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One of the most commonly used tests to evaluate the antiwear properties of a hydraulic fluid is ASTM D 2882 which is based on a Vicker's V-104 vane pump. Although this is a commonly used test, the results are subject to numerous potential problems in both testing procedure and pump hardware. In this paper, the particular focus will be placed on potential problems that may be encountered with testing of water-glycol hydraulic fluids which may lead to erroneous and non-reproducible results.

Atmosphere carburizing remains one of the most important surface treatment technologies throughout the world. In this paper, various important metallurgical design variables are identified by examining the results of the carburisation of 15HN steel. These results showed the importance of the formation of martensite-retained austenite-carbide microstructure after hardening. Increasing austenization temperature causes a decrease in the carbide fraction and an increase in the fraction of retained austenite. By optimisation of the composition of these microstructures through variation of carburisation process, hardening, and tempering variables, it is possible to optimise compressive stresses, abrasive wear resistance, and contact fatigue resistance.

Surface engineering encompasses numerous vital and diverse technologies in the design and wear of automotive and off-highway components. These technologies include CVD, PVD, ion implantation and conventional heat treatments such as carburizing, nitriding and carbonitriding. Although these technologies are well known, it is considerably more difficult to understand the relative importance of the various technology niches for these processes, and it is very difficult to find effective summaries of the impact of these technologies on comparative lubrication formulation and practice. The objectives of this paper are two-fold. One is to review the impact of surface engineered coatings on the surface chemistry of steel. The second objective is to review the impact of the surface chemistry obtained by different surface treatments on boundary film formation to reduce frictional losses during fluid lubrication.

The effect phase composition of carburized constructional steels with a particular focus on the influence of retained austenite and carbides on hardness, impact strength and wear resistance is described. It is shown that increasing retained austenite and carbide content of the hardened carburized layers exhibits useful properties.

This paper describes the use of computational simulation to examine the heat transfer properties and resulting residual stress obtained by quenching a standard probe into various quench oils. Cooling curves (time-temperature profiles) were obtained after immersing a preheated 12.5 mm dia. × 60 mm cylindrical Inconel 600 (Wolfson) probe with a Type K thermocouple inserted into the geometric center into a mineral oil quenchant. Different quenching conditions were used, as received (“fresh”) and after oxidation. Surface temperatures at the cooling metal - liquid quenchant interface and heat transfer coefficients are calculated using HT-Mod, a recently released computational code. Using this data, the temperature distribution was calculated. The corresponding residual stresses were calculated using ABAQUS. This work illustrates potential benefits of computational simulation to examine the expected impact of different quenchants and quenching conditions on a heat treatment process.

Although considerable research has been performed to quantitatively compare the relative fire-resistance afforded by different hydraulic fluids in various industrial applications, new standards reflecting these developments is still incomplete. The objective of this paper is to provide an overview of the classical tests that have, and are currently, used to quantify relative fire safety of fluids. This will be complemented by a discussion of recent test developments that could be incorporated into future standards.

The ASTM test method D-2882 (Standard Test Method for Indicating the Wear Characteristics of Petroleum and Non-Petroleum Hydraulic Fluids in a Constant Volume Vane Pump) is widely used to evaluate hydraulic fluids. Performing this method can be difficult due to problems with the pump hardware and the written procedure. This paper discusses the problems and suggests possible remedies.

There is increasing interest in the development of bench tests to characterize the performance of hydraulic fluids in order to minimize the cost of testing and the volumes of fluid currently required for pump testing. One method which permits comprehensive characterization of the boundary, mixed EHD and EHD wear regimes encountered in pump lubrication is to develop a performance map. This paper discusses the use of this testing method to characterize the performance of two experimental hydraulic fluid formulations.

Currently, the industry standard pump test which is used to evaluate the lubricating performance of hydraulic fluids is ASTM D-2882 [1,2]. This test, and others, utilizes the Vickers V-104 vane pump [3]. Although ASTM D-2882 has been an industry standard for many years, it does not provide the necessary correlation required for prediction of the lubricating properties of a hydraulic fluid in various piston pump operations. The objective of this paper is to detail the recently proposed Rexroth Piston Pump Test which is being proposed as an ASTM standard. A description of the proposed hardware, pump testing strategies and methods of standardized wear determination will be provided.

