High Temperature Resistance

What is the key reason behind the popularity of stainless steel products in the market? Most commonly, it is used extensively across the global platform due to its high temperature resistance. And along with that, it is also used for its corrosion resistance. Sustaining the impact of high temperatures during manufacturing happens to be the main reason for its multiple applications. 

You might have used stainless steel products in multiple sectors due to their high-temperature oxidation resistance. It also chiefly demonstrates high-temperature strength, which is also beneficial for manufacturing processes. The high chromium content of stainless steel products is responsible for high temperature strength and wet corrosion resistance. 

Scaling Resistance

Scaling or resistance to oxidation is entirely dependent on the stainless steel product’s chromium content. It is pretty similar to that of corrosion resistance. Most of the austenitic steels come with at least 18% chromium contents. And that makes them ideal to be used at temperatures relatively higher till 870°C. 

In the grades like 309, 2111HTR, and 310, the resistance towards temperatures seems to be relatively higher than the rest. However, most of the martensitic and ferritic steels do not showcase such high temperature resistance. Instead, they have lower oxidation resistance and hence are not ideal for sustaining the harsh impacts of high temperatures.

But do you know, you have an exception here. The ferritic grade 446 comes with 24% chromium content, effectively used for resisting scaling at temperatures as high as 1100°C.

Creep Strength

What is creep strength? Well, it is the strength demonstrated by many materials towards the application of high temperature. It refers to the ability of the material to resist any sort of distortion while being exposed to higher temperatures for longer durations. In this case, the ones that require a special mention are none other than austenitic stainless steel.

The low carbon versions of the regular austenitic grades like 316L and304L are available with reduced strength even at higher temperatures. Therefore, these do not find appropriate applications for structural manufacturing processes at elevated temperatures. If you need to analyse the resistance of stainless steel, you can refer to the services of Maven Stainless Steel and get some professional guidance.

Now, remember that the ones that are available with “H” versions are the ones that come with high carbon contents. Therefore, these would demonstrate moderately higher creep strength, unlike the previous ones. 

Structural Stability

Do you know that there is a substantial problem with grain boundary carbide precipitation when stainless steel products are exposed to temperatures as high as 815°C? It probably results in a sharp reduction in the corrosion resistance of the material. 

And hence, this problem needs special mention as it can also affect the high temperature stainless steel resistance. And if you aim to eliminate this issue, try not using the “L” grades or low carbon ones available in the market.

There is another problem related to the resistance to high temperatures. The formation of the sigma phase tends to depend on both temperatures as well as time. And it seems to be quite different for each type of steel. 

However, it seems like Grade 304 is practically pretty immune to the sigma phase formation. Conversely, it doesn’t apply to the grades which come with high chromium and molybdenum contents. If the stainless steel variety has higher silicon content, it might not be immune to the sigma phase formation.

Therefore, if you expose these varieties for prolonged durations to high temperatures from 590 till 870°C, they would result in sigma phase formation. It refers to the precipitation within the steel microstructure which occurs due to exposure to such high temperatures. It can also lead to a brittle fracture, which might be practically challenging to get back to the previous condition.

Environmental Factors

Do you wish to know more about the vital factors for using stainless steel for high-temperature applications? The ones governing stainless steel resistance are sulfidation resistance and carburisation. 

How? The sulfur-containing gases can accelerate the attack on stainless steel alloys that come with high nickel content. And hence, in many cases, the experts prefer grades with lower nickel content or completely a nickel-free alloy. If you have the presence of sulfur-bearing gases, make sure to run the pilot test to determine the quality of the best alloy. 

Thermal Expansion

Another property that deserves special mention here is the thermal expansion of stainless steel. Generally, this property is expressed in the units of proportional length change for every degree increment in the temperature. 

If you want to understand the key points governing stainless steel resistance, know about the effect of thermal expansion. It is pretty noticeable where the stainless steel components are restrained, and the expansion might end up in bending and buckling. 

Sometimes, problems arise when the two dissimilar metals are fabricated together and thereby exposed to high temperatures. Also, the high thermal expansion rates in most of the austenitic stainless steels can highlight the fabrications similar to that of the low alloy steels. 

Even the non-austenitic grade stainless steels have higher thermal conductivities. It offers you considerable advantages in multiple manufacturing applications. Even the localised stresses resulting due to the expansion can contribute to the stress corrosion cracking. However, that would not attack the metal in usual conditions. 

Therefore, it is essential to minimise the adverse effects of temperature differentials in such scenarios to permit movement without any distortion. It can also help you avoid the formation of notches and any abrupt modifications in the sections within the material.

Final Takeaway

Do you want to find a reliable partner that can offer you the best resistance of stainless steel for manufacturing purposes? If yes, check out the services and products available at Maven Stainless Steel. From welded pipes and tubes to capsule tubes and PVD coated stainless steel, you can get all varieties and forms of stainless steel here. 

The company never makes any compromises with the quality of its services and products. They aim to deliver you only superior quality products at pocket-friendly prices. With a great dedicated team of experts, this company strives to fulfil all critical stainless steel requirements of their clients within strict deadlines. Do not wait anymore to get the best stainless steel products from Maven!