Lilac Garden Forum
switched zhangsimon There are a lot of definition is: a titanium-based alloys by adding other elements of the alloy known as titanium. Titanium has a low density, high specific strength, good corrosion resistance, and good process performance, is an ideal space engineering structural materials. < br> scope of the study: the structure of titanium alloy and titanium alloy can be divided into heat-resistant titanium or a titanium alloy, b-type titanium alloy, and a + b type titanium alloy. study also include forming technology of titanium alloys, powder metallurgy technology , rapid solidification technology, titanium and other military and civilian.
(a) the early development of
50 to 70 in the early
demand drivers: In order to meet the needs of the aviation industry on the material, titanium attention and to develop technology is based primarily on metallurgy and technology.
main features: the characteristics of this phase is gradually shifting the material exploration and research applications. main materials are Ti-6Al-4V, Ti-5Al-2.5Sn etc. , mainly used in aviation engine, aerospace pressure vessels, shell and other engines.
typical results and products: typical materials: Ti-6Al-4V, Ti-5Al-2.5Sn
70's to 90's
demand drivers: titanium expansion of application fields, so that the rapid development of titanium industry, new technology and new technology to promote the development of titanium alloy forming process.
main features: the characteristics of this phase 1) application of titanium content in the aerospace industry increasing in other sectors such as marine engineering, chemical engineering, electric power, metallurgy, medical, and other applications are becoming increasingly more and become the third metal. (2) continue to come out of new titanium alloy, such as high-strength titanium alloys, heat-resistant titanium alloy. (3) using new technology such as super plastic forming, rapid solidification and isothermal forging. (4) To expand the application of the emphasis on cost reduction.
typical results and products: typical materials: Ti-1100, Ti-1023 , IMI834, Timetal62S, SP-700 and other
(b) the existing level and development trend of the aerospace industry
Titanium is used widely as a metal material, the structure can be divided by end-use and high temperature titanium alloy alloys (temperature> 400 ℃).
structural titanium alloy to Ti-6Al-4V as the representative of the alloy has been widely used in aircraft, missiles, and by the time the main bearing structure turn structure. In order to meet the requirements of higher strength and toughness (such as strength increased to 1275 ~ 1373MPa, compared to 29 ~ 33 strength, elastic modulus increased to 196GPa), developed in recent years, many new titanium alloy, such as the United States, Ti-15V-3Cr -3Sn-3Al; Ti-3Al-8V-6Cr-4Mo-4Zr (bC), Ti-6Al-2Sn-2Zr-2Cr-2Mo-0.23Si, Ti-4.5Al-1.5Cr; UK Ti-4Al-4Mo -2Sn-0.5Si (IMI500), Japan, SPF00, CR800, SP700 and the former Soviet Union, BT22 and so on. which Ti-15-333 can replace castings and bC precipitation hardening stainless steel and nickel-based alloy, Ti-6-22-22 in U.S. Advanced Tactical Fighter (ATF) of the prototype F-22A used in the accounts for 22% (weight). Japan's SP700 (Ti-4.5Al-3V-2Mo-2Fe), not only high strength, but also in the 755 ℃ of superplasticity, up to 2000% elongation, formability is good, low cost, can replace the Ti-6Al-4V, has been used in aerospace components.
made some progress in recent years, high temperature titanium alloy, in the field, the United States and Britain occupy advantage. But the two methods used in the development and focus are different. Britain is a phase used to improve the creep strength of solid solution strengthening of the necessary means to co-exist without b-phase approach, focusing on the past a type of alloy, developed to improve the creep strength is mainly Ti-4Al-2Sn-4Mo-0.5Si (temperature 400 ℃), Ti-11Sn-2.25Al-5Zr-1Mo-0.2Si (IMI679, temperature 450 ℃), Ti -6Al-5Zr-0.5Mo-0.25Si (IMI685) to improve the fatigue strength of alloy and consisting mainly of Ti-5.5Al-3.5Sn-3Zr-1Nb-0.3Mo-0.3Si (IMI829) and Ti-5.5Al-4.5Sn -4Zr-0.4Mo-0.8Nb-0.4Si (IMI834).
by the United States to improve the fatigue strength at the expense of creep strength of the approach, focusing on higher levels of molybdenum alloys such as Ti-6Al-2Sn-4Zr -2Mo (6242, temperature 470 ℃), 6242S (temperature 500 ℃) alloy. Later, research and development of the Ti-6Al-2.7Sn-4Zr-0.4Mo-0.45Si alloy (Ti-1100), the use of temperature increased to 600 ℃.
Recently, the U.S. has developed Timetal21S (Ti-15Mo-2.7Nb-3Al-0.2Si) (also known as b21S), temperature 704 ℃, can be used to manufacture high temperature and pressure catheter tube, is preferably National space plane (NASP) metal matrix composite body of matrix material. At present, these new high-temperature titanium alloys are not yet entered the practical stage.
*** current high strength titanium alloy forming technology has developed rapidly, The trend is forming, isothermal forging pressure and vacuum forming method.
the United States in the development and application of titanium alloy, has been in the lead, according to statistics in the U.S. aviation industry, titanium ratio of 70% of consumption, the United States titanium forming, the main use of superplastic isothermal forging conditions and under the sheet metal forming. To reduce costs, increase applications, the U.S. launched a new brand of alloys, such as Timetal62S (Ti-6Al-2Fe-0.1Si), with iron on behalf of the the cost of vanadium than Ti-6Al-V, and the performance equivalent.
titanium industry has been the former Soviet Union more than 35 years of history, and its smooth development process, there are no major ups and downs. production of a large number of and Ti -6Al-4V and Ti-5Al-2.5Sn similar series of high-Wen Gaoqiang alloys, and alloys, and studies of special corrosion resistant alloy, such as 4200,4210,4207 and so on, in the aerospace industry, widely used in superplastic conditions of the former Soviet Union titanium alloy under the pressure forming process.
British thermal research and application of titanium with the United States each edge, but the focus of nearly a type of alloy, that is, vigorously develop the focus to improve creep strength of the alloy, such as Ti-4Al-2Sn-4Mo-0.5Si, Ti-11Sn-2.25Al-5Zr-1Mo-0.2Si (IMI879), Ti-6Al-5Zr-0.5Mo-0.25Si (IMI685), etc., which have been in Europe IMI685 widely available.
recent years, Japanese research in titanium has also made great progress, such as to reduce the cost of developing the SP-700 (Ti-4.5Al-3V-2Mo-2Fe) alloy, the alloy forming better than Ti-6Al-4V. Japanese low strain rate superplastic vacuum forming process.
in the dental field, are using the international label, or titanium ---- G2 type (made of the A2 type) for many.
Ti-6Al-4V, Ti-5Al-2.5Sn materials such as titanium alloy because of good physical properties and processing performance is done as a titanium dental research for some time, but because of Al / V and other elements biology is not the ideal elements and fade out the field of dentistry.
domestic and foreign scholars have studied Ti-Zr alloys such as Ti in the dental field in order to enhance the use value, but a few years may be due on the one hand I think the pure more in-depth understanding of titanium, partly because of the titanium alloy for dental research with less cost and large, so the application of titanium alloys for dental fact has not yet appeared.
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