>What Is The Difference Between 300 And 400 Series Stainless Steel

What Is The Difference Between 300 And 400 Series Stainless Steel

the 300 series stainless steels are austenitic stainless steels with non-magnetic properties. They have have 17% to 19% chromium, 8-10% nickel, manganese, carbon, sulfur, phosphorus and silicon in the composition. These are corrosion resistant stainless steels and are one of the most widely used types of steels. The grades vary such as 302, 304 and 316. The 304 is the most used of all stainless steels and the 316 is the second most used of all stainless steels in various applications. The 400 series is ferritic stainless steels with 11% chromium, manganese, sulfur, phosphorus and other elements in smaller quantities. These materials contains little to no nickel in the composition. They have poor corrosion resistance compared to the 300 series but have high abrasion resistance and wear and tear resistance. The grades vary such as 403, 405, 409, 410 and so on.

300 And 400 Series Stainless Steel Price Difference

Since the nickel content is low, the 400 series is cheaper than the 300 series of stainless steels. The 300 series is used in applications that require corrosion resistance where the 400 series is applied in applications that require high wear and tear resistance. However, the 300 series is most used because most of the applications consider corrosion resistance over the wear and tear capacities.


300 And 400 Series Corrosion Resistance Levels

The chromium content in the 400 series provides some level of corrosion resistance but it is poor against steam, flowing water, chlorides, oxidizing agents and reducing agents. However, the 300 series provides better strength and corrosion resistance against most of these corrosive agents. Some particular grades such as the 316 grade have higher corrosion resistance against specific agents such as the chloride ion. So the 300 series of products are used in marine, oil and gas, petroleum, petrochemical, oil and gas and in other applications where the products are prone to corrosion risk. The 400 series is used applications such as transportation, platforms, handrails, automobile parts and other applications where the wear and tear is high but the corrosion resistance is not the primary concern.

 

300 Vs 400 Series Tensile And Yield Strength


The yield strength of the 400 series grades is about 30ksi where that of the 300 series is about 40ksi. The tensile strength is also high for the 300 series with 100ksi where that of the 400 series is about 70ksi. This difference is caused by the lack of nickel content in the 400 series of steels. The combination of chromium and nickel is also the main reason for the difference in the corrosion resistance as well.

300 And 400 Series Stainless Steel Weldability


The 300 series is good for welding compared to the 400 series. The 400 series can cause deformations and cracking during welding. Both these materials can be welded with most traditional methods, but the 300 series could be welded without causing any damages to the material. The 400 series can crack and is often welded with 304 grade of sheet metal from the 300 series to make sure that there is a more fluid weld puddle and the bridging of gaps can be better performed.

 

Features & Specification of 300 Series and 400 Series
VALUES COMPARISON CHART DUPLEX STEEL SS 304L AND 316L SS 410 AND 416
CORROSION RESISTANCE Excellent Good Moderate
MACHINABILITY Excellent Poor/Gummy – will not hold bright finish Good
WELDABILITY OF STEEL Excellent Good Moderate¹
SOUR SERVICE (SS) ENVIRONMENTS Excellent Poor Acceptable
STRENGTH OF STEEL Excellent Poor / Not hardenable by heat treatment Good
ANTI-GALLING Good Poor / Parts can seize and gall Moderate / Parts can seize
WEAR RESISTANCE Excellent Moderate Good/Further hardening diminishes
MAGNETIC Yes No Yes
SHOCK RESISTANCE Excellent Excellent Good
RETAINED STRESS Less retained stress Poor / High degree of memory Moderate / High degree of memory
LONG LENGTHS AVAILABLE Yes No Yes
FINISH OPTIONS TGP Bearing-Fit, RTOS Centerless TGP, Cold Drawn Hot Roll, TGP
YIELD STRESS (TYP) 65,000 PSI minimum 304L = 25,000 PSI
316L = 30,000 PSI
410 = 90,000 PSI
416 = 110,000 PSI
SERVICE TEMPERATURE RANGE 750°F 304L = 1100°F
316L = 1400°F
410 = 1100°F
416 = 1100°F
TENSILE STRESS (TYP) 94,000 PSI minimum 304L = 70,000 PSI
316L = 75,000 PSI
410 = 120,000 PSI
416 = 124,000 PSI
THERMAL HARDENABILITY No No² Yes

 

300 Series Stainless Steel grades
302 bit higher strength and corrosion resistance is similar to 304
301 Known for Better weldability and fatigue strength compared to SS 304
321 Addition of titanium alloy
304 Most popular grade, also known as 18/8 stainless steel, A2, ISO 3506
316 ANother most popular grade after 304, also known as marine grade, A4, ISO 3506
303 Also known as "A1", ISO 3506
309 temperature resistance is good compared to grade 304

 

400 Series Stainless Steel grades
409 Its one of the cheap grade mainly used in automobile
408 Contains 8% Nickel. 11% Chromium
416 Contains additional sulfur
430 Have excellent formability
440 Contains additional carbon, comes different grades 440A, 440B, 440C and 440F
410 less corrosion resistant and Wear resistant grade
420 Also known as surgical steel, have good polishability