Automotive

Tribological research has been embraced for many years in the automotive industry and PCS' range of instruments are used around the world to design and develop world leading formulations for the field.

Whether you are focused on motorbikes or lorries, on electric vehicles or petrol, in every automotive application you will find moving parts; and where you find these moving parts you find tribology. From gearboxes to brake pads our instruments have been used to drive the innovation of the automotive sector through reliable, repeatable bench top testing.

In the automotive industry the benefits of tribological research are widespread. One major benefit from the continued research and improvement of lubricant and coating formulations is the protection they offer moving parts in automotive systems. This improved protection means increased reliability, which is great for customers but also for the environment as parts need replacing less frequently.

Environmental benefits of tribological research in the automotive sector are also found in the improvement in efficiency of powertrain systems, the result of better lubricants. With estimates suggesting that 200,000 million litres of fuel are used annually to overcome friction in passenger cars, even a modest 0.1% improvement in efficiency could result in hundreds of millions of litres of fuel being saved.

Using PCS equipment, testing of contacts under conditions found in internal combustion engines can be performed, shear rates can be replicated and EHD film thicknesses can be analysed. PCS have worked closely with a large number of experts in the automotive industry for the past 30 years, and our instruments have developed to meet their ever-changing needs.

Automotive industry research areas include:

  • CV joints
  • Cam follower systems
  • Bearings
  • Gearboxes
  • Brake pads
  • Clutch pads
  • Diesel fuels

Automotive Industry includes the following:

Cars
Cars

Many aspects of cars are tribologically interesting. Extensive research into a host of components such as gearboxes, engines, bearings and brakes is ongoing around the world.

Heavy Duty Vehicles
Heavy Duty Vehicles

Like with cars, tribology research into heavy duty vehicles is ongoing and for this area higher loads are often focused on for more representative test conditions.

Motorcycles
Motorcycles

Motorcycles typically run at higher RPM than cars and heavy duty vehicles. This places different requirements on the oils and lubricants used in them, which is an area of focused research.

Motorsport
Motorsport

Tribology is even more important in motor sport than in consumer cars. The tolerances are finer and the optimisation of fuels and lubricants greater, so how surfaces interact is critical in developing the fastest racer possible.

Instruments for the Automotive Industry

Speak to us about our products

Get in touch

Automotive Industry Articles & Papers

Paper

In-situ Observations of the Effect of the ZDDP Tribofilm Growth on Micropitting

The ongoing trend for using ever lower viscosities of lubricating oils, with the aim of improving the efficiency of mechanical …

The ongoing trend for using ever lower viscosities of lubricating oils, with the aim of improving the efficiency of mechanical systems, means that machine components are required to operate for longer periods under thin film, mixed lubrication conditions where the risk of surface damage is increased. For this reason, the role of zinc dialkyldithiophosphate (ZDDP) antiwear lubricant additive has become increasingly important in order to provide adequate surface protection. It is known that due to its exceptional effectiveness in reducing surface wear, ZDDP may promote micropitting by preventing adequate running-in of the contacting surfaces. However, the relationship between ZDDP tribofilm growth rate and the evolution of micropitting has not been directly demonstrated. To address this, we report the development of a novel technique using MTM-SLIM to obtain micropitting and observe ZDDP tribofilm growth in parallel throughout a test. This is then applied to investigate the effect of ZDDP concentration and type on micropitting. It is found that oils with higher ZDDP concentrations produce more micropitting but less surface wear and that, at a given concentration, a mixed primary-secondary ZDDP results in more severe micropitting than a primary ZDDP. Too rapid formation of a thick antiwear tribofilm early in the test serves to prevent adequate running-in of sliding parts, which subsequently leads to higher asperity stresses and more asperity stress cycles and consequently more micropitting. Therefore, any adverse effects of ZDDP on micropitting and surface fatigue in general are mechanical in nature and can be accounted for through ZDDP's influence on running-in and resulting asperity stress history. The observed correlation between antiwear film formation rate and micropitting should help in the design of oil formulations that extend component lifetime by controlling both wear and micropitting damage.

View abstract

Paper

Prediction of Micropitting Damage in Gear Teeth Contacts Considering the Concurrent Effects of Surface Fatigue and Mild Wear

The present paper studies the occurrence of micropitting damage in gear teeth contacts. An existing general micropitting model, which accounts …

The present paper studies the occurrence of micropitting damage in gear teeth contacts. An existing general micropitting model, which accounts for mixed lubrication conditions, stress history, and fatigue damage accumulation, is adapted here to deal with transient contact conditions that exist during meshing of gear teeth. The model considers the concurrent effects of surface fatigue and mild wear on the evolution of tooth surface roughness and therefore captures the complexities of damage accumulation on tooth flanks in a more realistic manner than hitherto possible. Applicability of the model to gear contact conditions is first confirmed by comparing its predictions to relevant experiments carried out on a triple-disc contact fatigue rig. Application of the model to a pair of meshing spur gears shows that under low specific oil film thickness conditions, the continuous competition between surface fatigue and mild wear determines the overall level as well as the distribution of micropitting damage along the tooth flanks. The outcome of this competition in terms of the final damage level is dependent on contact sliding speed, pressure and specific film thickness. In general, with no surface wear, micropitting damage increases with decreasing film thickness as may be expected, but when some wear is present micropitting damage may reduce as film thickness is lowered to the point where wear takes over and removes the asperity peaks and hence reduces asperity interactions. Similarly, when wear is negligible, increased sliding can increase the level of micropitting by increasing the number of asperity stress cycles, but when wear is present, an increase in sliding may lead to a reduction in micropitting due to faster removal of asperity peaks. The results suggest that an ideal situation in terms of surface damage prevention is that in which some mild wear at the start of gear pair operation adequately wears-in the tooth surfaces, thus reducing subsequent micropitting, followed by zero or negligible wear for the rest of the gear pair life. The complexities of the interaction between the contact conditions, wear and surface fatigue, as evident in the present results, mean that a full treatment of gear micropitting requires a numerical model along the lines of that applied here, and that use of overly simplified criteria may lead to misleading predictions.

View abstract