The Tribodiagnostics of the Technical Condition of the Helicopter Main Reduction Gear

This work is about the possibility of early diagnostics of the technical condition of the main reduction gear in the helicopter. Tribological tests of oil samples taken when testing the operational life are conducted based on the analytical ferrography, morphological analysis, wear particle count, and spectroscopic analysis.

Tribological Properties of (EN AW-AlCu4MgSi(A)) Aluminium Alloy Surface Layer After Ball Burnishing

EN AW-AlCu4MgSi(A) aluminium alloy is widely used as a structural material in aerospace and automotive applications. We have subjected it to grinding, polishing and ball burnishing. We have performed ball-on-disk tribological tests. We have also determined normalized 3D roughness parameters. High surface smoothness turns out to be obtainable. Favorable effect of the ball burnishing on the tribological properties of the alloy are seen. Results will be presented at the Conference.

Surface Integrity Achieved by Finishing Processes on Sverker 21 and Vanadis 6 Cold Working Tool Steels

Control of surface integrity is an important factor for components like cold working tools exposed to wear and fatigue damage. We have performed a number of operations on Sverker 21 and Vanadis 6 steel surfaces: turned + burnished, turned + nitrided and turned + burnished + nitrided. The effects were followed by surface roughness and microstructure analysis, ball-on-disc tribology and impact testing. The sequence of turned + burnished + nitrided treatments has the most favorable effect on the surface integrity of the finished tools and their industrial performance. Results will be presented at the Conference.

BASE OILS BASES SYNTHESIZED USING TECHNOLOGIES OF RECYCLING WASTE PRODUCTS OF THERMOPLASTICS

We offer the technology of synthesis of the basic foundations of lubricants from natural raw materials – animal and vegetable fats. The relevance and novelty of the research is to use the technology of recycling polymer waste. This allows adjusting the rheological, physical, mechanical properties of lubricants. We propose a method to estimating the propensity to oxidation of natural fats based rheometric measurements. We studied the efficiency of the various classes of industrial antioxidants.

Evaluation of Corrosiveness of Alkoxymethylimidazolium Ionic Liquids

In this article, the results of research works on the corrosiveness of selected ionic liquids (ILs – Ionic Liquids), based on imidazolium, are presented. The research was carried out within the framework of PBR/15-249/2007/WAT-OR00002904 Research Project financed by the Ministry of Science and Higher Education, during 2007-2011 [1]. Literature information about corrosiveness of ionic liquids to metal is very skimpy. During testing a numer of ionic liquids in terms of their implementation as lubricants for tribological nodes, it was necessary, first of all, to check their corrosiveness to metals. In this article the results of alkoxymethylimidazolium ionic liquids corrosiveness to ŁH15 steel (100Cr6, AISI 52100) and M1E copper will be presented.

Optical Interferometry Measurement of BSA Adsorption in Hydrodynamic Lubrication

The formation of adsorption layer of BSA aqueous solution under hydrodynamic lubrication conditions was studied using optical interferometry. The adsorption film was analysed and found consisting of two types of adsorption. A two-media approach was derived to determine the adsorption film thickness in real time.

Tribological Behaviour of Co-W Under Dry and Lubricanting Conditions

The dry and lubricating wear was investigated for steel and Co-W samples in the view of revealing the best performance of tungsten alloys. The tribological behaviour was studied under bi-directional ball-on-flat sliding tests: 10 N and 50 000 cycles. The given research identified that Co-W coatings have superior wear resistance than those of uncoated samples (steel ST3) under dry and also under lubricating conditions. Thus, wear volume of Co-W samples is decreasing two times under dry conditions and ten times under lubricating conditions. The use of new type of solid lubricant (sugar film) is discussed.

Tribological and Corrosion Properties of Iron-Based Alloys

Corrosion is responsible for industrial maintenance and industrial accidents costs. A helpful way to prevent corrosion is to develop advanced materials with highly anti-corrosive properties. The electrodeposition is one of the most attractive methods for obtaining these materials. This work deals with evaluation of the tribological and corrosion behaviour of electrodeposited Fe-W and Fe-W-P alloys. Electrodeposits were obtained from 4 different baths and were characterized by means of scanning electron microscopy; X-ray dispersive energy spectroscopy; X-ray diffraction spectroscopy. The hardness was determined by Micro-indentation carried out at normal forces varying from 98 mN up to 980 mN with a loading rate of 1961 mN/min. A ball-disc tribometer was used to study the tribological properties at 90 °C. A diamond indenter, having a radius of 100 µm, was used to carry the scratch test. Corrosion behaviour was studied using polarization and electrochemical impedance spectroscopy technique. It was investigated that in all cases Fe-W and Fe-W-P alloy coatings exhibit greater micro-hardness than the stainless steel substrate. The amorphous-like ternary Fe-W-P alloy coatings demonstrate higher wear and corrosion resistance and lower friction coefficient compared to binary Fe-W alloy coating.

Comparison of Ductile Damage Models During Scratch Tests - A Numerical Study

The ‘wear mode diagram’ has been commonly used to classify the deformation regime of the soft work-piece during scratching, into three modes: ploughing, wedge formation and cutting. The scratch test is used to evaluate wear modes and material removal associated with wear. There are different damage models in the literature used for the description of material behaviour after damage initiation under different loading conditions. However, there has been little analysis to compare damage models during scratch test conditions. The first aim of this work is first to use a finite element modelling package (Abaqus/Explicit) to build a 3D model to capture deformation modes during scratching with indenters with different attack angles. Three different damage models are incorporated into the model and patterns of damage initiation and propagation are compared with experimental results from the literature. This work highlights the role of the damage model in accurately capturing wear modes and material removal during two body sliding interactions.

Particularities of the Pseudo-Plastic Lubrication, with Application to the Sinovial Liquid

The present paper proposes a new model for lubrication of the hip joint with hyaluronan solutions, considering the squeeze film process of non-Newtonian fluid between rigid spherical surfaces. The heological model that approximately describes the behaviour of the synovial fluid is the power law model. For the considered case, the pressure distribution, the load capacity, the film thickness and the friction coefficient have been determinated. The conclusions of the paper offer an explication to the development of the osteoarthritis and to the problems of the arthritic patients.