Last year, California experienced the worst wildfires to date. (Source: Live Science)

It wasn’t just wildfires. The fire that broke out in Grenfell Tower in West London last June claimed 71 lives and sparked a public outcry for stricter building regulations around fire safety. The material used as cladding to wrap the outer part of the building came under scrutiny as it was extremely flammable and contributed to the rapid spread of the flames.

To prevent further disasters, architects, builders and policymakers need to reexamine the materials that go into building people’s homes, workplaces and public facilities.

Materials Matter

Steel is one of the most popular materials for construction as it is 100 percent recyclable, cost-effective and easy to work with. Moreover, World Steel Association’s Steel Construction Fact Sheet shows that steel is the most-researched and best-understood construction material available today. Its inherent characteristics and widely-available reinforcement options make steel the safest construction material for fire resistance.

eel is one of the strongest construction materials under high heat. (Source: CIC)

Fire resistance refers to the duration of time a building can withstand the load of the building, limit the passage of flames and gases and insulate the building against rising temperatures during a fire.

Steel is considered to be a fire-resistant material because it can retain all of its strength in temperatures up to 370ºC (700ºF). At 500ºC (930ºF), it loses 30 percent of its strength and at temperatures above 538ºC (1000ºF), unprotected steel loses close to half of its strength.

To put things into perspective, aluminum starts to decrease in strength when temperatures rise above 100ºC (212ºF), and at 204ºC (400ºF), aluminum loses 60 percent of its strength. Copper also loses 25 percent of its strength at 204ºC (400ºF).

Putting Materials to the Test

Darchem Engineering conducted the first-ever fire-resistance test in 1990 comparing galvanized steel, stainless steel, aluminum and fiberglass. Each material was exposed to temperatures from 1000 to 1050ºC (1832 to 1922ºF) for a period of 5 minutes. Both types of steel passed with minimal damage, while aluminum collapsed after 26 seconds, and fiberglass collapsed almost immediately.

Fire-resistance tests show that stainless steel is one of the most fire-resistant materials available. (Source: Applus)

They also conducted a 2-hour test with the same materials exposed to temperatures from 552 to 555ºC (1026 to 1032ºF). For stainless steel, the testing time was extended to 3 hours and it still had the least amount of damage out of all the materials. Galvanized steel passed the 2-hour mark, but did produce some molten zinc. Aluminum failed after 12 minutes, while fiberglass gave out in 6 minutes.

The results showed that steel, especially stainless steel, is the most fire-resistant material. However, one can never be safe enough when it comes to fire safety, and there are several ways to increase the fire resistance of steel that fall into 3 major categories.

Passive Fire Protection

Passive fire protection methods include boards, sprays and films that insulate the steel surface or structure against high temperatures. Fire protection boards are the most common type of passive fire protection as they can be customized and designed to fit the interior of the building. However, they are quite labor-intensive and costly compared to other options.

Boards are the most common types of passive fire protection. (Source: IPCOM)

Active Fire Protection

Active fire protection refers to any automatic or manual measure that can be taken to detect or fight fires. These include water sprinkler systems, alarms, smoke detectors, first responders and more. With advancements in AI and smart sensors, active fire protection will see vast improvements in the years to come and software systems will likely play a great role in fire prevention and protection.

The majority of active fire protection measures will become automated. (Source: Frontier Fire)

Intumescent fire protection

Intumescent fire protection includes paint-like substances that swell up in high temperatures and act as insulation against the heat. Typically, the intumescent substance will become 50 times thicker than its original state at about 200-250°C, well before steel undergoes any structural damage. Recently, intumescent paints have become much more prominent than passive types of fire protection as they are cost-effective, and can be applied on and off-site saving builders time and money.

Most recently, scientists and engineers from Nanyang Technological University (NTU) and national industrial developer JTC Corporation came up with a new intumescent fire protection paint called Firoshield. It is much cheaper than other types of intumescent paint and takes half the time to apply. The innovation will allow steel buildings to maintain its structural integrity for 2 hours with only 5 layers of paint, compared to the 15 layers required by other paints. 

Such innovations are expected to reinforce the safety of steel buildings, giving people more time for evacuation and limiting the spread of smoke and flames. On a final note, the fire-resistant qualities of steel should be taken into consideration not only for building frames and exteriors, but also for staircases, doors and other parts of a building that must stay intact for safe evacuations as well as for the safety of first responders.

However, like any other material, it has its limits. Corrosion is a common issue that affects iron’s durability, and environmental factors such as salt and pollution can cause further harm to the metal’s overall state.

To combat this, POSCO has created a specialized galvanized steel called PosMAC (POSCO Magnesium Alloy Coating Product), which is guaranteed to last five to ten times longer than standard steel due to its newly formulated composition.

