In the past, manufacturers with in-house heat treat have turned to hot isostatic pressing (HIP) technology to decrease porosity and increase densification in their processed parts. Now, in 2023, is there anything new HIP can offer heat treaters? To find out, Heat Treat Today asked seven HIP equipment suppliers and heat treat users to enlighten us on the world of HIP as it is today.
Enjoy this original content contribution, first released in Heat Treat Today's March 2023 Aerospace print edition!
What are the recent, cutting-edge developments in HIP?
Sales Engineer
Engineered Pressure Systems, Inc.
Source: EPSI
Matt Fitzpatrick, sales engineer at Engineered Pressure Systems, Inc., shares, “Self-diagnosing alarms, failures, and power as well as medium consumption savings are key developments in the HIP industry. Enhanced uniform cooling joins with the development of materials (ceramics, metals, insulation fibers) to improve equipment uptime and reduce cycle time. Self-diagnosing alarms may play a key role in HIP’s future. Each HIP control system has alarms to alert when parameters are not met. The future will be in determining why the parameters are not being achieved. For instance, future control systems may be able to diagnose a bad thermocouple, a failed motor solenoid valve, a leaking high pressure valve, etc.
“Unfortunately, there are not very many HIP systems purchased every year. It takes time to develop this technology. A good example would be the automotive industry: sensors tell technicians exactly where the problem in the vehicle is. As the PLCs and computers become more advanced, the specific software programs that are developed for the HIP system — in conjunction with advancements with sensors in motors, pumps, valves, transducers, meters, and components — will make it easier and less time consuming to develop complex troubleshooting programs.
“To some heat treaters, HIP can be an unnecessary evil, given its expensive, long cycle times. HIP, however, cannot be eliminated, because it is the only process that attains the densification required in the aerospace, medical, and high-performance automotive industries.”
Vice President
American Isostatic Presses, Inc.
Source: American Isostatic Presses, Inc.
“HIP technology is very mature and reliable,” Cliff Orcutt, VP of American Isostatic Presses, Inc. assures, “however, the cost to use the process is always one major hurdle preventing its use. AIP is working hard to develop lower cost equipment that can still maintain excellent results and bring higher pressure capabilities to the market. We are also expanding our footprint further into the toll HIP arena with similar goals of lower cost and faster turnaround services. Our new facility opening in Columbus, OH, this spring will also provide a world class development resource to help interested manufacturers determine whether the process can be applied to their parts.”
Applications Engineer
Quintus Technologies
Quintus Technologies’ Chad Beamer points to the versatility of HIP: “HIP continues to make its mark in many industries by offering a path to consolidate powders and eliminate process related defects for 100% pore and void free material for improved product integrity. With the continued demand for this special process, Quintus Technologies has several key developments driving industry growth due to the expanding functionality of the equipment. The voice of the client consistently demands production efficiency, reduced environmental impact, and improved process reliability. Modern HIP equipment is delivering on this front, creating a promising future for HIP.
“HIP systems equipped with rapid cooling and quenching functionality (URC®/URQ®) are facilitating lean manufacturing with increased productivity by shortening the cooling segment over conventional cooling, while also offering the opportunity to consolidate thermal post processing steps. HIP systems with URC® can cool at rates up to 932°F/min (500°C/min), and compact HIP units with URQ® furnaces are capable of cooling more than 5400°F/min (3,000°C/min). This leads to the opportunity to combine several thermal processing steps into one process performed under pressure. The combined, or integrated, heat treatment approach inside the HIP vessel is known as High Pressure Heat Treatment™ (HPHT™).
“Developments with the controllability of HIP are further expanding the use of HPHT. The cooling rate of the HIP can be steered using thermocouples to set the desired cooling rate from either process gas or component temperature feedback. Steered cooling driven by the component temperature is interesting when considering different thicknesses of parts in the HIP. The machine can therefore autonomously steer the temperature based on the thickest component to achieve desired material properties. See an example of steered cooling from component temperature feedback in the graph above.
“The tailoring of HIP cycles is a new area of development too. Due to the excellent controllability in a modern HIP tailored heating, sustaining, and cooling segments can be programmed and precisely executed. This is an area of interest for materials needing high cooling rates or having a tight tolerance on heating and cooling rate requirements. An excellent example of a tailored HIP cycle can be seen in recent work by Goel et al., at the University West in Sweden (see illustrations above), capturing the possibility to significantly reduce the treatment time for additively manufactured Inconel 718.
