AEROSPACE HEAT TREAT

High-Temperature Box Furnace Sent to Military Defense Organization

L&L Medium Sized High Temperature Box Furnace

A government military defense organization, located in the southeastern United States, bought a medium-sized high-temperature box furnace for military ceramic composite development. It will also help with research and development for various other components.

The furnace, built by L&L Special Furnace Co., Inc., has a working zone of 24” wide by 18” high by 36” deep and is rated for continuous operating temperatures up to 2500°F (1371°C). It is equipped with silicon carbide heating elements for high temperature operation and sealed from the inside out for use with inert “blanketing gas."

This furnace is controlled by a Honeywell program control and corresponding overtemperature protection.

 

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Heat Treat Customers in Aerospace and Defense to Receive Vacuum Furnaces

Patrick McKenna, President and CEO, Ipsen

Nine furnaces were shipped to six states in America, Canada, and the United Kingdom this past July from an international supplier of heat treat equipment. This same supplier will be providing five vacuum furnaces to four customers within the aerospace, defense, and commercial heat-treating industries. The products are all uniquely designed to meet the customers' specific heat treating requirements.

The ability for the international supplier, Ipsen USA, to deliver these products reinforces their transition into  the Vacuum Center of Excellence within Ipsen.

Ipsen Vacuum Furnace (photo source: ipsenusa.com)

"Ipsen has worked with international operations teams for decades," said Patrick McKenna, president and CEO of Ipsen USA, "shipping equipment from the US to countries all over the world[...] With the identification of Ipsen USA as the Vacuum Center of Excellence, we can continue servicing those companies with the level of quality they expect and deserve."

(photo source: NASA on unsplash.com)

 

 

 

 

 

 

 

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American Aerospace Heat Treater Purchases Hybrid Technology

Super IQ® Gas Carburizing furnace from SECO/WARWICK Group

REX Heat Treat, a commercial heat treater specializing in the aerospace market, has bought and installed a hybrid model -- conventional and vacuum -- furnace system from a European supplier. This technology will allow the company to improve their through-hardening and carburizing capabilities alongside their legacy harden and temper furnaces, while using their existing loader, baskets and washing system.

REX Heat Treat has become the first company to install and commission this hybrid model called Super IQ® Gas Carburizing furnace from SECO/WARWICK Group. Designed to eliminate endogas, the furnace allows clean processing and can even achieve higher temperature carburizing to speed cycles and improve yields in certain steels in a clean and cool manner.

Jonathan Rex, General Manager, Rex Heat Treat (photo source: LinkedIn)

The technological advances," says Johnathan Rex, general manager at REX Heat Treat, "allow us to run at higher temperatures, vacuum carburize, and clean harden with no decarburizing effects. The fact that our existing systems fit perfectly with this new addition helps to minimize the overall investment and accelerate successful integration. We expect the Super IQ to reduce operating costs, improve safety, and enable more environmentally friendly processing."

(photo source: Ashim D'Silva at unsplash.com)

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Continuous Vacuum Furnace Sent to Aerospace Manufacturer

A North American based aerospace manufacturer will receive a continuous vacuum (CV) furnace with 10 bar pressure quench capabilities. The 4 position, 4 zone furnace is rated to 2400°F, and will work well in processing medium to high volume parts.

Gasbarre's Continuous Vacuum Furnace (photo source: Gasbarre Thermal Processing Systems)

The supplier, Gasbarre Thermal Processing, shares that the independent load and quench modules allow the heat module to hold temperature and vacuum, creating a pure environment. The extended heating element coverage is conducive for thorough temperature uniformity, and then only the workload is cooled in the isolated cooling chamber. Quick transference from the heat module to the cool module as well as fast quench capabilities will aid processing of medium to high volume parts.

(photo source: Rodrigo Rodriguez at unsplah.com)

 

 

 

 

 

 

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Heat Treating Oven Goes to Aerospace Product Manufacturer

A manufacturer of aerospace products will be receiving a new heat treating oven for processing parts in a reduced oxygen atmosphere, utilizing nitrogen. The oven is electrically heated, and will be operational at temperatures exceeding 1,000°F.

