Looking for the right stainless steel for your project? With so many options available, it can be overwhelming to choose the best one.
That’s why we’ve put together this comprehensive guide to help you understand the differences between S30408 and 304 stainless steel.
From their chemical compositions to their mechanical properties, we’ll break down everything you need to know to make an informed decision.
Plus, we’ll delve into the safety considerations for using these materials in food applications.
Whether you’re working on a large-scale industrial project or a small DIY endeavor, this article will provide you with the insights you need to choose the perfect stainless steel for your needs.
So, read on to discover the key differences between S30408 and 304 stainless steel and find the right material for your project today!
There are three key differences between S30408 and 304 stainless steel:
- The UNS numerical code for S30408 is 06Cr19Ni10, while the UNS numerical code for 304 is S30400;
- The chemical composition of S30408 differs from 304 in terms of carbon (C), phosphorus (P), sulfur (S), and chromium (Cr) content;
- The mechanical properties of S30408 and 304 are slightly different, specifically in terms of yield strength.
So which one is better – S30408 or 304? And what are the differences between them? It’s important to consider the safety of using these materials in food applications. I will delve into these three points in greater detail.
1. Is S30408 the same as 304?
Is Stainless Steel S30408 the same as 304?
S30408 is a designation for one of the austenitic stainless steels according to the UNS numbering system.
S30408 stainless steel is equivalent to 06Cr19Ni10, which is a common type of stainless steel material.
The corresponding UNS number for 304 is S30400, so S30408 and 304 are not identical.
2. Origin of S30408
The UNS numbering system is a system that assigns numerical codes to 18 different series of metals and alloys. The UNS number consists of a single letter prefix followed by five Arabic numerals. The prefix letter usually represents the metallicity, such as “S” for stainless steel. The number that follows, such as 304, is the grade code that indicates the Cr Ni content of the austenitic 300 series stainless steel.
Different Cr Ni content percentages result in different grade codes, such as 301, 316, and 321. So, S30408 is the UNS numerical code for stainless steel with a specific Cr Ni content percentage.
3. Chemical composition difference between S30408 and 304
| Standard name | UNS code | Grade | C | Mn | P | S | Si | Cr | Ni | N | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| American Standard | ASTM A240M-15a | S30400 | 304 | 0.07 | 2.00 | 0.045 | 0.03 | 0.751 | 7.5-19.58 | 8.0-10.5 | .. |
| China standard | GB/T24511-2017 | S30408 | 06Cr19Ni10 | 0.08 | 2.00 | 0.035 | 0.015 | 0.751 | 8.0-20.08 | 8.0-10.5 | 0.1 |
| Japanese standard | JISG4305:2012 | SUS304 | 0.08 | 2.00 | 0.045 | 0.03 | 1.00 | 8.0-20.08 | 8.0-10.5 | .. | |
| European Standard | EN10028-7:2016 | 1.4301 | 0.07 | 2.00 | 0.045 | 0.015 | 1.00 | 7.5-19.58 | 8.0-10.5 | 0.1 | |
Note: The proportion is expressed as a percentage, i.e. “%”. Unless otherwise stated, the components listed in the table are the maximum values.
The chemical composition of S30408 and 304 stainless steel is slightly different. For instance, 304 requires a lower carbon content, whereas S30408 requires lower levels of phosphorus and sulfur, and a higher content of chromium.
The chemical composition standards for S30408 and 304 materials can be found in the S30408 and 304 chemical composition comparison table above.
Both S30408 and 304 stainless steel are considered food-grade materials and meet the national standards for food-grade stainless steel.
In terms of safety, both S30408 and 304 stainless steel can be used for items such as kettles, children’s cups, food containers, and cookware.
4. Differences in mechanical properties between S30408 and 304
Mechanical Properties of Austenitic Steel after Solution Treatment at Room Temperature
| Number code | Grade | Specified plastic extension strength RPo. 2/MPa | Specified plastic extension strength RP1.0/MPa | Tensile strength Rm/MPa | Elongation after fracture A% | Hardness value | ||
|---|---|---|---|---|---|---|---|---|
| HBW | HRB | HV | ||||||
| Not less than | Not greater than | |||||||
| S30408 | 06Cr19Ni10 | 220 | 250 | 520 | 40 | 201 | 92 | 210 |
Mechanical Test Requirements
| Yield Strength | Tensile Strength | Elongation in 2 in or 50mm. min | Hardness.max | |
|---|---|---|---|---|
| Mpa | Mpa | % | BrinellHBW | Rockwell |
| 205 | 515 | 40 | 201 | 92 HRBW |
In terms of mechanical properties, there is little difference between stainless steel S30408 and 304. The yield strength, tensile strength, elongation, and hardness of the two can be compared and analyzed by referring to the table above.
Mechanical properties limit the use of materials, and the strength and hardness of 304 cold-rolled stainless steel coils are higher than those of S30408 hot-rolled stainless steel coils, though the latter has better processing performance and plasticity.
It’s important to note that S30408 stainless steel coils are mostly hot rolled, while the plasticity of 304 cold-rolled stainless steel is reduced, affecting its stamping performance.
This article aims to provide an understanding of the differences between stainless steel S30408 and 304, and help in making a decision on which material is better suited.
