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合15～50％Cr的镍铬合金在强氧化性介质中的耐蚀性能,随Cr量提高而增强,是含Cr量的函数。在含Cr量与耐蚀性曲线上于35％cr和50％Cr处出现两个拐点。当含Cr量大于50％或加入Ti、Ti和Fe以及Ti、Fe、Cu时,则使合金耐蚀性受到损害。Cr50Ni50对高温含硫和钒的燃料灰具有耐蚀性。Cr35Ni65在沸腾65％、98％硝酸中耐蚀性最好。热塑性实验查明Cr30Nj70合金在1000～1200℃有一低塑性区存在,热变形很困难,锻坯发生开裂而报废。采用在合金中加入微量Al的方法,可使这一低塑性区缩小甚至消除,合金锻压件收得率由25％提高到70％。生产实践表明,这种用微量Al改善合金热塑性方法亦适用于含35～50％Cr的镍基耐蚀合金。
Corrosion resistance of 15% to 50% Cr Ni-Cr alloy in strongly oxidizing media increases with increasing Cr content and is a function of Cr content. Two inflection points appear at 35% cr and 50% Cr on the Cr content and corrosion resistance curves. When the amount of Cr is more than 50% or adding Ti, Ti and Fe and Ti, Fe and Cu, the corrosion resistance of the alloy is impaired. Cr50Ni50 Corrosion resistance to high temperature sulfur-and vanadium-containing fuel ash. Cr35Ni65 65% boiling, 98% nitric acid corrosion resistance best. Thermoplastic test shows that Cr30Nj70 alloy has a low plasticity zone at 1000 ~ 1200 ℃, it is very difficult to heat deformation, cracking of the forging blank and scrapped. Adopting the method of adding trace amount of Al into the alloy, this low plasticity area can be reduced or even eliminated, and the yield of alloy forging increases from 25% to 70%. Production practice shows that this method of improving the alloy with a trace amount of Al is also suitable for nickel-based corrosion resistant alloys containing 35-50% Cr.