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Technical Paper

History And Advances In Tempering Parameter Development

The results of the stress relieving and tempering processes of steel are dependent on the process temperature and time which are correlated using Holloman-Jaffe equation or Larsen-Miller equation. These equations yield a value known as the tempering parameter, which is a measure of the thermal effect of the process. Processes that exhibit the same tempering parameter exhibit the same effect. In this paper an overview of the development of the tempering parameter, including its origin, use and limitations will be provided. In addition, recent work describing the development of more precise numerical relationships to describe the tempering process will be provided.
Technical Paper

Quench Factor Analysis To Quantify Steel Quench Severity And Its Successful Use In Steel Hardness Prediction

Although quench factor analysis has been used by many researchers in predicting the performance of a quenchant to strengthen aluminum, it has rarely been applied to steel quenching. However, quench factor analysis posses a number of advantages over current empirical methods or more recently employed finite element thermophysical property modeling. For example, quench factor analysis can address the non-Newtonian cooling process involved with many processes utilizing vaporizable quenchants. Quench factor analysis predictions of as-quenched hardness can be successfully performed with an Excel Spreadsheet calculation. Finally, quench factors can be easily utilized in constructing databases for quenchant characterization and selection.
Technical Paper

An Accelerated Carburizing Process

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.
Technical Paper

Lubrication Applications of Coat Forming Additives

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.
Technical Paper

Surface Engineered Coatings and Surface Additive Interactions for Boundary Film Formation to Reduce Frictional Losses in the Automotive Industry: A review

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.

Fuels and Lubricants Handbook: Technology, Properties, Performance, and Testing

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
Technical Paper

Hydraulic System Cavitation: A Review

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.
Technical Paper

Review of ASTM D-2882 Hardware Problems and Suggested Solutions

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.
Technical Paper

Review of Testing Methods for Hydraulic Fluid Flammability

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.