Whether nails, screws, or bolts metal fasteners hold together the modern world. For most applications, fasteners made out of common metals such as stainless steel prove more than adequate. Yet other projects - specifically those that involve extreme temperatures - require special types of fasteners that most people are not familiar with.
These fasteners are composed of metals that display the kinds of resistance necessary to withstand extreme environments. If you would like to learn more about the sorts of fasteners used for high-temperature applications, read on. This article will introduce you to the three categories of high-heat fasteners.
1. Nickel Alloy Fasteners
The term alloy refers to any substance composed of two or more metals. Believe it or not, most commonly used metals are themselves alloys. For instance, stainless steel is an alloy composed of iron, chromium, nickel, and various other elements. Different alloys possess different qualities with regards to things like melting point and corrosion resistance.
When it comes to fastening components in high-temperature situations, alloys that contain larger amounts of nickel often come into play. Such alloys tend to display a greater resistance to oxidation, which can occur much more easily at high temperatures. Oxidation refers to a chemical reaction that causes ironcontaining metals to develop rust and other forms of corrosion.
Corrosion isn't the only problem facing metals in high-temperature scenarios. The higher the temperature grows, the more a metal's strength will decrease. This makes it much more susceptible to breaking under the strain of continued use. Nickel alloys possess high-temperature strength ratings much greater than that of simple stainless steel.
2. Refractory Metal Fasteners
As strong as they are, even nickel alloys can't resist the intense heat generated inside of certain types of furnaces. When it comes to resisting temperatures above 2,000 degrees Fahrenheit, so-called refractory metals must be used. These metals possess melting points thousands of degrees greater than common metals like steel.
Refractory metals include such substances as molybdenum, niobium, rhenium tantalum, and tungsten. If you aren't familiar with those names, don't worry. The incredible properties of such metals come at a high cost, one that makes these metals quite rare outside of a few highly specific uses. A single refractory metal bolt might easily contain $100 worth of material.
In addition, to offering incredibly high melting points, these metals also excel in terms of hardness and density. Better yet, they display a high level of stability when it comes to so-called creep deformation. This term refers to the susceptibility of a metal to undergo changes in shape when placed under stress.
3. Ceramic Fasteners
Believe it or not, even refractory metals don't hold the distinction of having the greatest resistance to heat. That honor falls to the category of so-called ceramic fasteners. These may be composed of one of two substances: alumina and zirconia. Alumina fasteners offer temperature resistances of up to 3000 degrees Fahrenheit, while Zirconia fasteners go even higher, with temperature ratings of as much as 4350 degrees Fahrenheit.
This makes ceramic fasteners the best fasteners when it comes to high-temperature applications. Better yet, ceramic fasteners also possess phenomenal resistance to corrosion and other forms of chemical degradation. Additionally, ceramic fasteners have a non-conductive nature that makes them especially wellsuited for high-voltage needs.
The world of fasteners tends to be much broader and deeper than many people realize. New types of fasteners are continually being developed in order to keep pace with rapid technological changes. To learn more about what type of fastener would be best suited for your needs, please don't hesitate to contact our industry experts at Ascension Fasteners.