Control plans for polymer quenchants
Polymer quenchants, whether used for immersion quenching or spray applications such as induction hardening, are much more difficult to control than oil quenchants. As...
Quench system design – heating and cooling
In this month’s column, we will discuss the heating and cooling of a quench tank.
All quenching fluids have an optimum operating temperature range requiring...
Different methods of aqueous polymer concentration control
In this article, I will discuss the two different methods for controlling the concentration of polymer quenchants. This is applicable to either induction spray...
Transformation of retained austenite
In this month’s column, I will discuss the transformation of retained austenite, and its stabilization.
In the last column, I reviewed the dimensional changes that...
Dimensional changes during tempering
In this column, I will discuss the dimensional changes that occur during tempering, with a short discussion of the underlying physical metallurgical changes.
Introduction
After quenching,...
Precipitation hardening stainless steels
In this column, we will discuss precipitation hardening steels and their physical metallurgy.
Precipitation hardened stainless steels are a class of stainless steels that can...
Calibration of refractometers for control of polymer quenchants
In the last column, we described the use of refractometers for controlling the concentration of many different types of fluids, including polymer quenchants and...
Application of optical refractometers for the control of concentration
Optical refractometers, analog and digital, are widely used in industrial practice to measure the concentration of coolants, polymer quenchants, and fire-resistant hydraulic fluids, and...
Determining carbon potential for neutral hardening or carburizing
To successfully heat-treat or carburize the many different alloys seen in the heat-treating shop, it is necessary to properly control the carbon potential of...
Nondestructive testing VI – Radiography
In this article, we will be discussing the use of radiography (X-rays) for the detection of flaws. In the previous articles on nondestructive testing...
Nondestructive testing Part V: Eddy current testing
In the previous column, I discussed ultrasonic testing of materials. In this column, I will be discussing Eddy Current NDT methods.
History
Eddy current testing is...
Non-destructive testing Part IV: Ultrasonic testing
In my previous articles, I have discussed dye penetrant inspection and magnetic particle inspection. In this article, I will give a brief overview of...
The basics of magnetic particle inspection
Magnetic particle inspection is a technique that is commonly used for ferromagnetic alloys for detecting surface and subsurface discontinuities. This method is extensively used...
Benefits of liquid penetrant inspection
Dye penetrant inspection is one of the most widely used non-destructive inspection techniques used. It is useful for a wide variety of product applications...
Introduction to nondestructive testing
Nondestructive testing (NDT) is an interdisciplinary science that uses many different methods to evaluate the properties of metals, parts, or assemblies without causing damage...
Fracture mechanics and fatigue crack growth
In the last article, we talked about fracture mechanics, and the method of fracture toughness testing using fracture mechanics. In this article, we are...
Back to basics – Fracture toughness testing
In previous articles, we have discussed the many different types of mechanical testing methods and requirements. While some of the test methods have application...
Back to basics – Toughness testing of material
In the last series of articles, we discussed hardness testing and tensile testing. In these applications, the loading is a static load over a...
Back to basics: Mechanical testing – the tensile test
In the previous article, we discussed hardness testing, and the various methods of hardness testing were illustrated. In this article we discuss the tensile...
Back to basics: Hardness testing, Part 2
In last month’s Hot Seat article, we began a discussion on the various methods of mechanical property testing. Overall, we are going to discuss...
