Do you need help to choose between 316L and 316 stainless steel when choosing your next project? I can understand your concern. If you are responsible for product development or procurement, your selected materials can make or break a project’s success.
316 and 316L are excellent options for high corrosion resistance, especially in acidic environments. Their main difference is their carbon content. This affects their corrosion resistance and welding properties to some degree.
Why should you continue reading? You will learn the subtle differences between these two grades to make an educated decision based on your needs.
What is the difference between 316 vs 316L Stainless Steel?
Stainless Steel: A Brief Introduction
Let’s begin with the basics. What is stainless steel, exactly? It is an iron-based metal alloy that contains at least 10.5% chromium. The chromium is a protective coating that gives the material its corrosion resistance. Stainless steel is ubiquitous and has applications in many industries, from cutlery to aerospace.
Stainless Steel 316 vs 316L Stainless Steel: What are they?
Why are 316L and 316 so significant? The molybdenum in both grades further increases their corrosion resistance. Engineers often use these materials in harsh environments like chemical plants or marine applications.
The Article’s Purpose
This article will explain the differences between 316L and 316 stainless steel. You’ll know by the end which material is best for your project. Let’s get started.
History
Discovering Stainless Steel
Turn back the time for a minute. It was in the early 20th Century that stainless steel first appeared. It was a new alloy that resists rust. This discovery revolutionized multiple industries.
Origin of 316 vs 316L Stainless Steel Types
These types of stainless steel are austenitic and belong to the 300 series. Researchers developed these types to offer better corrosion resistance. They also added molybdenum to the composition. Subsequently, they created the 316L version with low carbon content to enhance its weldability.
Primary Properties of Stainless Steel
Corrosion resistance
The resistance of stainless steel to corrosion is one of its significant benefits. The alloy’s chromium forms a protective coating, making it perfect for applications that could cause decay.
Strength and Durability
The mechanical strength of stainless steel makes it ideal for heavy-duty uses.
Aesthetic Qualities
Stainless steel’s sleek, modern appearance is also a reason for its widespread use. This material is versatile; you can use it in kitchens and car exhaust systems.
Classifying Stainless Steel – The Importance Of Type
Austenitic Stainless Steels
Austenitic steels like 316L and 316 are non-magnetic and offer excellent corrosion resistance and formability. They are ideal for kitchenware, chemical containers, and other applications.
Ferritic Stainless steels
Ferritic steels contain less nickel, and they are magnetic. Austenitic steels are better for decorative trims but don’t withstand stress.
Martensitic Stainless Steels
Martensitic Steels are more robust but have a lower corrosion resistance. Manufacturers use them to make surgical instruments and cutlery.
Definition of 316 Stainless Steel
Chemical Composition
316 Stainless Steel is composed of approximately 16-18% chromium and 10-14% Nickel, with a balance of iron. Its composition makes it resistant to corrosive substances.
Common Applications
You can use this grade in various applications, such as marine environments, chemical settings, and kitchen appliances. This is the grade you’ll find in high-demand environments.
Benefits and Limitations
The benefits are many, from corrosion resistance to durability at high temperatures. Its limitations include cost and a slight reduction in strength when compared with other high-strength alloys.
Carbon content is a crucial difference：316 vs 316L
Understanding Carbon’s role in Stainless Steel
Carbon is a relatively small part of the stainless steel chemical composition but has a significant impact. I contribute to overall strength and hardness. Carbon levels higher than a certain level can make the material less pliable and more prone to corrosion.
Comparison of Carbon Content between 316 vs 316L
Here is a simple comparison. Carbon content in 316 stainless steel can reach up to 0.08%, while 316L is limited to 0.03%. This subtle difference is what sets them apart, especially when welding.
Carbon content and performance
Weldability
The lower carbon content of 316L makes it an ideal candidate for welded structures. This reduces the chance of carbide precipitation occurring during the welding process and maintains its corrosion resistance.
Strengthening Your Body
Carbon content is a factor that may increase tensile strength. For most applications, however, the difference in power would not be noticeable.
Corrosion resistance
With its lower carbon content, 316L minimizes the chances of chromium carburizing. This property increases its resistance to corrosion in various forms, particularly after welding. It gives it an edge over 316.
Mechanical Properties for 316 vs 316L
Tensile strength
Engineers use tensile strength to measure a material’s ability to resist being pulled apart. 316L and 316 offer high tensile strengths, but 316 has a slight advantage due to its higher carbon content. It is, therefore, more suitable for applications that require higher power.
