried out using a pin-ondisc set up at three normal loads of 5, 10 and 15 n an...

Abstract Acoustic emission (AE) monitoring offers the potential to sense particle-scale interactions that lead macro-scale responses of granular materials; however, there remains a paucity understanding fundamental links between mechanisms and AE generation in particulate materials, which limits interpretation measured AE. The objective this study was establish particulate-scale energies activi...

Two decades ago, the literature dealing with the possible applications of low molar mass liquid crystals, also called monomer liquid crystals (MLCs), only included about 50 references. Today, thousands of papers, conference reports, books or book chapters and patents refer to the study and applications of MLCs as lubricants and lubricant additives and efforts are made to develop new commercial ...

Talar osteochondral lesions (OCL) frequently occur following injury. Surgical interventions such as femoral condyle allogeneic or autogenic osteochondral transplant (AOT) are often used to treat large talar OCL. Although AOT aims to achieve OCL repair by replacing damaged cartilage with mechanically matched cartilage, the spatially inhomogeneous material behavior of the talar dome and femoral d...