“Quintus has also been working to reduce discoloration and oxides on the surface of parts by improving equipment and best practice in terms of clean HIP operations. This is not an easy challenge to overcome. HIP is performed at very high pressures, often above 1000 atmospheres, using high purity Argon gas (>99.99x). Because of the need for additional gas volumes to achieve desired system pressure during regular HIP, the total pressure of contaminants can become high. Despite these challenges it is now possible to produce materials that have a high affinity for oxygen e.g., aluminum, titanium, and chromium, with significantly less oxidation. This can lead to improvement in fatigue and corrosion resistance fulfilling design criteria and gives great opportunities for more sustainable post-HIP.
“Developments with the digitalization of HIP equipment are also playing a role in meeting the demand of the Industry 4.0 mindset. Integration of the equipment into digitalized production lines enables product and process improvements. Digitalization of high-pressure equipment offers many benefits as it creates opportunities to streamline and save time with preventative maintenance tasks, provides valuable insights and trends into the health of the equipment, expands collaboration, improves uptime, and saves cost.”
Founder and CEO
HT-MX
“In 2023,” Humberto Ramos Fernández, founder and CEO of HT-MX, comments, “HT-MX will continue to establish itself as the main HIP supplier and expert in Latin America. Additionally, with our Honeywell Aerospace approval, we will be pursuing at least three more OEM approvals not only in the aerospace industry but medical and automotive as well.”
Marketing Manager
Paulo
Phil Harris, marketing manager at Paulo, highlights HIP’s customization: “The primary focus has been on providing customized HIP cycles that either deliver superior mechanical properties for customers or reduce the need for post-HIP to streamline the supply chain and speed up turnaround. We’ve been successful in both and are always looking for opportunities to collaborate on such endeavors.”
Marketing Manager
Aalberts surface technologies
Source: Aalberts surface technologies
Leah Tankersley, marketing manager, Aalberts surface technologies, says, “We added HIP services to our portfolio in 2020. We have two wire-wound HIP vessels, and plan to expand further with a third unit ready to ship from Sweden soon. Each unit boasts the latest HPHT technology. They are equipped with the proprietary Uniform Rapid Cooling (URC) feature. Our HIP technology has the ability to combine stress relief, HIP, solution, and age in a single process. HPHT HIP streamlines the steps involved in material densification and heat treatment. The URC feature enables all processed components to cool uniformly in a controlled environment, resulting in minimal thermal distortion and non-uniform grain growth.”
CEO
Stack Metallurgical Group
Source: Stack Metallurgical Group
Doug Puerta responds for Stack Metallurgical Group: “Stack has been active in supporting the advancement of HPHT. Our newest HIP unit, a Quintus QIH-122, includes Uniform Rapid Cooling (URC) technology which enables cooling rates equivalent to what we achieve with traditional gas quenching. This technology not only allows for improved productivity, but also enables the combination of a traditional HIP cycle with stress relieving solution annealing, or even aging, all in one HIP unit.”
In the next five years, what advancements should manufacturers with in-house heat treat operations expect from HIP technology?
“In terms of cycle times,” Matt Fitzpatrick of Engineered Pressure Systems, Inc. says, “HIP systems are limited by how fast materials can be heated and cooled. In the next five years, reduced maintenance, improvements with furnaces and heat shields, and faster cycle times will occur at both the materials and design levels.”
Cliff Orcutt, from American Isostatic Presses, Inc., sees globalization in HIP’s future, “We don’t expect much change other than to see it expanding into new geographic regions and being applied to more products. The main problem affecting our industry is not deficiencies in the HIP equipment or process, but rather how to use it beneficially in a profitable manner. In the next five years I think countries, such as India, will begin to implement it much more widely as the process becomes better known. As more companies implement it their competition must follow to stay on the same page.”
Chad Beamer, from Quintus Technologies, shares the optimistic outlook, “Quintus is witnessing significant growth potential for HPHT, including the addition of this post-process HIP and heat treatment strategy into industry standards. Also, the demand placed by many industries on surface cleanliness requirements to reduce oxidation and discoloration of sensitive material systems will help drive forward clean HIP techniques. These advancements along with delivering new and upgrading existing HIP equipment with machine digitalization will meet the current and future demands placed by the heat treat market and OEMs.”
