Tribological and design parameters of lubricated sliding bearings

High performance, longevity and tribological behavior of lubricated sliding bearings are in close connection with selected design and tribological parameters. Among others, the most important are load carrying capacity dimensions, clearance, material and surface properties. Selection of these parameters is discussed and some recommendations in accordance with operating conditions are shown

Tribological and design parameters of lubricated sliding bearings

High performance, longevity and tribological behavior of lubricated sliding bearings are in close connection with selected design and tribological parameters. Among others, the most important are load carrying capacity dimensions, clearance, material and surface properties. Selection of these parameters is discussed and some recommendations in accordance with operating conditions are shown

Tribological behaviour of Al-based MMCs and their application in automotive industry

The use of different kind of composite materials is in constant growing over the years, because they have better physical, mechanical and tribological properties comparing to matrix materials. Composite materials based on light metals like Aluminium, Magnesium and Zinc, due to their low density, find application in many industries. In automotive industry they are used for pistons, cylinders, engine blocks, brakes and power transfer system elements. This paper considers the tribological properties of Al-based MMCs as a function of the manufacturing technologies and variation of shape, dimension and percentage of reinforcement material

Investigation of abrasive wear resistance of ferrous-based coatings with scratch tester

Abrasive wear resistance is very important in many applications and in most cases it is directly correlated with hardness of materials. Possible solutions for overcoming poor abrasive wear resistance of light metals, like Al-alloys, is using of coatings. In this paper the investigated results of the two types of ferrous-based coatings were presented and compared with gray cast iron, known as a material with good abrasive wear resistance. Process used for coating deposition on an Al-Si alloy substrate was Atmospheric Plasma Spraying (APS). Scratch tests with diamond indenter were used to simulate abrasive wear process. The indenter velocity of 10 mm/min was used over a wear tracks of 10 mm, with different normal loads applied. Both, coefficient of friction and wear rate of the samples were investigated and analyzed in correlation with its mechanical properties.

Investigation of abrasive wear resistance of ferrous-based coatings with scratch tester

Abrasive wear resistance is very important in many applications and in most cases it is directly correlated with hardness of materials. Possible solutions for overcoming poor abrasive wear resistance of light metals, like Al-alloys, is using of coatings. In this paper the investigated results of the two types of ferrous-based coatings were presented and compared with gray cast iron, known as a material with good abrasive wear resistance. Process used for coating deposition on an Al-Si alloy substrate was Atmospheric Plasma Spraying (APS). Scratch tests with diamond indenter were used to simulate abrasive wear process. The indenter velocity of 10 mm/min was used over a wear tracks of 10 mm, with different normal loads applied. Both, coefficient of friction and wear rate of the samples were investigated and analyzed in correlation with its mechanical properties.

Tribological behaviour of Al-based MMCs and their application in automotive industry

The use of different kind of composite materials is in constant growing over the years, because they have better physical, mechanical and tribological properties comparing to matrix materials. Composite materials based on light metals like Aluminium, Magnesium and Zinc, due to their low density, find application in many industries. In automotive industry they are used for pistons, cylinders, engine blocks, brakes and power transfer system elements. This paper considers the tribological properties of Al-based MMCs as a function of the manufacturing technologies and variation of shape, dimension and percentage of reinforcement material

Tribological properties of Al-Si alloy A356 reinforced with Al2O3 particles

MMCs as new and promising materials are under constant development and their application in different industries is increasing. They have better mechanical and tribological properties comparing to the matrix materials. This paper presents tribological tests results of Al-Si alloy A356 (EN-Al Si7Mg0.3), with and without 3 wt. % Al2O3 reinforcement. The reinforcement was in the shape of particles with 12 μm in diameter and the technology for producing of composite was compo casting. The pin-on disc tribometer was used to carry out these tests under dry sliding conditions at different loads. Worn surfaces and wear debris were also observed and analyzed with scanning electron microscopy (SEM).

Tribological properties of Al-Si alloy A356 reinforced with Al2O3 particles

MMCs as new and promising materials are under constant development and their application in different industries is increasing. They have better mechanical and tribological properties comparing to the matrix materials. This paper presents tribological tests results of Al-Si alloy A356 (EN-Al Si7Mg0.3), with and without 3 wt. % Al2O3 reinforcement. The reinforcement was in the shape of particles with 12 μm in diameter and the technology for producing of composite was compo casting. The pin-on disc tribometer was used to carry out these tests under dry sliding conditions at different loads. Worn surfaces and wear debris were also observed and analyzed with scanning electron microscopy (SEM).

Ecological and technical aspects of the waste oils influence on environment

In the last ten years, the world demand for lubricants is around 36 millions tons per year. More than 50 % of that amount is lost in exploitation, and the rest is potentially collectable waste oil. Waste oils are a serious threat to the human health and especially the environment. In order to prevent this threat, a proper waste oil management should be adopted. The solutions for the environmental protection comprise the following activities: the reduction of quantities of waste lubricating oil, the organized collection of the waste lubricating oil and recycling of waste lubricating oil

The structure and mechanical properties of an aluminium A356 alloy base composite with Al2O3 particle additions

Composites-castings with an aluminium A356 alloy base and additions of 1, 2, and 3% (wt.) of Al2O3 reinforcement of 12µm size were made. A side by side investigation of the microstructure and hardness of the composite and the base alloy cast into a steel mould was done. According to hardness values samples of A356 + 3% Al2O3 composite with a particle size of 12µm were selected. These samples were additionally pressed in a special tooling by which tensile test samples were obtained. Application of the compocasting process led to a transformation of a dendritic to a nondendritic structure of the base alloy. The mechanical properties of the composite are improved in relation to the base alloy.