410 Stainless Steel Screws In Aluminum
Because aluminum can expand a large distance the high hardness of 410 ss case harden screws may lead to screw to failure due to lack of ductility or stress corrosion cracking.
410 stainless steel screws in aluminum. Aluminum which has an anodic nature will quickly disintegrate when it comes into contact with salty water and will do the same when its surface area is less than that of stainless steel. Environments can affect the rate of corrosion and change the activity of the metals. Whether you choose a hex head screw or a pan head screw depends on the fastening tool and the desired appearance. When aluminum and stainless steel are used in an assembly together the electrons from the aluminum will begin to transfer into the stainless steel.
Without the need of a pilot hole. In this case 410 stainless steel will be more noble than the materials it is attaching. This can lead to an extended life of the stainless steel. However stainless steel is reactive with aluminum and when a stainless steel screw is in contact with an aluminum base metal the aluminum is likely to corrode.
The amount of area of the fastener is small compared to the material being fastened. This weakened aluminum causes it to deteriorate at a much faster rate. An example of the safe use of stainless steel fasteners with aluminum would be where stainless steel bolts are used to secure aluminum roadway parapet guards. Made from 410 stainless steel these screws are strong wear resistant and mildly chemical resistant.
Screws treated with a high quality coating consisting of zinc and aluminum. Deckfast metal screws are made of grade 410 stainless steel and feature extra deep star drive recesses undercut heads drill points and a color matched epoxy based polymer resin coating over zinc plate. This results in the aluminum weakening. By drilling their own holes and fastening in a single operation these square drive screws save time and effort.
In this case the surface area of the aluminum is so large relative to the surface area of the stainless steel bolts that there is a very low risk of major corrosion. It should be acceptable aas far a galvanic corrosion is concerned. Made of 410 stainless steel they re both stronger and more wear resistant than 18 8 stainless steel screws. Organic coating to the screw will improve the corrosion resistance.
As is the case with carbon steel screws a plated stainless steel screw is less likely to corrode aluminum. 410 stainless steel self drilling screws. Aluminum if left on. This is similar to using stainless steel rivets in al skin material on aircraft wings.
Use self drilling screw store fasten materials to aluminum or sheet metal up to 7 ga. Always ensure that the aluminum part of the material is larger than the stainless steel screws to avoid it being eaten away. Stainless steel hex head drilling screws for aluminum made from 18 8 stainless steel these screws have good chemical resistance.