A Cleveland-based heat treatment software and engineering firm, specializing in metallurgical process engineering and thermal/stress analysis of metal parts, recently announced that mechanical and fatigue testing is underway on an innovative gas quenching unit designed to minimize component distortion during the hardening process.
The DANTE Controlled Gas Quenching (DCGQ) unit is capable of quenching single components following a time-temperature schedule designed for a specific component and steel alloy using the DANTE software.
DANTE Solutions proposed the concept of the process and the DANTE Controlled Gas Quench (DCGQ) unit and collaborated with Milwaukee-based Atmosphere Engineering (now part of United Process Controls), which built the unit, and Akron Steel Treating. The project is funded by the US Army Defense Directorate (ADD), and the aim market is aerospace, where high hardenability steels are used for gears, bearings, and shafts.
According to Justin Sims, a mechanical engineer with DANTE Solutions, the project began with Phase 1, wherein the team had to “make sure that a relatively slow cooling rate through the martensite transformation did not degrade material properties.”
“Phase 1 showed that we had comparable results for hardness, tensile properties, Charpy impact properties, and bending fatigue to the standard quenching practice for Ferrium C64,” said Sims. “We then initiated Phase 2 and had a unit built that was capable of controlling the temperature of the incoming quench gas to within +/- 5°C.” Phase 2 will end December 2018 after two years. The Phase 1 process currently has a patent pending.
Mechanical & Fatigue testing is currently underway at Akron Steel Treating Company where the unit is installed, and samples have been processed to compare the DCGQ process to standard HPGQ of high alloy steels. The current steel under investigation is Ferrium C64. Sims noted that DANTE is overseeing the processing of the test materials, and commercial metallurgical testing companies are performing the tests.
Tensile Testing Metallurgical Laboratory completed the hardness, tensile and Charpy impact testing, and the results are similar for conventionally hardened C64 samples and DCGQ processed samples. IMR Test Labs is conducting the bending fatigue tests. The US Army at Fort Eustis will conduct the rolling contact fatigue tests.
“We have hardness, tensile, and Charpy impact results from the unit we can share with anyone who is interested,” said Sims. “Distortion, bending fatigue, and rolling contact fatigue are currently being evaluated and the results will be available before the end of 2018.”
“We believe that the DANTE Controlled Gas Quench (DCGQ) process, patent pending, has the potential to change the way heat treating is performed on high hardenability steels,” added Sims. “By controlling the temperature of the incoming quench gas, components experience a near uniform transformation to martensite. This near-uniform transformation has the potential to eliminate post-heat treatment correction operations by minimizing part distortion and allowing designers to account for the size change distortion in the initial design of a component. To date, mechanical and dynamic properties for Ferrium C64 processed using the standard hardening process and the DCGQ process has been identical. Bend fatigue and rolling contact fatigue are currently being evaluated.”
All images provided by DANTE Solutions.
