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FEATURE A D V A N C E D M A T E R I A L S & P R O C E S S E S | N O V E M B E R / D E C E M B E R 2 0 2 1 4 5 CONCLUSIONS The DANTE controlled gas quenching (DCGQ) process has the potential to handle difficult-to-quench part geom- etries without the use of expensive press quench tooling and reduce the amount of post-heat treatment processing required. The work presented here concluded that it is possible to control the temperature of quench gas enter- ing a quench vessel, at atmospheric pressure, in order to follow a time-temperature recipe required to control the martensitic transformation rate in high hardenability steel alloys. The prototype unit constructed was able to achieve great control within the temperature range of 400 to 100°C, using varying rates of temperature change. Figure 9 shows the microstructure, magnified 1000X, of a carburized (a) DCGQ processed coupon and (b) HPGQ processed coupon. As with previous experiments, there is no discernable difference between the two microstruc- tures. ~HTPro Note: Part II of this series will describe materials testing, microstructural evaluation, mechanical testing, and resid- ual stress and distortion. For more information: Justin Sims, senior engineer, DANTE Solutions Inc., 7261 Engle Rd. Ste. 105, Cleveland, OH 44130-3479, 440.234.8477, justin.sims@dante-solu- tions.com , dantesolutions.com . Acknowledgments The authors wish to acknowledge the U.S. Army Com- bat Capabilities Development Command Aviation & Missile Center (DEVCOM AvMC) for their support of this work. The authors also wish to acknowledge Solar Atmospheres for heat treating the experimental coupons using LPC and HPGQ, Akron Steel Treating for hosting the prototype DCGQ unit and conducting the experiments using DCGQ, and Tensile Testing Metallurgical Laboratory for mechan- ical property testing. References 1. G.E. Totten, C.E. Bates, N.A. Clinton, Handbook of Quenchants and Quenching Technology, ASM Interna- tional, 1993. 2. H.E. Boyer (Ed.), Quenching and Control of Distortion. ASM International, p 12-15, 1988. 3. A.L. Banka, B.L. Ferguson, D.S. MacKenzie, Evaluation of Flow Fields and Orientation Effects Around Ring Geometries During Quenching, Proc. ASM Heat Treating Society Conference, 2011. 4. N.I. Kobasko, M.A. Aronov, B.L. Ferguson, Z. Li, Local Film Boiling and its Impact on Distortion of Spur Gears During Batch Quenching, Materials Performance and Characterization, 1 (1), p 1-15, 2012. 5. D.S. MacKenzie, B.L. Ferguson, Z. Li, Effect of Quenching Variables on the Residual Stress and Distortion of a Heat Treated Disk, Proc. ASM Heat Treating Society Conference, 2005. 6. Z. Li, B.L. Ferguson, Gas Quenching Process Optimization to Minimize Distortion of a Thin-Wall Ring Gear by Simulation, HTM Journal of Heat Treatment and Materials, 68 (1), p 35-41, 2013. 7. Z. Li, J. Sims, B.L. Ferguson, J. Fetty, T. Baker, Minimizing Distortion During High Pressure Gas Quenching Processes, Proc. AHS International 74th Annual Forum and Technology Display, 2018. 11