Recently, a report was issued describing the use of an alternative to the commonly used thermocouple-probe assemblies for gathering time-temperature data to simulate microstructure, hardness and residual stresses of large castings of crack-sensitive steel alloys. This process involves the measurement of the increase of the water temperature in the quenching tank as a function of time as if the quench tank were a macro-calorimeter. From this data, cooling curves may be calculated which are then used to predict microstructure and hardness. However, no details of the actual modeling process used in that work have been published to date. This paper describes the results of a laboratory study which was recently performed using a round AISI 4140 steel bar to evaluate the feasibility of using water temperature rise during a quenching to generate a cooling curve for property prediction by simulation in a manner similar to that reported earlier.

One of the ongoing needs in the materials industry is to facilitate significant production cost saving due to energy usage. One way to do this is to use the thermal energy generally emitted during heat treatment to facilitate additive reactions with the material surface. This has been successfully done by formulating specific lubricity additives into on a oil or aqueous quenching media. When the material is heated and subsequently quenched, the lubricity additive will then react with the surface providing substantial improvements in lubricity. This process is called: “coat forming”. The objective of this paper is to provide an overview of coat forming reactions, additives, and subsequent application performance.

Cavitation is the dynamic process of gas cavity growth and collapse in a liquid. These cavities are due to the presence of dissolved gases or volatile liquids and they are formed at the point where the pressure is less than the saturation pressure of the gas (gaseous cavitation) or vapor pressure (vaporous cavitation). In this paper, various hydraulic system design factors and fluid properties affecting the cavitation process, and bubble collapse mechanisms will be discussed. In-situ generation of cavitation, examination of the cavitation process in model hydraulic systems, material effects and test methods will be reviewed.

This well-referenced handbook is comprehensive, in-depth, and provides a detailed overview of ALL of the important ASTM and non-ASTM fuels and lubricants test procedures. Readers will get a thorough overview of the application-related properties being tested and an extensive discussion of the principles behind the tests and their relationship to the properties themselves. A must-have for anyone in the industry involved in the formulation, use, and specification of fuels and lubricants. The information is subdivided into four sections: Petroleum Refining Processes for Fuels and Lubricant Basestocks Fuels Hydrocarbons and Synthetic Lubricants Performance/Property Testing Procedures

This new book provides a comprehensive overview of various lubrication aspects of a typical powertrain system including the engine, transmission, driveline, chassis, and other components. The manual addresses major issues and current development status of automotive lubricant test methods. Topics also cover advanced lubrication and tribochemistry of the powertrain system, such as diesel fuel lubrication, specialized automotive lubricant testing development, filtration testing of automotive lubricants, lubrication of constant velocity joints, and biodegradable automotive lubricants.

For many years the ASTM D2882 test method, using the V-104C Vane pump, served the industry well to evaluate the lubricating properties of hydraulic fluids at low pressures (< 2000 psi). However, at higher pressures in different types of pumps (i.e. piston pumps), this method may not be reliable enough to predict satisfactory lubrication performance in commercial applications. In this paper the V-104C pump will be evaluated in terms of vane contact force and film thickness parameters to assertain the possibility of using a modified bench test to better predict hydraulic fluid performance at higher pressures.

One of the most important heat treating processes is steel carburizing. However, the relatively long process times makes carburizing (and related thermochemical processes) a particularly energy consumptive and expensive process. Thus, if significant reductions in process times or temperatures can be achieved, this would result in substantial product cost savings and reduced energy consumption. Various methods of accelerating the carburizing process have been reported previously including: the use of rare earth metals, optimization by computer control of endo gas composition, use of superficial nitriding and others. In this paper, an overview of a new process using a hydrocarbon decomposition reaction catalyst that results in substantial diffusion rate acceleration and/or the potential use of significantly lower carburization temperatures will be discussed.