Can stainless steel 304 and 316L be used together?
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Can stainless steel 304 and 316L be used together? Are there any risks to mixing them?
The corrosion resistance levels of 304 material and 316L material are different; 304 can be used, and 316L is an even better choice. However, if 304 can be used, then 316L is not necessary, as the price of 316L is much higher than that of 304. But if the design requires the use of 316L, then from the perspective of material corrosion resistance, 304 definitely cannot be used. Therefore, these two materials cannot be used interchangeably.
They cannot be used together, as the compositions of the two materials are different. In the presence of corrosion, 316L is the first to be corroded. Standards specify that stainless steel and carbon steel must not come into contact, as this can cause corrosion of the stainless steel.
Stainless steel grades 304 and 316L cannot be used interchangeably: As can be seen from 304 (0Cr18Ni9) and 316L (00Cr17Ni14Mo2), their carbon content as well as the metal elements added to them differ. It is possible to use a higher-grade material in place of a lower-grade one, but this is rather wasteful； It is not permissible to replace high-quality materials with lower-quality ones; taking factors such as corrosion into account, stainless steel grades 304 and 316L cannot be used together
What was said on the fourth floor is very good: choosing the right materials is a prerequisite to ensure safety and reliability in use, and then there’s the cost! So using a higher generation with a lower one is feasible but wasteful, while using a lower generation with a higher one poses problems in terms of safety and reliability.
I’m not sure what LZ means by \"mixed use\" – sometimes, to meet certain operational requirements, instrument valves are not made of 304 material; although the pipeline system uses 304, the instrument valves are still made of 316.
Intergranular corrosion will occur; they cannot be used together
Where 304 is used, 316 can be used just as well； Using this connection method can prevent the problem of intergranular corrosion. Now that we are using Q235 and 304 connected by flanges, the corrosion issue is not significant
It is possible to use the higher-grade material in place of the lower-grade one; their chemical compositions differ significantly. 304/C: 0.08, Si: 2.0, Mn: 1.5, Cr: 18–21, Ni: 8–11, Mo: 0.5. 316L/C: 0.03, Si: 1.5, Mn: 1.5, Cr: 17–21, Ni: 9–13, Mo: 2–3, S: 0.04, P: 0.04