The electrically heated standard draw batch oven (SDB Series) is provided by Wisconsin Oven. The maximum continuous operating temperature of this electrically heated oven is 1,400°F and has the capability to operate at 230° F above ambient. The thermocouple uniformity survey (TUS) qualified temperature range is 800°F to 1,400°F.

Wisconsin Electric Oven (photo source: siovens.com)

Qualified work zone dimensions are 24” wide x 24” high x 48” deep. Overall chamber dimensions are 36” wide x 36” high x 60” deep. The construction of the walls and ceiling feature the “CAN” style construction with heavy plate exterior (1/2” thick oven front) and includes 4” of ceramic blanket, backed with 4” of 6-pound density, industrial board style insulation for a total wall thickness of 8". The interior ductwork and liner utilize 18 gauge 309 stainless steel.

(photo source: Kennedy Space Center on unplash.com)

 

 

 

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Annealing Furnace for Aerospace and Defense Manufacturer

A roller hearth tube annealing furnace was recently installed and commissioned at an aerospace and defense products manufacturer. This manufacturer fabricates the most critical precision tubular products, and the high temperature roller hearth furnace quench anneals superalloy tubing for their drawing operation.

(photo source: Abbott Furnace Company)

Additionally, the electrically heated furnace is atmosphere tight and is operated with an argon protective atmosphere. The high-speed roll drive quickly transfers the tubing from the furnace to the water-spray quench.

The furnace, provided by Abbott Furnace Company, allows the manufacturer to increase production, processing a greater number of tubes between tubing draws. “On a daily production basis," says Mr. George Ray, chairman of the manufacturing company, "the Abbott Furnace is 300% more efficient than the previous furnace.” He indicates that with the +/- 5 F furnace temperature uniformity and the uniform water spray, the new furnace also provides better uniformity of hardness than the retired furnace.

(photo source: Abbott Furnace Company)

 

 

 

 

 

 

 

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Precision Parts Heat Treater Expands Operations

Peters’ Heat Treating, Inc., a 40-year-old heat treating company that specializes in a variety of high tech heat treating processes, moved its headquarters into a newly expanded Meadville, Pennsylvania facility located in the western part of the state.

Ribbon Cutting with the Owners: Doug and Jackie Peters (founders), Diana Wilkosz (VP), and Andy Wilkosz (President)
(photo source: Peters' Heat Treating, Inc.)

Additionally, Peters' Heat Treating also announced two new lines of business: aluminum alloy processing and stainless steel black oxide. Vice President Diana Wilkosz shared in a recent interview, "We added these two new lines because of the growing demands from the automotive, aerospace, energy, and defense industries. We are also working on Nadcap certifications."

The company specializes in vacuum processing, atmosphere heat treating/integral batch quench processing, laser heat treating, aluminum alloy processing, carburizing, scale free aging/stress relieving, cryogenics, black oxide coating, induction processing, nitriding/FNC and the proprietary Nitreg nitriding processes.

After being in their original facility for 40 years, this expansion, that covers 32,000 square foot of manufacturing space, has provided them the opportunity to expand and update their vacuum line, provide room to add new vacuum furnaces, as well as increase their product offerings and continue to grow the now 60-employee business.

Ribbon Cutting with Meadville Managers (photo source: Peters' Heat Treating, Inc.)

“We are excited to consolidate our services and knowledge in a way that maintains our history and dedication to the local community and industry while providing us the runway for a successful future,” said Andy Wilkosz, newly named president in 2019 and son-in-law of founders Doug and Jackie Peters. “These current times are challenging, but we know our business and the country will persevere.”

In addition to Peters' Heat Treating, the family also co-owns Laser Hard, a robotic laser heat treating company.

“It’s been a pleasure to be a part of the local community and to help companies grow,” Doug Peters said. “Probably the thing I’m most proud of is the great people I’ve had the opportunity to work with. I’ve watched them buy houses and have children, and now their kids are having children.”

Plant Expansion (photo source: Peters' Heat Treating, Inc.)

 

To learn more about Laser Hard, listen to the Heat Treat Radio episode in which they are featured.