PosMAC’s Unique Qualities

Galvanized steel has a special coating created from zinc that protects it from rust over time due to contaminants in the air. Yet, it still remains susceptible to corrosion — the primary zinc layer can easily be broken down, and potentially create more damage to the iron.

PosMAC, however, has an outer layer made from a combination of zinc, aluminum and magnesium that allows it to outlast galvanized steel’s zinc-only layer.

This mixture creates a protective film layer called simonkolleite when PosMAC’s coating is exposed. Simonkolleite is a stable compound that forms from the presence of magnesium, which then turns into an extra barrier of protection on top of its external layer.

PosMAC’s special coating also has a greater hardness than that of other steels, which reduces contamination during processing and minimizes the incurrence of scratches.

But the most remarkable aspect of simonkolleite is how it “heals” exposed parts of steel. Usually, when a surface is exposed, rust forms. However, with PosMAC, the simonkolleite layer gradually coats the vulnerable portion to prevent it from further corroding.

The Uses of Specialized Steel

Why is a highly corrosion-resistant steel like PosMAC considered so important? Because of its ability to withstand rust, it is considered a versatile material for painting, welding, construction processes and even raising livestock – all processes that require a lasting and high-strength metal to support prolonged usage.

It is ideal for manufacturing electronics and for automotive uses, and since it can survive high temperatures and environments with high moisture levels, it can be utilized in structures such as marine farms and subways.

Affordably Effective

PosMAC is considered cost-effective because of its high durability – with less corrosion, less is spent on maintenance and replacement fees. It also does not require a post-coating process like unplated steel, which also shaves costs.

Solar panels have become an important area where the use of specialized steel, such as PosMAC, is necessary. These renewable energy sources require stable structures that can last beyond 20 to 30 years, and as a result, are expensive to build. PosMAC ensures longevity, which saves money in the long run.

A New Rendition of POSCO Steel

PosMAC is one of the many examples that showcase POSCO’s status as a company creating premium and innovative products for the global market. The company has been named as the “World’s Most Competitive Steel Company” for 7 consecutive years, and continues to supply the world with high-quality steel to run a wide span of industries.

Thanks to PosMAC, POSCO’s reliable and corrosion-resistant steel solution, the standard face of steel has been revolutionized for the overall betterment of infrastructure and commerce.

PosMAC Shines at Renewable Energy India 2016, Asia’s Largest Energy Trade Expo

PosMAC: The Revolutionary Steel

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POSCO-America TSC (Technical Service Center) is strengthening its technical services and solution-based marketing support for its US and Mexican clients. The company opened last year with two offices in Mexico City, the capital and largest city in Mexico; and Birmingham, Alabama. Past January, it opened one more place of business in Houston, Texas. Based in these three cities, POSCO-America TSC is engaging in technical services and EVI (Early Vendor Involvement) activities for its clients in North and Central America, in which automotive and energy steel products are in high demand. Mexico is a global automotive industry hub. World’s top-notch automakers such as Nissan, GM and Volkswagen have active business operations in the country.

POSCO-America TSC Mexico City is currently focusing on automotive industry, providing technical services while working hard to develop new clients. It is also pursuing a certificate in automotive steel products. In an effort to increase the sales of steel products produced by POSCO and its local sales unit, POSCO-Mexico, the company is exchanging information with local processing centers and distribution corporations. POSCO-America TSC is scheduled to open a new business operation in Detroit, Michigan, within this year. Many global automobile manufacturers have headquarters and R&D centers in the city. Once it is opened, the Detroit office will dedicate itself to providing technical services for car companies in North America, as POSCO-America TSC Birmingham does.

Houston along with Scotland’s Aberdeen are two of the global energy industry hubs.  Located in Houston are companies from various sectors of the energy industry, such as Exxon Mobil, Shell, EPC (Engineering, Procurement & Construction) corporations and equipment fabricators. For this reason, POSCO-America TSC Houston is striving to get information about new business opportunities, by engaging closely with its key clients. As a result of all these efforts, POSCO-America TSC successfully signed a contract to supply GI (galvanized steel) products to a major US truck maker. Upon hearing that the GI materials the truck maker had been supplied were often flawed, POSCO-America TSC proposed a solution, in an effort to win trust from the company (and it worked perfectly!). The employees of POSCO-America TSC Mexico City demonstrate a high level of satisfaction with their everyday lives, due much to mild climate and friendly locals.

In addition, they take a great pride in representing POSCO’s automotive and energy steel business in the country with great growth potential. Living up to the motto, ‘POSCO the Great’, all the employees of POSCO-America TSC will enhance its efforts to provide its clients with upgraded technical services and solution-based marketing support. In addition to pursuing a certificate in automotive steel products, POSCO-America TSC will seek to strengthen partnership with key clients through more frequent contact with them. The company also plans to form a consultative group with local manufacturers, to improve the quality of its products.