Four basic types of fracture mechanisms: Part II
In the previous article, we discussed the fracture surfaces that are apparent for ductile or overload type fractures, and the fractures that occur with...
Four basic types of fracture mechanisms
When a component fails, the fracture surface of the broken component can tell a great deal regarding the mechanism of failure. It can often...
Cost, cleanliness, carbon footprint affect quenchant
Vegetable oils are seeing increased interest as quenchants for steel because of low carbon footprint, a renewable resource, and the ability to reclaim/recycle into...
Quench system monitoring requirements in AMS 2759G
AMS 2759G Heat Treatment of Steel Parts, General Requirements was adopted April 23, 2019. This important aerospace specification governs the heat treatment of...
Reclamation and recycling of quench oil
Because of the cost, many captive and commercial heat treaters are looking at reclaiming or recycling their quench oil as a method of saving...
Back to basics with tempering (Part II)
After a part has been austenitized and quenched, it must be tempered. As was discussed previously , the purpose of tempering is to relieve...
Back to basics: The mechanism of quenching
Regardless of the product, it is likely that it is heat-treated and quenched. Engine components are heat-treated for wear and durability (Figure 1). Aircraft...
Back to basics: Austempering and its advantages
In the previous articles, we discussed the processes of quench and temp, and martempering. In quench and tempering, the part is heated to the...
Back to basics: Martempering to reduce distortion
In the previous article, we discussed the principle of quench and temper, which is arguably the most common type of steel heat-treating. In this...
Back to basics: Quenching, tempering as heat treatments
This article describes the most common type of heat treatment of steel. This includes austenitizing, quenching, and tempering. In this process, the part is...
Getting back to basics with tempering
Once a part has been quenched, it must be tempered. This accomplishes two things: First, it relieves the thermal and transformational stresses from quenching....
Understanding the different types of heat treating
In the last article, we discussed many different types of annealing, and the reduction of distortion by application of stress relief annealing. In this...
Understanding different types of heat treatment: Annealing
In the last few installments we discussed the use of Time-Temperature-Transformation and Continuous Cooling Transformation diagrams to understand the phase changes that occur during...
Continuous Cooling Transformation Diagrams
In the last column, we discussed the construction and application of Time Temperature Transformation or Isothermal Transformation diagrams. It was shown how these diagrams...
The Time-Temperature-Transformation Curve
In the previous column, we discussed the formation of the Iron-Carbon phase diagram. This diagram allowed us to estimate the microstructure under non-equilibrium conditions....
Back to basics on heat-treatment of steel, underlying metallurgy
In this article, and future articles, we will discuss the basics of the heat-treatment of steel and the metallurgical reason behind it. We start...
Heat treatment of powder metallurgy parts
The use of powder metallurgy (P/M) for the production of near-net shaped parts has increased in recent years due to performance gains, as well...
Safe operation of endothermic atmospheres
In the last column, we discussed the importance of making sure that the endothermic atmosphere was the right composition to ensure proper heat treatment....
Endothermic atmospheres used for heat treating
During heat treatment, the part experiences different temperature regimes (Figure 1). Atmospheres are used in heat treating to protect the part from scaling at...
Water in oil-based quenchants can be problematic
The continuing retirement of “old hands” in the heat treatment industry has a growing generation of operators, supervisors, and engineers not knowing the severe...
