Alloy20 Material introduction

Alloy20（UNS N08020/NS143）It is an iron nickel base corrosion resistant alloy developed on the basis of high nickel austenitic stainless steel - 0Cr20Ni28Mo3Cu3Nb (Carpenter 20Cb) in 1963. It is called Carpenter 20Cb-3 or 20Cb-3 alloy for short internationally. Alloy20 is a high nickel deformable austenitic stainless steel with good corrosion resistance to H2SO4, HNO3 and their mixed acids developed in 1948. However, when dissolving the stainless steel cladding of nuclear fuel, it was found that the steel produced stress corrosion cracking in 3mol/L H2SO4. In order to solve this problem, it is found through research that under the condition that the composition of other alloys is basically the same as Carpenter 20Cb, the nickel content in steel is only increased from 27% - 29% to 33% - 38%, which not only improves the stress corrosion cracking resistance of steel, but also greatly improves the corrosion resistance and machinability of steel in reducing acid, leading to the birth of 20Cb-3 alloy. Because of its good corrosion resistance, the alloy has been widely used in chemical processing and other industries.

Alloy20 chemical composition

Alloy20 Physical and mechanical properties

Alloy20 Heat treatment system

The suitable final heat treatment for this alloy is 940 ℃ stabilization treatment. The intermediate annealing temperature should be higher than 1050 ℃ solution softening annealing temperature.