Publication result detail

On the Relation between Friction Increase and Grease Thickener Entraining on a Border of Mixed EHL Lubrication

ZAPLETAL, T.; ŠPERKA, P.; KŘUPKA, I.; HARTL, M.

Original Title

On the Relation between Friction Increase and Grease Thickener Entraining on a Border of Mixed EHL Lubrication

English Title

On the Relation between Friction Increase and Grease Thickener Entraining on a Border of Mixed EHL Lubrication

Type

WoS Article

Original Abstract

This paper deals with an experimental study of film thickness and friction of commercial-grade grease and its base oil in a highly loaded contact. In-situ measurements were conducted for two surface textures on a ball-on-disc optical tribometer at the border of mixed lubrication. At high speeds, the film thickness and the friction of grease correspond with the base oil, while, the thickener enters the contact area and locally affects the film thickness and friction at low speeds. It was found out that the thickener starts to enter the contact area approximately at the same speed when the base oil friction increases on Stribeck curve but without direct solid to solid contact. It indicates that both effects can have the same origin. Change of lubricant flow in contact inlet area was discussed as a possible explanation.

English abstract

This paper deals with an experimental study of film thickness and friction of commercial-grade grease and its base oil in a highly loaded contact. In-situ measurements were conducted for two surface textures on a ball-on-disc optical tribometer at the border of mixed lubrication. At high speeds, the film thickness and the friction of grease correspond with the base oil, while, the thickener enters the contact area and locally affects the film thickness and friction at low speeds. It was found out that the thickener starts to enter the contact area approximately at the same speed when the base oil friction increases on Stribeck curve but without direct solid to solid contact. It indicates that both effects can have the same origin. Change of lubricant flow in contact inlet area was discussed as a possible explanation.

Keywords

film thickness; friction; grease; base oil; EHL

Key words in English

film thickness; friction; grease; base oil; EHL

Authors

ZAPLETAL, T.; ŠPERKA, P.; KŘUPKA, I.; HARTL, M.

RIV year

2021

Released

29.01.2020

Publisher

MDPI

Location

BASEL

ISBN

2075-4442

Periodical

Lubricants

Volume

8

Number

2

State

Swiss Confederation

Pages from

1

Pages to

11

Pages count

11

URL

https://www.mdpi.com/2075-4442/8/2/12/pdf

Full text in the Digital Library

http://hdl.handle.net/11012/196754

BibTex

@article{BUT170224,
  author="Tomáš {Zapletal} and Petr {Šperka} and Ivan {Křupka} and Martin {Hartl}",
  title="On the Relation between Friction Increase and Grease Thickener Entraining on a Border of Mixed EHL Lubrication",
  journal="Lubricants",
  year="2020",
  volume="8",
  number="2",
  pages="1--11",
  doi="10.3390/lubricants8020012",
  url="https://www.mdpi.com/2075-4442/8/2/12/pdf"
}

Documents

lubricants-08-00012-v2