Titanium supply chain for aerospace industry goes through Russia

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The terrible war in Ukraine and the subsequent sanctions imposed on many Russian organizations have raised questions about potential supply chain vulnerabilities. While Russia is primarily an exporter of resources such as oil, gas and metals, one market in which it is a dominant player is titanium and titanium forgings. Many people are becoming aware of the potential consequences of a longer-term stoppage of the flow of these critical materials.

Titanium and titanium alloys have unique properties: they are lightweight and have a very high strength-to-weight ratio. Their density is typically about 60% of that of steel. They withstand high temperatures and have a high resistance to corrosion. These properties have allowed the metal to be widely used in the aerospace industry, chemical processing vessels and piping, power plant components, desalination plants, and medical applications such as implants and surgical devices. Titanium alloys are also used in sports equipment such as golf club heads, bicycles, and winter sports equipment such as bobsleigh skates. Separately, titanium dioxide is the main pigment in white paint and it is also used in paper, plastics and cosmetics.

Titanium alloy forgings are particularly important in aerostructures and engines. Two particular characteristics of the metal make it particularly attractive for advanced composite aircraft like the Boeing 787 and the Airbus A350XWB. The first is that it is less likely to cause galvanic corrosion when joined to carbon fiber reinforced plastic (CFRP) parts like body and wing panels or control surfaces. Galvanic corrosion occurs when two dissimilar metals are connected together and electrons can flow through and cause the metals to corrode. The carbon fibers in CRFPs are electrically conductive, so attaching them to aluminum alloys makes both the metal and the composite vulnerable to deterioration. Titanium alloys resist this. The second interesting property is that the coefficients of thermal expansion of titanium are very similar to those of CFRPs. This is important because aircraft experience large temperature changes during normal flight cycles. Titanium alloys make up around 15% of the Boeing 787 airframe weight. In the Airbus A350XWB it is around 14% and is used in landing gear, pylons, props, door frames , frames and other parts.

Two ores, ilmenite and rutile, are the main sources of titanium, the former constituting 90% of production. The first step is to convert the ore into titanium sponge. The United States, Russia, Kazakhstan, UkraineJapan and China all produce titanium sponge.

VSMPO-AVISMA Corporation is the largest titanium producer in the world. It is located in Verkhnyaya Salda, Russia, about 1,800 km east of Moscow and about 550 km from the border with Kazakhstan. It produces a titanium sponge and transforms it into ingots. These ingots are in turn transformed into billets or slabs. Billets are made into a wide variety of shapes, including tubes, discs and rings, as well as forgings.

Titanium forging

Forging is a manufacturing process that strengthens metals. It uses compressive forces to align the metal grain structure with the shape of the part. Usually this is done at precise high temperatures, depending on the type of metal being worked on. Blacksmiths traditionally forge pieces by hammering heated metal on an anvil with a hammer. Large industrial parts are forged with huge presses that exert several tons of pressure or press the parts into compression dies. We reported a long time ago loss of forging ability in the United States for large metal parts as a critical deficiency.

Titanium alloys are difficult to forge; it is difficult to cast the metal in dies to obtain the desired shapes. Because titanium alloys are also difficult to machine, producers want to forge them into “near-sharp” shapes. that is to say, closer to the finished shape to minimize machining time and cost. Aerospace forgings, especially engine parts, must be ultra-reliable, so temperature and stress must be carefully controlled during the process.

Boeing has a Partnership with VSMPO, the Boeing-VSMPO Innovation Center, which was established in 2000. Boeing also established a joint venture, Ural Boeing Manufacturing, in 2009 at the VSMPO plant site. The JV opened a second site in 2018, specializing in rough machining of titanium forgings for all Boeing commercial programs including the 737 MAX, 787 and 777X.

VSMPO-AVISMA Provisions titanium forgings for the Airbus A350XWB via the Spanish company Aernnova Aerospace. Aernnova builds the tailplane in Getafe and Illescas in Spain and ships it to Toulouse, France, where the final assembly line is located. Aernnova supplies almost all other Airbus programs, as well as important components for Boeing’s 747-8, 787-9/10 and Dreamlifter programs.

In 2019, the United States imported 95% of the titanium it consumed. Iluka Resources closed its Former Hickory Mine in Virginia in 2016. Allegheny Technologies in slow motion its Rowley, Utah, titanium sponge plant in 2016 because it could buy imported material at a price below its domestic cost of production. And Timet, which operated the last National Titanium Sponge Plant in Henderson, Nevada, went through a collective licensing in 2020. All of these operations have come under cost pressure from foreign competition, as well as the slowdown in aerospace manufacturing that has accompanied the pandemic. The terrible situation in Ukraine and Russia will put a lot of pressure on titanium supply chains, and Boeing warned about it in January. With all the grim news coming out of this part of the world, this vulnerability has yet to receive widespread attention outside of the industry.

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