 

 

 

 

 

 

 

 

 

 

 

 

 

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AMS2750F: Expert Analysis

AMS2750F, a rewrite of the specification that covers pyrometric requirements for equipment used for the thermal processing of metallic materials, was released at the end of June. For this Technical Tuesday feature, Heat Treat Today asked a few experts in the aerospace industry to share their insights of this much anticipated revision that helps to better clarify issues with the previous revision. Specifically, Heat Treat Today wanted to know what they perceived to be the top 2-3 most important changes in revision F; what companies should do to prepare for these changes; and additional thoughts about the revision as it relates to aerospace heat treating.

Industry experts who contributed to this Original Content piece are Andrew Bassett, president, Aerospace Testing & Pyrometry, Inc., Jason Schulze, director of Technical Services; Special Process – Metallurgy, Conrad Kacsik Instrument Systems, Inc., Peter Sherwin, Global Business Development manager for Heat Treat, Eurotherm by Schneider Electric, Jim Oakes, president, Super Systems, Inc., and Doug Shuler, lead auditor, owner, Pyro Consulting LLC.


Andrew Bassett was on the subteam for AMS2750F as well as the previous revision AMS2750E and has been a member of AMEC and SAE Committee B since 2006. He shares some “inside baseball” background about this four year process, “The AMS2750F subteam utilized the Nadcap Pyrometry Reference Guide, the Nadcap Heat Treat Audit Advisories that pertained to Pyrometry, and the collective experience from the sub-team which dealt with the previous revision issues and problems. The AMS2750F sub-team had a broad range of backgrounds, with representatives from Boeing, Safran, Arconic, GeoCorp Inc, Nadcap-PRI, and Aerospace Testing & Pyrometry.”

What do you believe to be important changes in revision F?

Jason Schulze, Director of Technical Services; Special Process – Metallurgy, Conrad Kacsik Instrument Systems, Inc.

Jason Schulze comments on offsets saying, “Offsets have often been a confusing subject throughout the years. How they are applied, removed and documented has caused confusion and has been a source of Nadcap findings. With the changes to the offsets section of AMS2750 in the new revision, these issues will be greatly reduced. Offsets have now been split into two categories; correction offsets and modification offsets. It will be important for suppliers to understand and implement the new requirements as well as use the same verbiage as this will hopefully alleviate further confusion.”

Andrew Bassett, President, Aerospace Testing and Pyrometry

Andrew agrees this is an important change regarding the offsets and further clarifies, “A “Modification Offset” is when an instrument is purposely, either through electronic means or manual means, shifts the accuracy away from the nominal temperature. This is typically done to “center a temperature uniformity” that may be skewed in one direction or another. The modification offset, when used properly, will shift the temperature uniformity more towards the set point of the thermal processing equipment. A “Correction Offset” is used to bring the instrument back to the nominal temperature. As always, a well defined procedure will be required on how the “Correction Offset” and “Modification Offset” will be introduced into your system.”

One of the biggest changes that caused a lot of controversy was the restricted re-use of expendable test thermocouples,” Andrew notes. “The AMS2750F subteam provided studies and data that showed that there was considerable drift of certain types of base metals thermocouples, especially when it came to Type “K” thermocouples. The previous revision of AMS-2750 already had restrictions on these types, but after providing data of the drift of these thermocouples, the team felt further restrictions were required for Expendable Base Metal SAT & TUS Sensors. Section 3.1.7.3 describes the limitations of these type thermocouples. Types “M”, “T”, “K” & “E” shall be limited to 3 months or five uses, whichever occurs first between 500F and 1200F (260C and 650C) and is limited to single use above 1200F (650C). Types “J” and “N” shall be limited to 3 months or ten uses, whichever occurs first between 500F and 1200F (260C and 650C) and is limited to single use above 1200F (650C).”

Peter Sherwin, Global Business Development Manager for Heat Treat, Eurotherm by Schneider Electric

Peter Sherwin comments on instrumentation, “From an instrument perspective our no.1 focus is the instrument accuracy specification. This has not changed for Field Test or Control and Recording Instruments (now in Table 7), however the impact of the decimal place for digital recorders could cause some issues for less precise instrumentation. In 3.2.3.1 All control, recording and overtemp instruments shall be digital 2 years after release of AMS2750F – this was not a surprise, and today’s overall cost (paper, pens, storage etc.) of paper chart recorders cannot match their digital counterparts. Digital time synchronization (3.2.3.19) is also sensible to ensure you have an accurate time record across a number of Furnaces/Ovens and charts – we are used to this for other regulations (e.g. FDA 21 CFR Part 11) and offer a SNTP/Time Synchronization feature in our Recorders.”

