Can NAS254N be replaced with NAS254NM?

In terms of composition, performance, and corrosion resistance, these two materials are quite similar. NAS 254NM (equivalent to UNS N08367) is a highly corrosion-resistant stainless steel containing high levels of chromium and molybdenum. It maintains excellent corrosion resistance even in harsh environments such as high temperatures, seawater, or flue gas desulfurization equipment. In certain environments, it can rival Hastelloy and titanium plates; it is a cost-effective stainless steel with high corrosion resistance. Corrosion resistance: Due to the high concentration of chromium, molybdenum, and nitrogen in NAS 254NM, it exhibits excellent resistance to pitting corrosion and intergranular corrosion even in chloride-containing environments. NAS 254N is a highly corrosion-resistant stainless steel containing high levels of nickel, chromium, and molybdenum. It maintains extremely excellent corrosion resistance even in harsh environments such as seawater at high temperatures.

What type of corrosion is high-nickel mainly used to prevent?

NAS 254N is a highly corrosion-resistant stainless steel containing high levels of nickel, chromium, and molybdenum. Can NAS 254NM be used as a substitute?

Original poster, those who work with materials really avoid talking about substitutes. You need to provide details such as the operating conditions of your medium, so that others can make an assessment. It seems that these two materials are not readily available in China; if you need them, I can help you check in Japan!