304 and 316 stainless steel: Key differences

 

Grades 304 and 316 are one of the most popular stainless steel grades. Both are versatile grades and are used in multiple industries. However, do you the difference between the two? This article explains the differences between grade 304 and 316 stainless steel grades.

Difference between 304 and 316 stainless steel

Here are the basic differences between 304 and 316 stainless steel.

	Grade 304 stainless steel	Grade 316 stainless steel
Corrosion	Corrosion and oxidation resistance	Resistance to chloride pitting
Tensile strength	The tensile strength of grade 304 is about 520-720 MPa	The tensile strength of grade 316 is about 530-680 MPa
Machinability	It is more machinable as compared to grade 316. The machinability rating of grade 316 is 70.	It is less machinable as compared to grade 304. The machinability rating of grade 316 is 60.
Cost	It is cheaper as compared to grade 316 stainless steel	It is more expensive as compared to grade 316 stainless steel
Durability	Since grade 304 is resistant to wear and tear, corrosion, fatigue, deformation, and heat, grade 304 is known to be a durable material.	Grade 316 is also known to be a durable material. Due to its better corrosion resistance, grade 316 has an edge over grade 304.
Melting point	Approx. 1400-1450°C.	Approx. 1375°C
Heat resistance	With a higher melting point, grade 304 is better heat resistant.	With a lower melting point, grade 316 can resist lesser heat compared to grade 304.

Here are more detailed differences between the two grades.

304 and 316 stainless steel: Chemical composition

The chemical composition of 304 and 316 stainless steel grades are completely different. One of the key differences is the presence of molybdenum. 304 grade stainless steel does not include any molybdenum content while 316 grade stainless steel has 2%-2.5% molybdenum. Moreover, the percentage of chromium content and nickel content also varies. Here are more details.

	Carbon	Chromium content	Nickel content	Molybdenum content
304 stainless steel	0.7%	17.5%-19.5%	8%-10%	–
316 stainless steel	0.7%	16%-18%	10%-13%	2%-2.5%

304 and 316 stainless steel: Corrosion resistance

Stainless steel is known for its corrosion resistance. However, the intensity of corrosion resistance varies depending on the grade. Here is how grade 304 and 326 are different in terms of corrosion resistance.

Grade 304 stainless steel	Grade 316 stainless steel
Grade 304 stainless steel does not contain molybdenum, making it comparatively less corrosion resistant.	Molybdenum makes grade 316 more corrosion resistant as compared to grade 304.
Grade 304 stainless steel is capable of withstanding corrosion from oxidizing acids. The feature makes it ideal to be used in kitchens, buildings, décor, etc.	Grade 316 stainless steel is capable of withstanding corrosion from chlorides and other processing chemicals. Therefore, grade 316 is ideal to be used in industrial applications involving chemicals and high saline environments.

Grades 304 vs. 316: pricing

There is a vast difference between the two grades. Here is how both the stainless steel grades are priced.

304 stainless steel pricing	316 stainless steel pricing
Approximately ₹150-₹250 per Kg.  depending on size and thickness.	Approximately ₹250-₹370 per Kg.  depending on size and thickness.

Note: Prices of stainless steel fluctuate often. Hence, it is best to check the prevailing price before making any decision.

Common features of grades 304 and 316

• Weldability: Weldability depends on the carbon content. Both, grades 304 and 316, contain about 0.7% carbon. Therefore, both materials are equally weldable. Both grades feature outstanding welding characteristics.
• Heat resistance: Both grades feature good heat resistance.
• Durability: Stainless steel is known to be a durable In the case of grades 304 and 316, both the grades are equally durable.

Applications: 304 vs 316 stainless steel

Here are some of the common applications of 304 stainless steel and 316 grade stainless steel. Because of differences in features and composition, these grades are used in various applications. Here is how 304 grade stainless steel and 316 stainless steel used.

Grade 304 stainless steel	Grade 316 stainless steel
Kitchen appliances like refrigerators and dishwashers Heat exchangers Food processing equipment Architectural paneling Storage tanks Fasteners Residential appliances Steel railings for balconies	Industrial applications such as chemicals and pharma equipment Marine equipment Medical and surgical equipment Commercial kitchens Pressure vessels Commercial appliances

 

So, what should you choose – grade 304 or grade 316?

When the cost of grade 316 is higher, should you choose 304 grade stainless steel? No. selection of grade depends on the application. Here is how you choose the right grade for your project.

• Firstly, determine your needs and expectations from the material. For example, in the case of marine applications 316 grade stainless steel will be suitable while for kitchen appliances 304 grade can be used.
• Consider the weather and environmental conditions. For example, grade 304 can corrode when exposed to chloride. Therefore, it is not the right choice for chemical equipment especially to be used with chloride.
• Check the budget of the project. For instance, when you do not need strong corrosion resistance, 304 grade can be an economical choice.
• Once you finalise the requirements and the budget, you can narrow it down to grade 304 or grade 316.

Conclusion: Tips to procure grade 304 and 316 stainless steel

• Determining the requirements helps in narrowing down the choices and eliminating materials that will not be suitable for the project.
• Once the expectations from the material are set, you can approach the vendors and invite the quotes.
• Economies of scale can help you buy stainless steel at a competitive price.
• Approach multiple vendors before finalising one. Understand pricing, delivery timelines and other terms and conditions.
• One of the easiest ways to easiest ways to procure 304 and 316 stainless steel is Tata nexarc. You can easily post your requirements, get quotes from multiple vendors, evaluate quotes and select the best one. Your order will be delivered to your doorstep.