Jim Oakes, President, Super Systems, Inc.

Jim Oakes shared his pleasure with section 3.2.3.12, “I was happy to see the document address integrated recording/controlling data.  It states in section 3.2.3.12 when the control and recording system is integrated such that the digitally displayed control value and digitally recorded value are generated from the same measurement circuit and cannot be different, it is only necessary to document a single displayed/recorded value for the control reading.  This is happening through direct communications, so what you see on the controller is what you are recording electronically.  This saves a step and eliminates the need for additional documentation.”

Doug Shuler, Lead Auditor, Owner, Pyro Consulting LLC

Doug Shuler cites the auditor advising piece, “The top of the list has to be the overall progress we made by incorporating auditor advisories and pyrometry reference guide FQS into the body of the specification so users don’t have to ask themselves “What did I miss.”

How should companies prepare for these changes?

Jason Schulze’s advice to companies focuses on training, “Companies should receive concise training regarding the revisions within AMS2750F, including administrative and technical. As with any training, continuous courses may be necessary to ensure comprehension. I recommend performing a characteristic accountability for each and every requirement stated within AMS2750F.”

Peter Sherwin encourages companies to ready instrumentation for the standards, “Recent feedback from the MTI indicated that 3rd party audits to the new standard would probably start next year. However, if you are in the market for a new instrument then it only makes sense to ensure this meets the requirements of the updated standard.”

Doug Shuler sees the benefit of analysis, “Users should prepare by performing an internal or perhaps an external gap analysis to establish where their pyrometry system is today, and what has to be changed going forward.  Users don’t have to wait until AMS2750F and AC7102/8 Rev A are released and in effect before making changes.  The key is that if a user has an audit before the revised Nadcap Checklist AC7102/8 Rev A becomes the law of the land, they will have to declare compliance to AMS2750E or AMS2750F in full and will be held to that revision’s requirements.  Once AC7102/8 Rev A takes effect (best guess after January 1, 2021)  all audits will be done to AMS2750F.”

Andrew Bassett recommends, “First and foremost, get a copy of AMS2750F and start the review process. Since the document was a complete re-write, there is no change summary or change bars to point the supplier in the direction of what has changed. Spend time creating a matrix of the previous requirements (AMS2750E) and comparing to the new requirements (AMS2750F). I would suggest breaking this matrix down into four main sections: Thermocouples, Calibrations, System Accuracy Testing, and Temperature Uniformity Surveys. This will allow suppliers to work on each section without getting overwhelmed by the entirety of the specification. Currently at the time of writing this, there is no formal implementation requirement for AMS2750F. Typically this will either be dictated by the suppliers’ customers, or in the case of Nadcap, they will issue a “Supplier Advisory” as to when their expectation for implementation will be.”

Final Thoughts

Planning for the future will serve companies well for the long term encourages Doug Shuler,  “With a number of significant changes, nearing a complete rewrite, now is a good time to take a look at your internal procedures that may have become fragmented over the years and streamline them to the new revision.  Auditing for Nadcap for over 10 years has shown me one thing for sure.  Those companies that have a thermocouple procedure, a calibration procedure, a SAT procedure, an alternate SAT procedure, a TUS procedure, and maybe even multiple TUS procedures for different kinds of furnaces (Air, Vacuum, Atmosphere, etc.)  usually have a more difficult time with audits because the SAT procedure also addresses thermocouples, but doesn’t address correction factors because that’s in the instrument calibration procedure… See where this is going?  Consider writing one pyrometry procedure with sections in it just like the specification.  Then, the SAT section can refer to the thermocouple section for test thermocouples and to the instrument section for test instruments, etc.  It’s like re-writing AMS2750, but customized for your facility, your equipment, and your practices.  In the end, remember that the pyrometry portion of your Nadcap audit follows my P.I.E. acronym.  Procedures that Include all requirements and Evidence to show compliance.”

