بررسي ابر آلياژهاي ديرگداز نسل جديد پايه ايريديم (طراحي ، خواص مكانيكي و ساختار)

A study of the New Cienration of Ir-Based Refractory Superalloys (Design , struture & Properties )

The requirement of airospase industries on higher efficiency of jet engine in recent years make the necessity of using materials capable of application at high temperatures very obvious. To make this end meet two structure phase alloys based on pt element group, which has high melting points and fcc,Ll z struture were considered to be suitable , so that Ir base alloys with fcc structure and a melting point of about 2447 °C have been recommended for use in high temperature application. Among these alloys two phase 1r-Nb and Ir-Zr alloy due to their high strength and high resistance to creep at high temperature and it--Al alloy due to it is high resistance to oxidation and suitable toughness are the most used alloys. However, high densites and in some cases lower toughness in addition to reduction of strength at temperatures higher than 1200 °C forced the researchers to use more alloying elements for improving their properties particularly at higher temperatures. so, third and later fourth alloying element were added to two alloy system in order to get better properties. This research summarized these activities and Discussed The properties of 1r-base alloys.