Alloy 405 / UNS N04405 / W.Nr. 2.4363
Alloy 405 is a nickel-copper alloy that is an enhanced machining version of alloy 400. A controlled amount of sulfur is added to improve machinability. Corrosion resistance characteristics and physical properties are similar to alloy 400, but the mechanical property ranges diﬀer slightly. Alloy 405 can be slightly magnetic at room temperature, like alloy 400.
Industries and Applications
Alloy 405 is used in the same industries as alloy 400. Both alloys are heavily used in the chemical processing, pollution control and marine industries. This enhanced machining version of alloy 400 is intended to be machined using automated equipment. Applications include screw-machine products, water meter and valve seat components, ﬁttings and fasteners.
Resistance to Corrosion
Alloy 405 exhibits similar corrosion resistance to alloy 400. These alloys are resistant to corrosion in many reducing media. Like alloy 400, alloy 405 is one of the few alloys that can be used in contact with ﬂuorine, hydroﬂuoric acid, hydrogen ﬂuoride or their derivatives. Exceptional corrosion resistance has been proven in hydroﬂuoric acid in all concentrations up to the boiling point. Alloy 405 is also resistant to many forms of sulfuric and hydrochloric acids under reducing conditions. Corrosion resistance behavior in seawater is outstanding.
Fabrication and Heat Treatment
Alloy 405 was speciﬁcally designed for enhanced machinability and is recommended for use with automatic screw machines. The nickel copper sulﬁdes that form due to the increased sulfur content aid in machining and act as chip breakers. These inclusions can have an eﬀect on the surface ﬁnish, resulting in a slightly rougher ﬁnish than standard alloy 400. Alloy 405 can be fabricated and heat-treated using the same procedures as alloy 400. However, the alloy is not recommended for forging.