Paying close attention to the right data solution will alleviate potential headaches when dealing with both the new AMS2750F revision and the CQI9 (V.4 update) says Peter Sherwin, “Many commercial heat treaters will also have to cope with the update to CQI9 Version 4 at the same time! According to the MTI, your ‘end’ customers may request you perform your self-audit to the new standard from this point forward. There is a bit more time allocated to move to digital (3 years), but my advice would be to take advantage of digital solutions sooner rather than later. The right data solution should save you money over time compared to the paper alternative.”

Finally, amidst all the new changes AMS 2750F has offered, Jim Oakes assures, “…the pyrometric requirements that most of us are used to will still be very familiar as this document becomes the new standard.”

 

(Photo source: pixabay.com)

 

 

 

 

 

 

 

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Process Innovation to Reduce Distortion During Gas Quenching

“High-pressure gas quenching (HPGQ) attempts to reduce temperature nonuniformities by reducing the cooling rate; however, this is generally not sufficient to eliminate shape change. Shape change can be predicted by heat treatment simulation software, but it is difficult to reproduce the exact same cooling conditions in the vessel for each batch. Therefore, the distortion of the components will not be consistent from batch to batch.”

Read the case study to see one response to this issue in this original content from Heat Treat Today by Justin Sims, lead engineer at DANTE Solutions.

This article first appeared in the latest edition (March 2020) of Heat Treat Today’s Aerospace Heat Treating magazine.


Distortion is generally described by a size change and a shape change. In heat treatment of steels, size change is unavoidable and is mainly due to the volumetric difference between the starting microstructural phase and the final microstructural phase. Shape change of steel parts from heat treatment is due to nonuniform thermal and nonuniform microstructural strains as a result of nonuniform cooling or heating, alloy segregation, poor support of the component while at high temperature, thermal expansion or contraction restrictions, or residual stresses from prior forming operations. Nonuniform cooling or heating can be as fundamental as the temperature gradient from the part surface to its core, or as complex as the flow of fluid around a component feature. Both can result in nonuniform strains, resulting in a shape change. If the stresses causing these strains exceed the yield strength of the material, then permanent shape change will occur. Size change can be anticipated and is predictable, while shape change, or distortion, is usually unanticipated and more difficult to predict.[1-2] 

Justin Sims,
Lead Engineer,
DANTE Solutions

Most thermal processes try to control these nonuniformities using methods of low complexity such as part orientation and rack design. Quenching systems, for example, are generally designed to remove as much thermal energy from the work pieces as possible and to do this as quickly as possible. High-pressure gas quenching (HPGQ) attempts to reduce temperature nonuniformities by reducing the cooling rate; however, this is generally not sufficient to eliminate shape change. Shape change can be predicted by heat treatment simulation software, but it is difficult to reproduce the exact same cooling conditions in the vessel for each batch. Therefore, the distortion of the components will not be consistent from batch to batch.

In response to this issue, a prototype gas quenching unit capable of controlling the temperature of the quench gas entering the quench chamber was devised. With the DANTE Controlled Gas Quench (DCGQ) unit, it is possible to have control of the thermal and transformation gradients in the component by controlling the temperature of the incoming quench gas, thereby significantly reducing, or eliminating entirely, the shape change caused by quenching. In doing so, the size change can easily be predicted by heat treatment simulation software, and post-hardening finishing operations can be reduced or eliminated. This process is ideal for thin parts or components with significant cross-sectional changes. Atmosphere Engineering (now part of United Process Controls) in Milwaukee, Wisconsin constructed the unit and provided the logic to control it. All experiments with the unit were conducted at Akron Steel Treating Company in Akron, Ohio. The project was funded by the U.S. Army Defense Directorate (ADD).

Figure 1 (left) shows the front of the unit, while Figure 1 (middle) shows the back of the unit. The back of the unit contains the human machine interface (HMI), shown in Figure 1 (right), where process parameters can be modified and DCGQ recipes entered. The prototype unit has a working zone of nine cubic ft. and is capable of quenching loads up to 100 lbs. at one atmosphere of pressure.

