This article by Thomas Hart in Gear Solutions magazine describes a new technique in heat treatment that can improve aerospace manufacture. It is derived from a paper that was first presented in November 2021 at the AGMA Fall Technical meeting.
We all know that the aerospace industry must work to the most exacting of standards. Maximum efficiency has to be achieved at the lowest possible weight. Strength is also essential as the parts have to operate in the harshest of environments.
Although there have been many material advances to meet these needs the heat treatment industry has remained virtually unchanged. Until now.
The quenching chamber is where the latest advancement in heat treatment can be found with a technique called 4DQuench (4DQ). It can be used to control one of the biggest issues in aerospace manufacture – distortion during the heat treatment process.
4DQ provides significant improvements to the quenching room process, providing full control of the speed heat is removed from the geometric area. The quenching process can be designed rather than relying on guesswork and experience. This type of control allows for homogenous cooling of the entire process.
With 4DQ, the gear bearing is rotated during the cooling process as the cooling gas passes over the component creating a contoured cooling profile around all desired surfaces. Combining the 3D flow from the nozzle manifold and the 1D of part rotation, you have a 4D quenched component.
4DQ is flexible, modular and can be used in many heat treatment applications. It is environmentally friendly and a low-cost solution for extremely high-quality output. 4DQ provides controlled cooling giving predictable results with minimal distortions.
Find a fuller account of the paper and 4DQ method here.