Experimental techniques for investigating lubricated, compliant contacts

The study of Tribology between soft or compliant surfaces is not well understood despite its importance to many biological and engineering applications, ranging from synovial joints to rubber o-ring seals. It has also been shown that the science of Tribology and lubrication in compliant contacts is an important factor in the sensory perception and functionality of skin, hair and the oral cavity, and so has an immediate application of the design of consumer products such as skin creams, hair conditioners and foodstuffs. This thesis aims to improve our understanding of thin film lubrication between soft, deformable surfaces under light loading and low-pressure conditions. The primary focus of the thesis is the development of techniques by which to measure the film thickness between compliant surfaces, from the nano- to the micro-scale. Several experimental techniques currently exist for measuring film thickness in hard, metallic contacts and these are widely employed in Tribology research of engineering systems. However they require considerable modification to be applicable to compliant contacts. This thesis describes the development of two such techniques; · a optical interferometric technique; for measuring nano-scale thicknesses in compliant contacts; · a laser induced fluorescence technique; developed to enable measurement of lubricant thickness of relatively thick films in compliant contacts

Juncker’s false hope: a public investment plan without public investment

Martin Myant of the ETUI argues that the European ‘investment plan’ unveiled in late November by Jean-Claude Juncker falls far short of what is needed to get Europe growing again

When will Europe recover?

The European Union has performed exceptionally badly in economic terms in comparison with the world as a whole since 2008. The ETUI’s publication Benchmarking Working Europe 2014 poses the question of whether we are not half way through a wasted decade. The first half has been lost already and current policies promise little more than slow growth over the next few years

Upwards convergence: why wage growth should be a priority for central and eastern Europe

Wages vary significantly across European countries, but would increasing wages to create more convergence in pay levels have a damaging impact on competitiveness? Drawing on the examples of the Czech Republic, Germany and Romania, Martin Myant argues that there is scope for raising wages in central and eastern European countries to draw closer to western European levels without generating negative economic side-effects

Why internal devaluation fails

Martin Myant of the European Trade Union Institute presents evidence from a new book analysing national responses to the eurozone crisis which shows that the European Commission’s gauge of competitiveness – Unit Labour Costs – was the wrong measure and contributed to disastrous policies which deepened the recession. The solution, he says, is to focus on improving competitiveness by rising up the value chain, which requires investment in infrastructure, education, training and researc

Did the Troika get it right?

Martin Myant of the European Trade Union Institute (ETUI) examines the forecasting record of the European Commission and finds it wantin

Inlet protein aggregation: a new mechanism for lubricating film formation with model synovial fluids.

This paper reports a fundamental study of lubricant film formation with model synovial fluid components (proteins) and bovine serum (BS). The objective was to investigate the role of proteins in the lubrication process. Film thickness was measured by optical interferometry in a ball-on-disc device (mean speed range of 2-60 mm/s). A commercial cobalt-chromium (CoCrMo) metal femoral head was used as the stationary component. The results for BS showed complex time-dependent behaviour, which was not representative of a simple fluid. After a few minutes sliding BS formed a thin adherent film of 10-20 nm, which was attributed to protein absorbance at the surface. This layer was augmented by a hydrodynamic film, which often increased at slow speeds. At the end of the test deposited surface layers of 20-50 nm were measured. Imaging of the contact showed that at slow speeds an apparent 'phase boundary' formed in the inlet just in front of the Hertzian zone. This was associated with the formation of a reservoir of high-viscosity material that periodically moved through the contact forming a much thicker film. The study shows that proteins play an important role in the film-forming process and current lubrication models do not capture these mechanisms

The results of Italy’s 2012 labour-market reforms – no solution to unemployment

Gabriele Piazza and Martin Myant of the European Trade Union Institute criticise recent labour market reforms in Italy which aim to tackle unemployment by cutting protection for workers on permanent contracts. There is no evidence that this works, and Italy would be better off addressing structural problems in the Italian econom