Figure 2. Comparison of quench gas temperature entering the
quench chamber versus the recipe setpoint temperature for
two different DCGQ process recipes

The ability of the unit to maintain continuity between the recipe setpoint temperature and the actual temperature entering the quench chamber is absolutely paramount. Figure 2 shows two schedules, one aggressive and one conservative, comparing the recipe setpoint (Chamber Inlet SP) to the actual quench gas temperature (Chamber Inlet PV). Figure 2 also shows that the prototype unit has good control of the quench gas temperature between 752°F (400°C) and room temperature, the martensite transformation range for most high hardenable steel alloys. There is some deviation between the two temperatures below 392°F (200°C) for the aggressive schedule as the setpoint reaches its set temperature, due to the relatively small temperature difference between the quench gas and the shop air. This small temperature difference makes it slightly difficult for the air-to-air heat exchanger used in the design to keep up with the rapid drop in temperature, but overall there is very good control of the quench gas temperature.

Figure 3. Micrograph of DCGQ (left) and HPGQ (right) processed coupons, mag. 1000X
There is a copper layer on the surface of the DCGQ processed coupon.

Microstructural examination was conducted on Ferrium C64 coupons processed using the DCGQ process and coupons processedusing a 2-bar HPGQ. C64 was chosen for this study due to its extremely high hardenability and its high tempering temperature. Figure 3 compares the microstructures of the two processes at a magnification of 1000X, and no significant difference is detected. The DCGQ coupons required two hours to complete the transformation, whereas the HPGQ coupons transformed in a few minutes. There is no indication that the slow rate of transformation damaged the microstructure or mechanical properties in any way. Tensile and Charpy properties were equivalent between the two processes.

Distortion coupons, thick disks with eccentric bores, were designed and manufactured with the goal of evaluating the distortion response when subjected to a DCGQ process, and then compared to coupons subjected to a standard 2-bar HPGQ operation. All coupons were manufactured from the same Ferrium C64 bar stock. All coupons were cryogenically treated and tempered at 595°C for eight hours after quenching.

Figure 4. Nomenclature and locations used for out-of-round measurements on the distortion coupon

Figure 4 shows a distortion coupon with the nomenclature and locations used for measuring the out-of-round distortion of the eccentric bore. Due to the uneven mass distribution, the north-south direction will generally be larger than the east-west direction. Five measurements were then made along the axis of the coupon using a Fowler Bore Gauge.

Table 1. Out-of-round distortion measurements of the distortion coupon for a DCGQ and HPGQ process

Table 1 shows the results from four coupons; two hardened using the DCGQ process and two processed using the standard 2 bar HPGQ for C64. The individual measurements (EW1, NS5, etc.) are relative and are dependent on the reference value used for the bore gauge. The individual measurements give an indication of the variation in distortion in the axial direction. The out-of-round measurements are actual values, as they are the difference between the actual measurements. The DCGQ process gave significantly less distortion than the HPGQ process.

While the values reported show a 50% reduction in out-of-round distortion for the DCGQ process, a larger gain could have been realized if two other conditions were addressed. First, the coupon for DCGQ was placed directly into a 1832°F (1000°C) preheated furnace since the prototype unit does not have austenitizing capabilities. Controlled heating, just like controlled cooling, should be utilized to realize the full potential of this process. Second, the DCGQ schedule was designed for another coupon geometry that was processed together with these distortion coupons. Therefore, the schedule was not optimum for this coupon geometry.

Table 2. DANTE simulation results comparing HPGQ and DCGQ using the experimental conditions and a DCGQ with optimized heating and cooling schedulesMARCH 2020

Table 2 compares the DCGQ simulation results in which the two processes executed on the experimental coupons were compared to an optimized process, including controlled heating and cooling schedules designed for this coupon. The optimized schedule predicts an order of magnitude reduction in out-of-round distortion. Comparison of the measurements from the HPGQ and DCGQ experiments in Table 1 to the model predictions in Table 2 shows that the model predictions agree closely with the experimental results.