Yield Strength
The yield strength is the maximum stress a material can withstand without permanently deforming. The yield strength of both 316L and 316 is high, but the difference in carbon content can have a minimal impact. This difference is not significant for most applications.
Hardness
Hardness measures a material’s resistance to deformation under a load. The higher carbon content of 316 gives it a slight advantage in hardness compared to 316L. It’s important to note that the higher carbon content in 316 can make it more complicated than 316L.
Comparative Side-by-Side Comparison
Tensile strength
- 316：Has a typical tensile of 580-780 MPa.
- 316L: A slightly smaller range, 550-750 MPa.
316 has a higher carbon content, giving it an edge in tensile strength.
Yield Strength
- 316：The yield strength is usually between 290 and 310 MPa.
- 316L： A little less, usually between 280 MPa and 300 MPa.
Again, the higher carbon content of 316 could offer a slight edge.
Hardness
- 316：It has a Brinell Hardness of 150 to 160.
- 316L： Falling short of the mark with Brinell hardness between 140 and 150.
Corrosion resistance for 316 vs 316L
General Corrosion Resistant
316L and 316 offer both excellent corrosion resistance in general. They can withstand many different environments, including chemical and high-temperature conditions. The lower carbon content of 316L gives it an edge when resisting corrosion at welded joints.
Resistant to specific types of corrosion
Pitting
316 vs 316L resist pitting well, particularly when exposed to chlorides. Molybdenum is added to 316 and 316L to enhance their ability against this type of localized corrosion.
Crevice Corrosion
Both grades are resistant to crevice corrosion. The lower carbon content in 316L makes the steel slightly less vulnerable to decay, especially in welded areas.
Stress-Corrosion Cracking
The lower carbon content of 316L makes it more resistant to stress corrosion, especially in corrosive environments like chlorides or at higher temperatures.
Comparative Side-by-Side Comparison
General Corrosion Resistant
- 316：Excellent for various environments, including chemical and marine settings.
- 316L： A slightly superior steel, particularly in welding areas, due to the lower carbon content.
Resisting Pitting
- 316：High resistance, particularly when exposed to chlorides.
- 316L：Nearly identical resistance with a slight advantage in structures welded.
Resistant to Crevice Corrosion
- 316: Offers good resistance but can be vulnerable to some particular environments.
- 316L: It is slightly more resistant to corrosion, particularly when welds.
Resistant to Stress-Corrosion Cracking
- 361: Resistant in general but susceptible to certain conditions.
- 316L： Less susceptibility to corrosion due to the reduced carbon content. This makes it a better choice in environments prone to such corruption.
Which is better for heat resistance?
Heat Resistance of 316
316 Stainless Steel is heat resistant and can withstand temperatures up to 870degC. This makes 316 Stainless Steel ideal for environments that require heat resistance, such as the processing of chemicals and the aerospace industry.
Heat Resistance of 316L
316L Stainless Steel is also an excellent heat-resistant material, but it performs best in temperatures between 800-1580degF (425-860degC). The lower carbon content of 316L makes it less susceptible to sensitization. Stainless steels exposed to temperatures between 425-860 degrees Celsius experience this type of corrosion. This makes 316L particularly suitable for welded structures subjected to high temperatures.
316 vs 316L Stainless Steel – Which is Easier to Form and Weld?
Weldability of 316
Stainless Steel 316 is a good material for welding and performs well with different processes. Its higher carbon content may cause carbide precipitation within the heat-affected zones (HAZ). It could reduce corrosion resistance, particularly in areas welded after exposure to a corrosive environment.
Weldability of 316L
316L Stainless Steel is designed with a lower carbon content to make it less susceptible to carbide formation in the HAZ. Therefore, this material is a better option for welding, mainly when manufacturing requires it or when the welded component encounters corrosive materials.
Comparative Side-by-Side Comparison
Welding Techniques
- 316：Can weld using standard techniques but is more susceptible to carbide precipitation in the HAZ.
- 316L： Can be soldered using traditional methods but has a lower carbon content, which reduces carbide precipitation. It is slightly superior to 304L for welding.
After-welding corrosion resistance
- 316：The weld areas may have reduced corrosion resistance due to carbide precipitation.
- 316L： Its lower carbon content maintains its corrosion resistance, even when welded.