And what about HIP in Mexico? Humberto Ramos Fernández of HT-MX responds, “Being located in Mexico, the main advances in HIP in our environment will be mostly geared towards near shoring manufacturing for high added value parts. HT-MX´s HIP service is just one example of a high tech and high complexity process being used in Chihuahua to manufacture high end products and thus we expect near shoring to bring in more opportunities for these kinds of parts to be manufactured and assembled in Chihuahua and Mexico.”
Leah Tankersley of Aalberts surface technologies, says, “As a provider of HIP services, we cannot speak to the advancements in HIP technology per se, but we are seeing material advancements and development of new alloys in AM. These advancements will impact HIP cycles and lead to development of more unique cycles for AM that differ from traditional cycles developed for castings. We’re also seeing ASTM International AM Center of Excellence Consortium members from the AM value stream come together to collaborate on standardization of requirements for AM materials data which includes post processing/hot isostatic pressing. We are one of the founding members of this consortium.
“Additionally, we are working with Quintus to beta test their remote assistance fi eld service support through AR equipment and technology.”
Doug Puerta, Stack Metallurgical Group, thinks, “In the next five years, I expect we’ll continue to see aerospace and medical OEMs evaluate and approve HPHT for additional combined-cycle applications. Ultimately, with span time being so important to our customers (and their customers), combining cycles and reducing span is a really big deal.”
What is the #1 thing manufacturers with in-house heat treaters should know about HIP technology right now?
Safety first, says Matt Fitzpatrick at Engineered Pressure Systems, Inc. (EPSI): “Good safety and maintenance programs and experienced operators and technicians are key to a successful HIP system. Confined space rules and regulations, oxygen monitoring, nondestructive testing (NDT) inspections of the vessel assembly components, good maintenance, and end-user HIP plant safety programs are key. Training is provided with every system regardless of whether it’s a HIP system, CIP system, or WIP system. Before delivering a system, EPSI offers training for safety, maintenance, system operation, controls, and system parameters. Then during installation and startup, training occurs. When startup is completed, we offer training at the client’s site. Generally, this is mutually agreed on during the contract phase and delivery.”
“There is not just one thing,” Cliff Orcutt of American Isostatic Presses, Inc. says, “because HIP has so many different applications. For instance, HIP can be used to heal castings, make parts directly from powders, diffusion bond materials together, or pressure infiltrate materials. HIP can be applied to metals, ceramics, composites, and even plastics. I guess really the number one thing they should know is how to contact a reputable HIP company that can provide the information and technology they require.”
Chad Beamer of Quintus Technologies points to HIP’s benefits for both end customers and heat treaters, “Modern HIP units differ significantly from conventional HIP units. The technology has advanced over the decades offering expanded functionality and improved performance. As for all production processes, lean manufacturing is key to improving product quality, minimizing costs, and maximizing productivity. Reducing waste and increasing throughput should always be a focus.
“The addition of modern HIP with HPHT capability and clean HIP functionality as part of the production chain are HIP advancements that will facilitate robust and lean processes through reduction of yield losses, logistics, and quality-related costs. This is not only of strong interest to heat treaters, but also to the end customers in several industries. And with a broad product line of compact, medium, and large HIP capabilities available, commercially in-sourcing the technology to complement other heat treat equipment is now feasible for many companies.”
Humberto Ramos Fernández speaks directly to in-house heat treaters, “In-house heat treaters must know that, although similar, HIP is not heat treatment. Various aspects of the process are similar but there is a learning curve that must be transitioned and experience in heat treat doesn’t necessarily automatically translate into the HIP experience.”
Aalberts’ Leah Tankersley plainly states, “HIP is an expensive investment.”
“Ironically,” says Doug Puerta of Stack Metallurgical Group, “One of the misconceptions is that modern HIP systems offer HPHT as an alternative to general heat treating. The intent of technology is for use when conventional HIP and heat treatment is required for a given application. When HIP is not required, heat treating is performed in a traditional vacuum furnace. The economics don’t really support heat treating in a HIP unit when a HIP segment is not included.”
How is HIP benefiting heat treaters in the industry today?
Matt Fitzpatrick, from Engineered Pressure Systems, Inc., says, “First, we employ heating and cooling software program models to help with cycle times, though cycle time generally depends on the material being processed.”
Fitzpatrick continues, “Loading and unloading a HIP cycle can be time consuming. We have developed tooling that helps operators prepare a HIP cycle and test the thermocouples prior to being loaded into the HIP vessel. In addition to reducing time, this tooling ensures that the load is prepared properly and won’t damage the furnace while it goes into the vessel.”