Simulating the application of the DCGQ process to a gear geometry, the predicted warpage of a bevel gear was examined. The simulation looked at the differences between an oil quench, 10 bar HPGQ, and a 10 bar DCGQ process. From Figure 5, it is clear that the HPGQ process is predicted to produce the most distortion. Even though the 10 bar gas quench has a slower cooling rate than the oil quench, less distortion is not guaranteed since a slower rate does not guarantee a more uniform phase transformation.[3] In this case, both heating and cooling were controlled for the DCGQ simulation.

Figure 5. Comparison of oil quench, HPGQ, and DCGQ processes for a bevel gear

In summary, a prototype gas quenching unit has been constructed with the ability to accurately control the temperature of the quench gas entering the quench chamber. Experimental results have shown that mechanical properties and microstructure are equivalent between the DCGQ process and a 2-bar HPGQ process for Ferrium C64. Thick disks with eccentric bores were machined and then heat treated using DCGQ and HPGQ. It was shown that the DCGQ process reduced distortion in these disks by 50%. Simulation using DANTE then showed that the distortion could be reduced further if controlled heating and cooling are used. Finally, a comparison was made between an oil quench, HPGQ, and DCGQ processes for a bevel gear. This comparison showed that the HPGQ process was predicted to cause the most distortion. HTT

References

[1] Prabhudev, K.H., Handbook of Heat Treatment of Steels, Tata McGraw-Hill Publishing, 1988, p.111-114

[2] Sinha, Anil Kumar, ASM Handbook, Vol. 4: Heat Treating, ASM International, 1991, p.601-619

[3] Sims, Justin, Li Zhichao (Charlie), Ferguson B. Lynn, Causes of Distortion during High Pressure Gas Quenching Process of Steel Parts, Proceedings of the 30th ASM Heat Treating Society Conference, ASM International, 2019, p.228-236

 

About the Author: As an analyst of steel heat treat processes and an expert modeler of quench hardening processes, Justin Sims was the lead engineer for designing and building the DANTE Controlled Gas Quenching (DCGQ) prototype unit. This system was developed to minimize distortion of quenched parts made of high hardenability steels, while still achieving the required properties and performance.

For more information, contact Justin at DANTE Solutions

 

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International Aerospace Manufacturer Buys 2 Vacuum Furnaces

An international aerospace manufacturer orders two furnaces for its factories in the USA and Singapore. While both are single-chamber vacuum furnaces, they will serve different functions. One will be used for the heat treatment of exotic electrical steels, and the second will be used for annealing parts produced by 3D printing technology.

The furnace purchased for the heat treatment of exotic electrical steels has diffusion vacuum levels and a horizontal chamber. The chamber has the workload size of 24” x 24” x 36” and a 1300 lb. hearth capacity. Additionally, each furnace has a single-chamber, high pressure gas quench heat treat system adaptable to a wide variety of thermal processing applications including annealing, brazing, hardening, LPC and LPN, normalizing, solution heat treating, sintering and tempering.

Two SECO?WARWICK Vector Furnaces (photo source: SECO/WARWICK)

Each of the furnaces were bought from SECO/WARWICK Vector furnaces lines. This is the manufacturer's first purchase for a US installation from this supplier. The Vector furnaces lines are used in multiple applications within the aerospace sector, including heat treating turbine blades and landing gear, as well as in the aerospace aftermarket to maintain fleets of aircraft.

Maciej Korecki, Vice President of Vacuum Business Segment, SECO/WARWICK (photo source: SECO/WARWICK.com)

“SECO/WARWICK Group," commented Maciej Korecki, Vice President of Vacuum Business Segment at SECO/WARWICK, "has delivered hundreds of Vector heat treat systems worldwide, many of which are in steady use supporting the aircraft industry. We offer Vector with either a horizontal or vertical chamber depending on part configuration and the process needs of the customer, and we support each customer all over the world with a dedicated team of aftermarket professionals to keep them running at peak efficiency.”

Vector 3D builds upon the single-chamber vacuum furnace technology to combine the advantages of gas quenching capabilities with the growing requirements of the additive manufacturing market. The result allows customers to perform processes such as sintering, debinding, stress-relieving, aging or solution heat treatment, which are essential for the metal 3D printing sector. It has numerous applications in such industries as aerospace, automotive, medical and energy.

 

 

(photo source: NASA on unsplash.com)

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