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....
Lighter Weight and Increased Fatigue Strength with Adi
Have you ever hit a rock or other hard projectile while cutting your lawn? Have you noticed that the blade is dented, not broken...
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...
Temper embrittlement in steels
The use of small additions of molybdenum reduces the susceptibility of steels to TE. Temper embrittlement (TE) occurs in quenched and tempered steels that...
Furnace Maintenance
When a heat treat manager or anyone responsible for purchasing heat treating equipment makes a buy decision, they must first consider the process required,...
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...
Carburizing and Steel
In carburizing, gears must be heated to reach the appropriate temperature for the steel grade without causing excessive grain growth and distortion in a...
How did we get where we are today?
Having worked in the heat-treating industry for 58 years, I agreed in January 2011 to write a monthly column about all things heat-treating for...
Delta ferrite formation in fasteners
During the manufacture of fasteners, the formation of iron phosphide as delta ferrite can occur during heat treatment. This can have a deleterious effect...
Anatomy of a Heat-Treating System
Ninety-eight 600-pound trays are in continuous process, 13 are in the pre-process queue, nine preheating, 14 in the boost carb, eight in the diffusion...
Troubleshooting induction hardening problems: Part 1
Induction hardening is a unique method used to harden steels. The process uses a power supply, RF generator, induction coil, and quenching mechanism (spray...
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...
Aqueous inorganic salt quenchants
In this column, I will discuss the inorganic salt quenchants and how they can be used effectively to quench lean hardenability steel parts.
Often, a...
Transformation of austenite to pearlite
In this column, I will discuss the different types of precipitation hardening stainless steels and discuss their physical metallurgy.
Pearlite was named by Henry Howe...
Removing sludge from quench tanks
In this column, I will discuss the formation of sludge in a quench tank, its prevention, and removal.
Introduction
As a quench oil is used, it...
Heating with natural gas
It’s no secret that the heat treating industry is one of the major recipients of the impact when the U.S. Environmental Protection Agency (EPA)...
Heat Treatment of Titanium Alloys
Last month, I discussed the different types of titanium alloys. In this column, I will discuss the heat treatment of alpha and near alpha,...
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...
