When it comes to stainless steel material, the 348 grade is among the most popular options available for most fabrication projects.
In this guide, we will explore vital aspects about stainless steel grade 348. From properties, composition to applications, you will find all information you need right here.
Let’s dive right in.
What is SS348?
It’s a stainless steel grade that falls under 300 series austenitic stainless steel. Very often it is specified in environments where corrosion resistance and temperature stability is critical as compared to other steels due to the presence of chromium.
SS348 has columbium and tantalum that are stabilizers to increase intergranular corrosion resistance.
SS 348 Chemical Composition
Chemical Element | Quantity of Chemical Element in Austenitic Stainless Steel 348 (%) |
Chromium | 17.0-19.0 provides corrosion resistance and strength. |
Nickel | 9.0-13.0 to improve corrosion resistance, ductility and toughness. |
carbon | ≤ 0.0 its on low content to minimize intergranular
corrosion |
Niobium | 10x(C + N) to 1.0 stabilizes carbon to prevent sensitization |
Nitrogen | ≤ 0.10 increases strength and corrosion resistance |
Silicon | ≤ 0.75 improves oxidation resistance |
348 Stainless Steel Properties
Physical Properties
348 SS has a density of 7.93g/cm3 which is typical for austenitic stainless steels. Of course, this is common with most stainless steel types. You can also explore density of stainless steel.
Its melting point is slightly lower on a range of 1399- 1429 degrees than that of pure iron due to alloying elements. In case you want to compare the 348 with other grades, you can check this: melting point of stainless steel.
Besides, it has a thermal conductivity of 16.3w/M.k at 100 degrees Celsius that is lower than that of carbon steels. At the same time, the 348 SS has an electrical resistivity that is higher than that of carbon steel due to its alloying elements.
Mechanical Properties
348 stainless steel is popular for its unique mechanical properties. Among the key parameters to evaluate are the stainless steel grade tensile strength و yield strength.
On average, the stainless steel tensile strength is about 515-720MPa depending if the condition is annealed or cold-worked. On the other hand, the yield strength is 205MPa in annealed condition.
Furthermore, this material exhibits, excellent ductility of 40 %( minimum) in elongation at break. While it has a hardness of HRB 90-100 which varies slightly depending on heat treatment.
Thermal Properties
Has a thermal conductivity that is lower than that of carbon steel thus ensures thermal gradients are less severe reducing thermal stress.
Its co efficiency of thermal expansion that expands uniformly, important for dimensional stabilities in thermal cycling.
Retains strength and mechanical properties at high temperatures making it ideal for heat exchangers due to its high temperature stability.
Advantages of using 348 Stainless Steel
348 SS has various advantages due to its properties. It has a unique combination of corrosion resistance and high temperature performance makes it reliable, durable in demanding environments.
· Corrosion Resistance
348 SS is resistant to corrosion and rust when exposed in harsh environments. It also performs well in applications that require exposure to oxidizing agents.
· High Temperature Stability
It’s ideal for applications in heat exchangers and exhaust systems because it maintains its mechanical properties at elevated temperatures of up to 870 degrees.
· It is Durable
A combination of it having strength and its oxidation resistance properties makes it durable in demanding applications.
Fabricating 348 SS
You can make useful products by adopting suitable stainless steel fabrication techniques. There are many ways of fabricating stainless steel grade 348.
اللحام
348 SS is excellent in welding due to the presence of niobium that stabilizes the steel. This element prevents sensitization which improves resistance to intergranular corrosion after welding.
Machining
With the use of proper tools, machining 348 SS is manageable. 348 SS belongs to the austenitic stainless steel family where it possess excellent corrosion resistance and mechanical properties.
Additionally, the high toughness and relatively low thermal conductivity makes machining stainless steel grade 348 possible.
Heat Treatment
As an austenitic stainless steel, 348 SS doesn’t respond to traditional hardening by heat treatment but it can be annealed to improve performance. Proper heat treatment ensures the steel maintains good mechanical properties. The best part, it makes it suitable for high temperature applications and corrosive environments.
Hot Working
This is a critical process for shaping and forming materials intended for high temperature environment. By maintaining uniform heating, and proper cooling, the stainless steel grade retains excellent mechanical properties and oxidation resistance.
Cold Working
Strength, hardness and corrosion resistance are improved through cold working of 348 SS. This cold working involves shaping and hardening of 348 SS at room temperature reducing ductility.
Uses of Stainless Steel Grade 348
- Steel Structure
It is suitable for fabricating complex structures without compromising the material quality. These include architectural structures and components.
- Nuclear Applications
The material is a perfect choice for making many nuclear system parts and components. This is mainly attributed to the low levels of cobalt hence can be used in nuclear applications.
- Heat Exchanger System
You can use 348 SS for heat exchanger system. It is a perfect choice for heat exchangers and boilers due to its high temperature stability.
- Food Processing and Medical Industries
It’s essential in food processing industries and medical industries and marine applications due to its oxidation resistance property.
In cryogenic applications it is used in storage and transportation of containers for liquefied gases due to its ability to retain toughness and ductility at low temperatures.
FAQs
1. What is 348 Stainless Steel Equivalent?
348 SS is closely equivalent to 347 SS under EN/DIN standards. 348 SS is austenitic where it is stabilized with niobium to improve its resistance to intergranular corrosion.
The exact equivalent grade varies depending on the standards of different organizations.
2. What an average 348 Stainless Steel Price per Ton?
The most important aspect is to keep an eye on the commodity markets and industry reports for latest information on the material cost.
The specific pricing for 348 SS depends on the market demand and, raw material costs and the manufacturing process. However, the actual pricing for 348 SS is not readily available in the public sources.
خاتمة
348 SS is designed for high performance environment. It is an austenitic steel alloy that is stabilized with niobium which is key to excellent mechanical properties for 348 SS.
At KDM, we are a professional stainless steel fabrication company in China. For all your stainless steel parts, contact us now.