Titanium Compared with other metals, it has the following advantages

Titanium Compared with other metals, it has the following advantages:
① specific strength (tensile strength / density) High (pictured), a tensile strength of up to 100 ~ 140kgf / mm2, while only 60% of the density of steel.
② temperature strength, operating temperature of several hundred degrees higher than aluminum, at moderate temperatures can still maintain the desired strength, long-term work at a temperature of 450 ~ 500 ℃.
③ good corrosion resistance, titanium surfaces in the atmosphere immediately form a uniform layer of dense oxide film, there is resistance to a variety of media erosion. Typically Titanium has good corrosion resistance in oxidizing and neutral medium, more excellent corrosion resistance in seawater, wet chlorine and chloride solution. But in reducing media, such as hydrochloric acid solution, and corrosion resistance of titanium is poor.
④ low temperature performance, low interstitial elements of titanium, such as TA7, at -253 ℃ can maintain a certain degree of plasticity.
⑤ low elastic modulus, low thermal conductivity, no ferromagnetism.
6. High hardness.
7. stamping poor, thermoplastic good.
Titanium heat treatment can be obtained by adjusting the heat treatment process and the organization of different phases. It is generally believed that the fine equiaxed has good plasticity, thermal stability and fatigue strength; needle tissue has a high rupture strength, creep strength and fracture toughness; equiaxed and needle mixed structure has good overall performance.
Commonly used methods are annealing heat treatment, solution and aging treatment. Annealing is to eliminate stress, improve plasticity and organizational stability, in order to obtain a better overall performance. Typically α alloy and (α + β) alloy annealing temperature selected in the (α + β) - → β phase transition point below 120 ~ 200 ℃; solution and aging treatment is rapid cooling from the high temperature zone, in order to obtain martensite α ' phase and the metastable β phase, and then incubated in the temperature region of these metastable phase decomposition to obtain compound α phase or the dispersed second phase particles, achieve the purpose of strengthening the alloy. Typically (α + β) quenching the alloy in (α + β) - → β phase transition points below 40 ~ 100 ℃ carried metastable β quenched alloy in the (α + β) - → β phase transition point above 40 ~ 80 ℃ get on. Aging treatment temperature is generally 450 ~ 550 ℃. In addition, in order to meet the special requirements of the workpiece, the industry also uses double annealing, isothermal annealing, β heat treatment, deformation and heat treatment of metal heat treatment process.