G. E. Totten

Quenching Theory and Technology, Second Edition

Hardening of Steels, L. de C.F. Canale and G.E. Totten Quenching of Aluminum Alloys, R.T. Shuey and M. Tiryakiogliu Quenching of Titanium Alloys, L. Meekisho, X. Yao, and G.E. Totten Mechanical Properties of Ferrous and Nonferrous Alloys after Quenching, H.-J. Spies Thermo- and Fluid-Dynamic Principles of Heat Transfer during Cooling, F. Mayinger Heat Transfer during Cooling of Heated Metals with Vaporizable Liquids, R. Jeschar, E. Specht, and C. Kohler Wetting Kinematics, H.M. Tensi Wetting Kinetics and Quench Severity of Selected Vegetable Oils for Heat Treatment, K.N. Prabhu Residual Stresses after Quenching, V. Schulze, O. Vohringer, and E. Macherauch Effect of Workpiece Surface Properties on Cooling Behavior, F. Moreaux, G. Beck, and P. Archambault Determination of Quenching Power of Various Fluids, H.M. Tensi and B. Liscic Types of Cooling Media and Their Properties, W. Luty Gas Quenching, G. Belinato, L. de C.F. Canale, and G.E. Totten Techniques of Quenching, H.E. Boyer, P. Archambault, and F. Moreaux Intensive Steel Quenching Methods, N.I. Kobasko Prediction of Hardness Profi le in Workpiece Based on Characteristic Cooling Parameters and Material Behavior during Cooling, H.M. Tensi and B. Liscic Simulation of Quenching, C. Simsir and C. Hakan Gur Appendices Index

Wear and corrosion resistance of pack chromised carbon steel

Abstract Pack chromising treatment is an environmentally friendly alternative to hard chromium to form wear and corrosion resistant surface layers. In this work, samples of AISI 1060 steel were pack chromised for 6 and 9 h at 1000 and 1050°C using different activator concentrations. Wear tests were performed in dry conditions and corrosion tests in natural sea water for the pack chromised samples and hard chromium. Pack chromising yielded the formation of layers with high chromium concentrations, high hardness and wear resistance. Increasing activator concentration causes no significant change on the morphology and thickness of the layers. The layers produced at 1050°C yielded only a (Cr,Fe)2N1−x phase, and those obtained at 1000°C are composed of a carbide mixture with (Cr,Fe)2N1−x. The sample treated at 1050°C for 9 h resulted in an optimum condition by means of better wear resistance and corrosion properties, which were close to that exhibited by the hard chrome, indicating that pack chromising is a promising alternative.

Intensive quenching Part 2 – Formation of optimal surface compressive stresses

In Part 1 of this series, an overview and process description of intensive quenching was provided. Generally, it was shown that intensive quenching processes typically involve cooling rates significantly in excess of even those traditionally exhibited by brine and caustic solutions and that these processes, which may involve time quenching, are conducted in a manner that yields optimal surface compressive stresses. The formation of such stresses not only substantially improves fatigue and impact strength properties, but also yields reduced propensity for cracking and deformation. In this paper, the metallurgical processes that are involved in the formation of these surface compressive stresses, which typically exceed even those formed by induction hardening and carburising, will be described.

Intensive quenching Part 1 – What is it?

Abstract Various intensive quenching processes have been reported since the 1920s. A historical overview of these processes is given. Based on the limited information that has been published, it is likely that many of these systems employed neither intensive quenching processing nor did they produce maximum surface compressive stresses. The objective of the present paper is to define intensive quenching, explaining how it could be used and its processes and advantages.

Plasma nitriding and nitrocarburising of a supermartensitic stainless steel

Supermartensitic stainless steels (SMSSs) are a new generation of the classic 13%Cr martensitic steels, lower in carbon and with additional alloying of nickel and molybdenum offering better weldabilty and low temperature toughness. Several works have shown that plasma nitriding and nitrocarburising of stainless steels at low temperatures produces a hard surface layer which results in increased wear resistance. In this work, SMSS samples were plasma nitrided and nitrocarburised at 400, 450 and 500uC. The plasma treated SMSS samples were characterised by means of optical microscopy, microhardness, X-ray diffraction and dry wear tests. The thickness of the layers produced increases as temperature is raised, for both plasma nitriding and nitrocarburising. X-ray diffraction demonstrates that the chromium nitride content grows with temperature for nitriding and nitrocarburising, which also showed increasing content of iron and chromium carbides with temperature. After plasma treating, it was found that the wear volume decreases for all temperatures and the wear resistance increased as the treatment temperature was raised. The main wear mechanism observed for both treated and untreated samples was grooving abrasion.

Uphill quenching of aluminium: a process overview

Uphill quenching is a relatively little known process to reduce quenching stresses in heat treatable aluminium alloys. This process involves solutionising of the alloy followed by cold water quench...

Microstructural Characterization of Layers Produced by Plasma Nitriding on Austenitic and Superaustenitic Stainless Steel Grades

Dept. of Mechanical and Materials Engineering Portland State Univ., P.O. Box 751, Portland, OR, 97207-0751

Effect of binders and surface finish on wear resistance of HVOF coatings

Abstract The high velocity oxygen fuel (HVOF) thermal spray process produces highly wear and/or corrosion resistant coatings. Tungsten carbide with a metallic binder is often used for this purpose. In this work, tungsten carbide coatings containing cobalt or nickel binder were produced by HVOF and characterised by optical and electron microscopy, hardness and a dry sand/rubber wheel abrasion test. The HVOF process produced dense coatings with low porosity levels and high hardness. The wear resistance of the specimens, which were surface treated, increased as the roughness percentage decreased. Tungsten carbide nickel based coating yielded the best wear resistance in the as sprayed condition. However, the wear rate and wear of the two coatings converged to the same values as the number of revolutions increased. Wear behaviour in the ground condition was similar, although the tungsten carbide cobalt based coating yielded better performance with increasing distance travelled during the wear test.

Cooling Capacity of Coconut Oil, Palm Oil, and a Commercial Petroleum Oil by Solving the Heat Conductivity Inverse Problem

The cooling capacity of coconut oil, palm oil, and petroleum oil were determined by solving the inverse problem (IP) using the newly developed commercial code, IQLab. It was shown that all of the oils exhibited shock-film-boiling, film-boiling, and convection-heat-transfer modes during the quenching process. The results of these investigations are necessary when developing a global database of the cooling capacity of different quenchants. The results obtained by solving the inverse problem are compared with simplified calculation results based on cooling time–temperature data obtained by using a multi-thermocouple Inconel 600 probe. The results obtained showed that the results from both methods agreed within ±10 %. These results suggest that the standard Inconel 600 probe can be used in many cases for determining average heat-transfer coefficients occurring when using vegetable oils, such as coconut oils, palm oils, and petroleum oils as quenchants.

Influence of alloying elements Cu, Ni and Mo on mechanical properties and austemperability of austempered ductile iron

Austempered ductile iron (ADI) is the most recent development in the nodular iron family. The austempering treatment produces a unique microstructure, ausferrite, which provides high mechanical strength combined with ductility, toughness, and good fatigue and wear resistance. The effect of alloying elements Cu, Ni and Mo on the mechanical properties and austemperability of ADI is reported. The mechanical strength and toughness decreased with the addition of Mo, but both wear resistance and austemperability increased with Mo content.