Tribology Transactions back issues from April 2007:
New Test for Mild Lubricated Wear in Rolling-Sliding Contacts
Apr 01, 2007; ... A new test method for measuring and studying mild, lubricated wear is described. The test combines three important characteristics, (i) a mixed rolling-sliding contact to minimize contact geometry changes during a test; (ii) contra-rotating test specimen, to produce slide-roll ratios of greater ...
Performance Characteristics of Jet Fuel in Heavily Loaded Contacts
Apr 01, 2007; ... Friction coefficient, bearing performance (i.e., torque generation and temperature rise), and rolling contact fatigue of steel and ceramic (silicon nitride) materials operating in the presence of JP-8+100 jet fuel and Mil-L-23699 turbo jet oil were investigated. A ball-on-disk test machine was ...
The Role of Hydrogen Atmosphere on the Tribological Behavior of Non-Hydrogenated DLC Coatings against Aluminum
Apr 01, 2007; ... Diamond-like carbon (DLC) coatings are promising candidates as tool coatings for dry machining of aluminum alloys as aluminum has a lower tendency to adhere to the DLC surface when compared to other hard coatings in ambient conditions. This study investigated the tribological behavior of ...
Grease Degradation in R0F Bearing Tests
Apr 01, 2007; ... This paper is the second in a series that examines grease lubrication mechanisms and failure in rolling element bearings. The aim of the work was to understand the grease condition changes during use and the relationship to lubrication performance and failure. R0F bearing tests were carried out ...
A Tribological Study for an Increased Coefficient of Friction in the Extraction of Sugarcane Juice
Apr 01, 2007; ... Historically, the roughening of the surface of sugarcane mill roller shells has been done by a shielded metal arc-welding process (SMAW), which is called "arcing" in the sugar industry. In this method, discrete weld globules are deposited on the grey cast iron mill roller shell surface, a ...
Study Demonstrating Enhanced Oxidation Stability when Arylamine Antioxidants are Combined with Organic Molybdenum Complexes
Apr 01, 2007; ... An oil-soluble additive organic molybdenum complex (MC) was synthesized. The antioxidation properties of a formulation including polyalphaolefin synthetic lubricant (PAO), the complex of p,p.-dioctyldiphenylamine (DODPA) and MC, were evaluated by a differential scanning calorimetry (DSC) test ...
Formation Mechanism of a Low Friction ZDDP Tribofilm on Iron Oxide
Apr 01, 2007; ... In a previous study, an iron oxide layer (mixture of Fe^sub 3^O^sub 4^ and FeO) formed by water-vapor treatment on a steel plate resulted in an anomalous low friction (μ < 0.06) when slid against a steel cylinder in a lubricant containing ZDDP. This value is about a half of a steel/steel ...
Study of Surface Films of the ZDDP and the MoDTC with Crystalline and Amorphous Overbased Calcium Sulfonates by XPS
Apr 01, 2007; ... The role of amorphous or crystalline overbased detergent and sulfur containing AW/EP additives on the surface films created in a tribometer was investigated. In the crystalline overbased sulfonate containing samples the weld point was higher than for the equivalent blend using an amorphous ...
Deterministic Modeling of Honed Cylinder Liner Friction
Apr 01, 2007; ... An experimental apparatus and an analytical model have been developed to investigate and determine the lubrication condition and frictional losses at the interface between a piston ring and a honed cylinder liner (PRCL). The experimental apparatus was used to measure the friction at the PRCL ...
Effect of Electron Radiation on the Tribological Properties of Polyimide
Apr 01, 2007; ... The blocks of polyimide (PI) were irradiated with 1.7 MeV electrons in four doses of 1 × 10^sup 5^, 5 × 10^sup 5^, 2.5 × 10^sup 6^, and 5 × 10^sup 6^ Gy under N^sub 2^ atmosphere. The changes of the polyimide surface after radiation were characterized by Fourier transform infrared spectroscopy ...
Antioxidant Activity of 3,7-Di-iso-octyl-phenothiazine and Its Synergistic Effect with 4,4'-Di-iso-octyl-diphenylamine
Apr 01, 2007; ... The antioxidant activity of 3,7-di-iso-octyl-phenothiazine and 4,4'-di-iso-octyl-diphenylamine as well as their mixtures in PAO 166 were studied. The results showed that 3,7-di-iso-octyl-phenothiazine performed much better than its starting material 4,4'-di-iso-octyl-diphenylamine in terms of ...
Highly Crosslinked Polyethylenes in Hip Replacements: Improved Wear Performance or Paradox?
Apr 01, 2007; ... The lubrication and wear of artificial joints are important issues for their longevity. Bone loss caused by the biological response (osteolysis) to the wear debris leads to implant loosening and eventual failure of the device. Various studies have shown that the size, shape, and the number of ...