Type of microstructure within the material area of stainless steel, in which about half of the basic structure types ferrite and half austenite result in the so-called duplex steel as a mixed structure. The term lean means a lower proportion of costly alloying elements. The reference material for the designation with Lean is the standard or common duplex steel 1.4462, which has been known for many years. The new grades designated as stainless Lean Duplex steels are 1.4062, 1.4162, 1.4362, 1.4482 and 1.4662, i.e. all materials which are lower alloyed than 1.4462.
In comparison to pure austenitic grades (e.g. 1.4301, 1.4404/1.4571), technical highlights are the significantly higher strength, the higher modulus of elasticity that can be applied and, in normal atmospheric ranges (up to 50°C), a higher corrosion resistance, especially where there is a risk of stress corrosion cracking.
see also: 1.4062 Lean Duplex, 1.4162 Lean Duplex, 1.4362 Lean Duplex, 1.4482 Lean Duplex