Stainless Steel Square Bar Drawn and Peeled EN 1.4404
The austenitic steel with designation 1.4404 contains molybdenum in addition to chromium and nickel. The difference against 1.4301/1.4307 apart from the presence of molybdenum is that the nickel content is greater. This type of stainless steel is often referred to as acid resistant which is to some degree a misnomer since the material resists attack only by weak acids. 1.4404 has low carbon content which means that it can be welded without risking impairment of corrosion resistance in the vicinity of the weld. In terms of strength, 1.4404 is more or less equivalent to the lower alloyed grades 1.4301/1.4307.
Square bars of stainless steel are manufactured by hot rolling. In square format, the grade 1.4404 is standardised in EN 10088-3. Tibnor’s programme of hot-finished stainless square bars encompasses edge lengths in the range 10-50 mm (the finished execution of dimension 10 mm is cold-drawn).
The presence of molybdenum along with chromium renders 1.4404 resistant to corrosion in weak acids and water containing chlorides so long as the chloride concentration is not too high; an example of an environment where the steel works well is salt-laden coastal atmosphere.
The formability of hot-finished square bars in grade 1.4404 is in most cold-forming operations excellent and often better than hot-rolled carbon steel. The material is also characterised by very good weldability and seldom gives rise to any problems in fabrication of welded structures. Machining, on the other hand, can pose difficulties but is facilitated via use of bespoke tooling.
Hot-finished squares in grade 1.4404 have surface finish 1D as defined in EN 10088-3 (annealed and with surface oxide removed by pickling). The tolerance for edge length is a plus/minus tolerance as defined in EN 10059. Straightness expressed as height of arc is at most 0.004 times the bar length.