Easy of Use
- 316：It is easy to weld, but post-welding annealing may be required to increase corrosion resistance.
- 316L： Easy to solder for beginners and doesn’t usually require post-welding annealing.
316 vs 316L Stainless Steel – Which is More Cost Effective?
Market Price for 316
The price of 316 Stainless Steel fluctuates based on the market conditions. It is considered a premium quality due to its heat, corrosion resistance, and versatility in different industries. The price can vary depending on whether you want a sheet, bar, or tube.
Market Price for 316L
316L Stainless Steel also depends on market conditions but is priced similarly to 316. Even slight compositional differences rarely lead to significant price variations. Form and volume can also affect the final price you receive from suppliers.
Factors Influencing Price
Stainless steel 316L vs 316 can be affected by some factors.
- Market demand:High prices are often a result of high demand.
- Location of the supplier: Transport charges can affect the final price.
- Volume： Bulk Orders Usually Attract Discounts
- Form factor: Sheets, tubes, and bars each have pricing dynamics.
Comparative Side-by-Side Comparison
Unit Price
- 316:Prices may vary but are usually competitive when considering its heat resistance and corrosion resistance.
- 316L：Similar to 316 in price, but minor variations can occur depending on the market and supplier conditions.
Bulk Pricing
- 316:Vendors often offer discounts on bulk orders, making them more cost-effective.
- 316L：In general, discounts on large orders are available. This makes purchasing in bulk more cost-effective.
Supply Chain Considerations
- 316：Unique forms or finishes may incur additional costs.
- 316L: The total price is also affected by supply chain variables.
Lifecycle Value
- 316：Its durability and versatility make it an excellent long-term investment.
- 316L: Offers similar value over the long term but with additional benefits for specific applications, such as welded structures.
Which is Greener: 316 vs 316L Stainless Steel?
Sustainability in 316
316 Stainless Steel has a high recycling rate, adding to its sustainability. The long-lasting quality of 316 Stainless Steel reduces the frequency of replacements, reducing waste. The production of 316 is more energy-intensive due to the higher carbon content.
Sustainability in 316L
316L Stainless Steel is also highly recyclable and durable. Its lower carbon content leads to a slight reduction in energy consumption. It is more eco-friendly than 316 stainless steel.
Comparative Side-by-Side Comparison
Recyclability
- 316：Highly recyclable and can be melted and repurposed many times.
- 316L: Equally recycled and offering the same resource efficiency benefits.
Longevity
- 316:Durable, long-lasting, and minimizes waste over time.
- 316L： Displays high durability and contributes to a long lifecycle with reduced waste.
Production Energy
- 316：A higher carbon content results in a more energy-intensive production process.
- 316L: A lower carbon content leads to a slight reduction in energy consumption during manufacture.
Carbon Footprint
- 316：A higher energy consumption in production may contribute to an increased carbon footprint.
- 316L： It is a carbon-efficient option due to its reduced energy requirements.
Use-Case Scenarios: 316 vs 316L
When to use 316
High-Temperature Environments
The heat resistance of 316 makes it a good choice for boiler and furnace parts.
Corrosive Setting
The excellent corrosion resistance of this material makes it suitable for chemical and marine processing industries.
Versatility
316 is a versatile material used in various industries, from automotive to aerospace.
When to use 316L
Welding Projects
It is ideal for welding structures because it has a lower carbon content, which minimizes carbide precipitation.
Pharmaceutical Applications
The pharmaceutical industry chooses 316L because of its corrosion resistance.
High Purity Processes
A low carbon content is ideal for systems that require high purity.
conclusion
Your requirements will determine the choice between 316L and 316 stainless steel. Make an informed choice by evaluating your project. We’re always here to assist you at Shengen.
We appreciate your trust in Shengen to be your source for sheet metal fabrication components. We are committed to providing quality, reliability, and expertise.
More Resources:
Mechanical properties of 316L – Source: MatWeb
316 Stainless Steel, annealed sheet – Source: MatWeb
Hey, I'm Kevin Lee
For the past 10 years, I’ve been immersed in various forms of sheet metal fabrication, sharing cool insights here from my experiences across diverse workshops.
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Kevin Lee
I have over ten years of professional experience in sheet metal fabrication, specializing in laser cutting, bending, welding, and surface treatment techniques. As the Technical Director at Shengen, I am committed to solving complex manufacturing challenges and driving innovation and quality in each project.
