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Title: Effects of the Exposure to Corrosive Salts on the Frictional Behavior of Gray Cast Iron and a Titanium-Based Metal Matrix Composite

Abstract

The introduction of increasingly aggressive road-deicing chemicals has created significant and costly corrosion problems for the trucking industry. From a tribological perspective, corrosion of the sliding surfaces of brakes after exposure to road salts can create oxide scales on the surfaces that affect friction. This paper describes experiments on the effects of exposure to sodium chloride and magnesium chloride sprays on the transient frictional behavior of cast iron and a titanium-based composite sliding against a commercial brake lining material. Corrosion scales on cast iron initially act as abrasive third-bodies, then they become crushed, spread out, and behave as a solid lubricant. The composition and subsurface microstructures of the corrosion products on the cast iron were analyzed. Owing to its greater corrosion resistance, the titanium composite remained scale-free and its frictional response was markedly different. No corrosion scales were formed on the titanium composite after aggressive exposure to salts; however, a reduction in friction was still observed. Unlike the crystalline sodium chloride deposits that tended to remain dry, hygroscopic magnesium chloride deposits absorbed ambient moisture from the air, liquefied, and retained a persistent lubricating effect on the titanium surfaces.

Authors:
 [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
931651
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Tribology International; Journal Volume: 40; Journal Issue: 09
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 36 MATERIALS SCIENCE; CAST IRON; CORROSION; CORROSION PRODUCTS; CORROSION RESISTANCE; MAGNESIUM CHLORIDES; SODIUM CHLORIDES; SOLID LUBRICANTS; TITANIUM; brakes; friction; cast iron; titanium alloys; metal matrix composites

Citation Formats

Blau, Peter Julian, Truhan, Jr., John J, and Kenik, Edward A. Effects of the Exposure to Corrosive Salts on the Frictional Behavior of Gray Cast Iron and a Titanium-Based Metal Matrix Composite. United States: N. p., 2007. Web. doi:10.1016/j.triboint.2007.02.020.
Blau, Peter Julian, Truhan, Jr., John J, & Kenik, Edward A. Effects of the Exposure to Corrosive Salts on the Frictional Behavior of Gray Cast Iron and a Titanium-Based Metal Matrix Composite. United States. doi:10.1016/j.triboint.2007.02.020.
Blau, Peter Julian, Truhan, Jr., John J, and Kenik, Edward A. Mon . "Effects of the Exposure to Corrosive Salts on the Frictional Behavior of Gray Cast Iron and a Titanium-Based Metal Matrix Composite". United States. doi:10.1016/j.triboint.2007.02.020.
@article{osti_931651,
title = {Effects of the Exposure to Corrosive Salts on the Frictional Behavior of Gray Cast Iron and a Titanium-Based Metal Matrix Composite},
author = {Blau, Peter Julian and Truhan, Jr., John J and Kenik, Edward A},
abstractNote = {The introduction of increasingly aggressive road-deicing chemicals has created significant and costly corrosion problems for the trucking industry. From a tribological perspective, corrosion of the sliding surfaces of brakes after exposure to road salts can create oxide scales on the surfaces that affect friction. This paper describes experiments on the effects of exposure to sodium chloride and magnesium chloride sprays on the transient frictional behavior of cast iron and a titanium-based composite sliding against a commercial brake lining material. Corrosion scales on cast iron initially act as abrasive third-bodies, then they become crushed, spread out, and behave as a solid lubricant. The composition and subsurface microstructures of the corrosion products on the cast iron were analyzed. Owing to its greater corrosion resistance, the titanium composite remained scale-free and its frictional response was markedly different. No corrosion scales were formed on the titanium composite after aggressive exposure to salts; however, a reduction in friction was still observed. Unlike the crystalline sodium chloride deposits that tended to remain dry, hygroscopic magnesium chloride deposits absorbed ambient moisture from the air, liquefied, and retained a persistent lubricating effect on the titanium surfaces.},
doi = {10.1016/j.triboint.2007.02.020},
journal = {Tribology International},
number = 09,
volume = 40,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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