Hardness and Hardenability Archives

One Minute Mentor: Transformation behavior of Austenite

The transformation behavior of retained austenite in M2 steel was examined under varying tempering conditions. The steel was initially subjected to interrupted quenching at 105 °C (225 °F), a process that elevated the retained austenite content to approximately 55 vol %, compared to the typical 25 vol % observed after direct quenching to room temperature. This was followed by tempering at 565 °C (1050 °F), without intermediate cooling. Results indicated that double tempering was significantly more effective than single tempering at transforming retained austenite under these conditions. Furthermore, repeated tempering cycles accelerated the complete transformation of retained austenite, achieving full conversion in a shorter total processing time than single-stage tempering.

For more information, click on the link below (subscription required). Then scroll to Figure 5.Jon L. Dossett; George E. Totten, Control of Distortion in Tool Steels, ASM International, 2014 https://doi.org/10.31399/asm.hb.v04d.9781627081689

High-impact research to be revealed at Heat Treat 2017

More than 125 presentations of original, unpublished work will be delivered when the ASM Heat Treating Society convenes for its 29th conference and exhibition in Columbus, Ohio, October 24-26. The information exchanged in these sessions – as researchers and practitioners share their latest discoveries, theories, and advancements – will have a significant impact on design and manufacturing innovation as well as the fortunes of industry.

Researchers develop a unique quantum mechanical approach to determining metal ductility

A team of scientists from Ames National Laboratory and Texas A&M University developed a new way to predict metal ductility.

Applied Process and others to begin doing business as Aalberts surface technologies

Applied Process and other U.S. based thermal processing, surface treatment businesses will begin doing business as Aalberts surface technologies.

One Minute Mentor: Maps of Wear Resistance

The images show wear maps for (a) treated and (b) nontreated 316 stainless steel. The T316 stainless steel was treated by low-temperature carburization.

One Minute Mentor: Hardness Depth Profiles of Stainless Steel after Nitriding and Nitrocarburizing

X-ray diffraction analysis indicates that the hardened case consists of a mixture of expanded austenite and expanded martensite.

One Minute Mentor: Nitrogen-Expanded Austenite

The graph shows hardness-depth profiles of nitrided AISI 316. A profile for carburizing is shown for comparison.

One Minute Mentor: Physical Metallurgy of Expanded Austenite

The microstructural feature responsible for the favorable technological properties resulting from low-temperature gaseous thermochemical treatment is a supersaturation of nitrogen and/or carbon in austenite. This is called expanded austenite.

One Minute Mentor: Low-Temperature Surface Hardening of Stainless Steel

The graph shows a schematic time-temperature-transformation (TTT) diagram of austenite with a high nitrogen or carbon content. In order to prevent the development of chromium nitrides/carbides, a long-time low-temperature treatment could be applied.

One Minute Mentor: Iron-Nickel Precipitation-Hardenable Superalloys

It is important to note that tensile properties are influenced not only by heat treatment, but also by control of structure during thermomechanical processing.

One Minute Mentor: Hardening Martensitic Stainless Steels

Certain anomalies in these steels that should be considered before specifying a heat-treating procedure are exemplified in the opposing injurious effects of the high and low extremes of austenitizing temperature, depending on the subsequent tempering temperature.

One Minute Mentor: Hardening Ferritic Stainless Steels

Ferritic stainless steels are quite similar in their mechanical behavior to carbon steel.

One Minute Mentor: Alpha-Prime Inhibits Toughness in Ferritic Stainless Steels

The graph shows how alpha-prime formation reduces toughness in ferritic stainless steels.

One Minute Mentor: Influence of Chromium on Ferritic Stainless Steels

Ferritic stainless steels are quite similar in their mechanical behavior to carbon steel.

One Minute Mentor: Tempering Corrosion-Resistant Tool Steels

During tempering, the combination of properties such as hardness, toughness, and corrosion resistance, as well as residual stresses, can be adjusted within a wide range

One Minute Mentor: Carburizing Tool Steels

P20 mold steel is seldom carburized for molds used in compression molding, particularly for molding the more abrasive plastics.

One Minute Mentor: Tempering Temperature and Corrosion Properties

The graph shows the corrosion resistance of martensitic stainless steels with high hardness. It compares nitrogen alloyed grade (M340 = AISI 440Mod) with the standard grade AISI 440C.

One Minute Mentor: Tempering Behavior of Corrosion-Resistant Tool Steels

During tempering, the combination of material properties such as hardness, toughness, and corrosion resistance, as well as residual stresses, can be adjusted within a wide range

One Minute Mentor: Hardness Gradients in Nitrided High-Speed Tool Steel

The graph shows the effect of bath conditions and immersion time on hardness gradients in Type T1 high-speed tool steel.

One Minute Mentor: Tempering Tool Steels

As shown in the graph for an M2 steel austenitized at 2225°F, the hardness of high-speed steel is directly affected by tempering temperature and time.

One Minute Mentor: How Austenitizing Temperature Affects High-Temperature Hardness

The austenitizing temperature affects not only the final hardness but also the grain size.

One Minute Mentor: Effect of Austenitizing Temperature on Hardness

The graph illustrates the improved toughness of M2, as measured by the Izod unnotched impact test, that results from the use of lower-than-normal austenitizing temperatures.

One Minute Mentor: Heat Treatment of a Premium Grade H13 Die

The graph shows a continuous cooling test in which the austenitizing temperature was approximately 1040°C (1900°F).

One Minute Mentor: Quenching of Hot-Work Tool Steels

Hot-work steels range from high to extremely high in hardenability, so it is possible for them to achieve full hardness by cooling in still air. However, this is not recommended, because intense embrittlement occurs after slow cooling from hardening temperature.