Various countries are developing low-cost and high-performance new titanium alloys, striving to bring titanium alloys into the civilian industrial field with huge market potential. The new progress in research on titanium alloy materials at home and abroad is mainly reflected in the following aspects.
High temperature titanium alloy
The world's first successfully developed high-temperature titanium alloy is Ti-6Al-4V, with a service temperature of 300-350 ℃. Subsequently, alloys such as IMI550 and BT3-1 with temperatures up to 400 ℃ were developed, as well as alloys such as IMI679, IMI685, Ti-6246, and Ti-6242 with temperatures ranging from 450 to 500 ℃. New high temperature titanium alloys that have been successfully used in military and civil aircraft engines include IMI829 and IMI834 alloys from Britain; Ti-1100 alloy from the United States; BT18Y, BT36 alloys, etc. from Russia. Table 7 shows the maximum service temperatures for new high-temperature titanium alloys in some countries [26].
In recent years, the development direction of high-temperature titanium alloys abroad has been to use rapid solidification/powder metallurgy technology, fiber or particle reinforced composite materials to develop titanium alloys, which can increase the service temperature of titanium alloys to over 650 ℃ [1,27,29,31]. McDonnell Douglas in the United States has successfully developed a high-purity, high-density titanium alloy using rapid solidification/powder metallurgy technology. Its strength at 760 ℃ is equivalent to that of titanium alloys used at room temperature [26].
Titanium aluminum compound
Compared with general titanium alloys, titanium aluminum compounds are based on sodium Ti3Al（ α 2) And TiAl（ γ） The biggest advantages of intermetallic compounds are their good high-temperature performance (maximum operating temperatures of 816 and 982 ℃, respectively), strong oxidation resistance, good creep resistance, and light weight (density only half of nickel based high-temperature alloys), which make them the most competitive materials for future aviation engines and aircraft structural components [26].
Two Ti3Al based titanium alloys Ti-21Nb-14Al and Ti-24Al-14Nb - # v-0.5Mo have started mass production in the United States. Other developed Ti3Al based titanium alloys include Ti-24Al-11Nb, Ti25Al-17Nb-1Mo, and Ti-25Al-10Nb-3V-1Mo [29]. TiAl（ γ) The composition range of Ti based titanium alloys of concern is Ti - (46-52) Al - (1-10) M (at.%), where M is at least one element in v, Cr, Mn, Nb, Mn, Mo, and W. TiAl3 based titanium alloys have begun to attract attention, such as Ti-65Al-10Ni alloy [1].
High strength and toughness β type
β The earliest type of titanium alloy was B120VCA alloy (Ti-13v-11Cr-3Al) developed by Crucible Company in the mid-1950s in the United States. β T-shaped titanium alloy has good cold and hot workability, is easy to forge, can be rolled and welded, and can obtain high mechanical properties, good environmental resistance, strength and fracture toughness through solution aging treatment. New type of high strength and toughness β The most representative type of titanium alloy
