Aero-engine fastener material

Because of the high temperature environment of aero-engine, fasteners are required to have the characteristics of high temperature resistance and high fatigue resistance.When selecting materials for engine fasteners, often choose with good high temperature performance of materials.Generally speaking, in the high temperature parts of the engine, the fastener materials are mostly made of high temperature alloys, such as GH2132, GH4738 and GH4169;At low temperature parts, the fastener materials are mainly using stainless steel and alloy steel, such as 1Cr11Ni2W2MoV, 40CrNiMo, etc;If there is a need to reduce weight, titanium alloy fasteners can be selected specifically.    

At present, a large number of superalloy fasteners based on iron and nickel based superalloy are used for foreign engines, including A286, Wasploy, Inconel718, etc. The highest service temperature of corresponding fasteners can reach 425℃, 650℃ and 730℃. For bolt products, more than 90% of them are Inconel718;  For nuts and self-locking nuts matching with bolts,  Wasploy and A286 are the main materials.Compared with foreign countries, domestic aircraft engines still use a large number of stainless steel and alloy steel fasteners such as 1Cr11Ni2W2MoV and 40CrNiMo. The high temperature strength and high temperature durability of these materials are far behind that of high temperature alloy materials.  This greatly restricts the technical development of aero-engine fasteners in China. With the continuous increase of national investment in aero-engine, the localization of high temperature alloy rod and wire for fasteners such as GH2132 and GH4169 has been carried out in recent year.