Cliff Orcutt, American Isostatic Presses, Inc., replies, “We have many clients that use our HIP systems to improve the properties of AM parts, as sintering alone has a limited upper range for density achievement. By utilizing HIP they are able to achieve near theoretical density and remove voids that can degrade performance or affect surface post finishing. In many cases when you have improvement in properties it can allow redesign with less material usage to improve cost efficiency and help the environment.”
Chad Beamer of Quintus Technologies explains, “HIP is a well-established process that has played a role in delivering advanced materials and components since the 1960s. Originally developed as a diffusion bonding process, its use has expanded to the densification of castings and additively manufactured components as well as the consolidation of powder to produce billets of material or complex near net shapes. Several industries benefit from its use today including aerospace, space, power generation, medical, oil and gas, and nuclear to name a few.
“The process offers several benefits related to material performance. One of the main demands for HIP is to eliminate process-related defects in materials for improvement in mechanical properties. Dynamic properties such as fatigue and creep performance are significantly improved, as is ductility and fracture toughness. The elimination of internal defects leads to reduced mechanical property scatter offering more predictive properties. The outcome can offer extension of a component’s lifecycle as well as potential weight-savings and cost reduction. Another benefit of HIP is for the enhancement of surface quality. The absence of internal defects provides a path to produce machined and polished surfaces free of surface connected imperfections for improvement in mechanical properties and corrosion resistance, as well as optical properties for aesthetically critical applications.
“For heat treat service providers there is motivation to invest in HIP capabilities as it provides a natural complement to existing heat treatment equipment often offering a one-stop shop at many facilities. It also broadens the availability and flexibility of HIP and HPHT services to the industry which is an exciting opportunity.
“As for an OEM’s decision to insource HIP, the benefits are broad. The capabilities of modern systems lead to significant reduction in the production cycle time, savings in overall handling and cost, especially with custom HIP cycles. It also provides a path to gain more control of processing techniques with the opportunity to develop novel approaches while improving control of the intellectual property that is developed.”
Humberto Ramos Fernández, HT-MX responds, “For high value parts, such as aerospace engine components, lead times mean money. Being able to reduce, by weeks, the turnaround time for HIP parts in Mexico means that working capital for these parts is significantly reduced allowing our customers to enjoy these savings.”
Paulo’s Phil Harris says, “HIP, in conjunction with customized cycles, is allowing our customers to deliver parts which were previously not possible. Specifically, the ability to meet material property requirements with additive parts. Where traditional HIP cycles (designed for castings) left them short of tensile requirements, we’ve been able to achieve the necessary properties, winning both of us more work in the process. This success in turn drives the adoption of additive manufacturing.”
Leah Tankersley, Aalberts surface technologies adds, “Our customers benefit from the latest HPHT HIP technology to improve the materials characteristics of their parts. HPHT HIP helps clients reach 100% theoretical density after HIP, improve
tensile strength, and improve creep rupture properties.
“Our URC technology allows clients to reduce lead times with the ability to combine stress relief, HIP, solution, and age into one cycle which saves time by reducing the number of individual process steps and handling of parts. If clients choose to not do stress relief in the HIP, stress relief can be done in the vacuum furnaces that are just 50 feet away from the HIP system in our facility.”
Stack Metallurgical Group’s Doug Puerta replies, “We’ve had the good fortune to introduce several of our clients to the benefits of HIP. While HIP has long been mandated in quality critical industries such as aerospace, orthopedic implant, and power generation, there are other applications where significant performance gains can be achieved through HIP.”
For more information, contact the experts:
Matt Fitzpatrick
Sales Engineer, Engineered Pressure Systems, Inc.
mattfi tzpatrick@epsi-highpressure.com
Cliff Orcutt
Vice President, American Isostatic Presses, Inc.
corcutt@aiphip.com
Chad Beamer
Applications Engineer, Quintus Technologies
chad.beamer@quintusteam.com
Humberto Ramos Fernández
CEO, HT-MX Heat Treating & HIPing
humberto@ht-mx.com
Phil Harris
Marketing Manager, Paulo
pharris@paulo.com
Leah Tankersley
Marketing Manager, Aalberts surface technologies
leah.tankersley@aalberts-st.us
Doug Puerta
CEO, Stack Metallurgical Group
DPuerta@stackmet.com
