Thermal expansion of mineral oil quenchants

In this column, I will discuss the thermal expansion of oil. This information is primarily important for initial fills of a quench tank. Introduction Oil, when...

The effect of catalysts on quench oil oxidation

In the last column, I discussed the effect of temperature on the oxidation of a quench oil. As was alluded to in my last...

Effect of temperature on oxidation of oil quenchants

In this column, I will discuss the effect of temperature on the oxidation behavior of martempering oil used for distortion control. Introduction Martempering oils are used...

The mechanism of creep and its stages

In this column, I will discuss the mechanism of creep and its three stages. Applications of metals at elevated temperatures involve several problems. It is...

Intergranular corrosion of austenitic stainless steels

In this column, I will discuss the intergranular corrosion of austenitic stainless steels (3XX) and discuss the thermal processing causes. Introduction Austenitic stainless steels, such as...

Cooling rate after tempering

In this column, I will discuss the effect of cooling rate after tempering. Introduction During heat treatment of steel, the process is generally austenitize, quench, and...

Intergranular oxidation in carburizing steels

Intergranular oxidation (IGO) in carburizing steels is detrimental to carburized gear performance. It reduces fatigue performance and can contribute to surface spalling. This article...

Hardening power: A measure of quenching performance

In this column, we will discuss the Segerberg Hardening Power (HP) for polymer quenchants.  When comparing polymer quenchants, there are several things that we look...

Calculating decarburization 

In this column, I will be talking about decarburization of steel and how to calculate its depth. Introduction Decarburization of steel is the depletion of carbon...

The effect of temperature on cooling curve behavior

In this column, we will discuss the effect of temperature on the cooling curve behavior of quench oils. Development of Quench Oil Maximum Operating Temperature The...

The effect of agitation on oil quenchants

In this column, I will discuss the effect of agitation on the cooling curve of oil quenchants. Oil has been used for many years as...

Quenching from molten salt into polymer quenchants

In this column, I will discuss quenching aluminum from molten salt into a polymer quenchant. A molten salt bath is a common method of heating...

Blistering of aluminum during heat treatment

In this column, we will discuss the blistering of aluminum during heat treatment, and methods to prevent its occurrence. Introduction High-temperature oxidation, or blistering, often occurs...

Quench factor analysis: C-curve determination

Previously, I discussed the concept of the quench factor, as developed by Staley . We showed that it was possible to determine properties as...

Quench factor analysis: quench factor determination

In this column, we will discuss the determination of the quench factor as it is used in quench factor analysis. This will lead into...

Quench Factor analysis used to predict properties of quenched and aged aluminum

In this column, we will start to discuss the application of Quench Factor Analysis (QFA) to predicting properties of quenched and aged aluminum. Quench Factor...

Control of distortion in heat-treated aluminum

In this column, we will discuss controlling the distortion of aluminum heat-treated components. The heat treatment of aluminum (solution heat treatment, quenching and aging) are...

Heat-treating workhorse – integral quench furnace

In this column, we will discuss the workhorse of the steel heat-treating industry – the integral quench furnace. The integral quench furnace, or sealed quench...

Understanding the effect of boron in steels

In this column, we will discuss the effect of boron additions to steel and its influence on properties. Boron, B, is an element with an...

Safety considerations when quenching with oil or salt

In this column, we will consider safety aspects of quenching with oil or molten salt. Heat treating is a manufacturing process where the goal is...

Classifying non-metallic inclusions in steels

In this column, we will discuss the different types of inclusions present in steels and discuss their physical metallurgy. As property requirements increase, and...

Revisiting the 1:1 Rule for oil quenchants

The rule of thumb “one gallon of oil to one pound of parts and fixtures” has been in the literature for a long time....

Quench tank agitation by submerged jets

In this column, I will discuss agitation by submerged jets. Common methods of agitating quench tanks, and other types of tanks, are by sparging or...

Influence of agitation on polymer quenchants

Polymer quenchants are used extensively to quench a large variety of materials in a variety of processes. Polymer quenchants can be used for immersion...

Sampling of quench oil for proactive maintenance

In this column, I will discuss the sampling of quench oil for quarterly checks as required by many internal and external auditing agencies (CQI-9,...

Compatibility of polymer quenchants with metals, seals

In this column, I will discuss the compatibility of polymer quenchants and materials used in the construction of quench tanks, heat exchangers, and pump...

Using water as a quenchant

In this short column, we will discuss quenching with water. As a quenching medium, plain water approaches the maximum cooling rate attainable in a...

Understanding the basics of spray quenching

Spray quenching involves the removal of heat by the impingement of a liquid quenchant on a hot metal surface. Examples include: Fog quenching. Quenching...

Estimating required flow through quench tanks

In this month’s column, I will discuss a method of estimating the required flow for a quench tank. Agitation has a significant effect on...

Use of molten salts for martempering of steel

In July’s column, I talked about molten salts and the different types. In this short column, we discuss the benefits of using molten salts...

Use of molten salt in heat treatment

At the turn of the 20th century, the use of molten salt as a heating and quenching medium for steels was developed in England....

Finding data needed for modeling and simulation

Modeling and simulation have become an important part of the design and manufacturing toolbox. Modeling and simulation are used in forging, casting, machining, forming,...

Thermal separation of polyalkylene glycol quenchants

Polyalkylene glycol quenchants are used in a variety of different heat-treating applications. One very common application is quenching of large steel and aluminum components....

Heat treatment of aluminum Part VII – Hardness and conductivity

In the previous article, we discussed the artificial aging of aluminum. Once we have heat treated the parts, we need to verify the properties....

Heat treatment of aluminum VI – Artificial aging

In the previous column, we described the fundamentals of natural aging. In natural aging, the solid solution obtained after quenching starts to form precipitates...

Heat treatment of aluminum, Part V

After quenching and any straightening, the supersaturated solid solution of aluminum wants to reach equilibrium. It does this through the process of precipitation hardening....

Heat treatment of aluminum IV: Handling distortion

After quenching, depending on the quenchant used, distortion of parts can occur. This is particularly true for water-quenched parts. Parts must be straightened. This...

Heat treatment of aluminum, quenching Part III

In the last article, we discussed quenching of aluminum, and the importance of rapid quenching to prevent the formation of precipitates at the grain...

Heat treatment of aluminum, part II: Water quenching

In the last article, we talked about the metallurgy behind quenching aluminum. Now we are going to discuss the available quenchants for aluminum. Introduction To achieve...

Heat treatment of aluminum – Part I: Quenching basics

In previous articles, we discussed the role of alloying elements and discussed the solution heat treatment of aluminum. We showed that it is important...