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Title: Friction and wear in hot forging of steels

Abstract

In the field of hot forging of steels, the mastering of wear phenomena enables to save cost production, especially concerning tools. Surfaces of tools are protected thanks to graphite. The existing lubrication processes are not very well known: amount and quality of lubricant, lubrication techniques have to be strongly optimized to delay wear phenomena occurrence. This optimization is linked with hot forging processes, the lubricant layers must be tested according to representative friction conditions. This paper presents the first part of a global study focused on wear phenomena encountered in hot forging of steels. The goal is the identification of reliable parameters, in order to bring knowledge and models of wear. A prototype testing stand developed in the authors' laboratory is involved in this experimental analysis. This test is called Warm and Hot Upsetting Sliding Test (WHUST). The stand is composed of a heating induction system and a servo-hydraulic system. Workpieces taken from production can be heated until 1200 deg. C. A nitrided contactor representing the tool is heated at 200 deg. C. The contactor is then coated with graphite and rubs against the workpiece, leaving a residual track on it. Friction coefficient and surface parameters on the contactor andmore » the workpiece are the most representative test results. The surface parameters are mainly the sliding length before defects occurrence, and the amplitude of surface profile of the contactor. The developed methodology will be first presented followed by the different parts of the experimental prototype. The results of experiment show clearly different levels of performance according to different lubricants.« less

Authors:
 [1];  [2]; ; ; ;  [1];  [3];  [4]
  1. LAMIH UMR CNRS 8530 - Universite de Valenciennes, Le Mont Houy - 59313 Valenciennes Cedex 9 (France)
  2. (France)
  3. CONDAT Lubrifiants- Avenue Frederic Mistral, 38670 Chasses sur Rhones (France)
  4. CETIM - Etablissement de Saint Etienne 7, rue de la Presse - BP 802, 42952 Saint Etienne Cedex 9 (France)
Publication Date:
OSTI Identifier:
21057056
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 907; Journal Issue: 1; Conference: 10. ESAFORM conference on material forming, Zaragoza (Spain), 18-20 Apr 2007; Other Information: DOI: 10.1063/1.2729567; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMPLITUDES; DEFECTS; FORGING; FRICTION FACTOR; GRAPHITE; HEATING; HOT WORKING; LAYERS; LUBRICATION; OPTIMIZATION; PERFORMANCE; SLIDING FRICTION; STEELS; SURFACES; TESTING; WEAR

Citation Formats

Daouben, E., CONDAT Lubrifiants- Avenue Frederic Mistral, 38670 Chasses sur Rhones, Dubar, L., Dubar, M., Deltombe, R., Dubois, A., Truong-Dinh, N., and Lazzarotto, L.. Friction and wear in hot forging of steels. United States: N. p., 2007. Web. doi:10.1063/1.2729567.
Daouben, E., CONDAT Lubrifiants- Avenue Frederic Mistral, 38670 Chasses sur Rhones, Dubar, L., Dubar, M., Deltombe, R., Dubois, A., Truong-Dinh, N., & Lazzarotto, L.. Friction and wear in hot forging of steels. United States. doi:10.1063/1.2729567.
Daouben, E., CONDAT Lubrifiants- Avenue Frederic Mistral, 38670 Chasses sur Rhones, Dubar, L., Dubar, M., Deltombe, R., Dubois, A., Truong-Dinh, N., and Lazzarotto, L.. Sat . "Friction and wear in hot forging of steels". United States. doi:10.1063/1.2729567.
@article{osti_21057056,
title = {Friction and wear in hot forging of steels},
author = {Daouben, E. and CONDAT Lubrifiants- Avenue Frederic Mistral, 38670 Chasses sur Rhones and Dubar, L. and Dubar, M. and Deltombe, R. and Dubois, A. and Truong-Dinh, N. and Lazzarotto, L.},
abstractNote = {In the field of hot forging of steels, the mastering of wear phenomena enables to save cost production, especially concerning tools. Surfaces of tools are protected thanks to graphite. The existing lubrication processes are not very well known: amount and quality of lubricant, lubrication techniques have to be strongly optimized to delay wear phenomena occurrence. This optimization is linked with hot forging processes, the lubricant layers must be tested according to representative friction conditions. This paper presents the first part of a global study focused on wear phenomena encountered in hot forging of steels. The goal is the identification of reliable parameters, in order to bring knowledge and models of wear. A prototype testing stand developed in the authors' laboratory is involved in this experimental analysis. This test is called Warm and Hot Upsetting Sliding Test (WHUST). The stand is composed of a heating induction system and a servo-hydraulic system. Workpieces taken from production can be heated until 1200 deg. C. A nitrided contactor representing the tool is heated at 200 deg. C. The contactor is then coated with graphite and rubs against the workpiece, leaving a residual track on it. Friction coefficient and surface parameters on the contactor and the workpiece are the most representative test results. The surface parameters are mainly the sliding length before defects occurrence, and the amplitude of surface profile of the contactor. The developed methodology will be first presented followed by the different parts of the experimental prototype. The results of experiment show clearly different levels of performance according to different lubricants.},
doi = {10.1063/1.2729567},
journal = {AIP Conference Proceedings},
number = 1,
volume = 907,
place = {United States},
year = {Sat Apr 07 00:00:00 EDT 2007},
month = {Sat Apr 07 00:00:00 EDT 2007}
}
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