The tensile strength of pure titanium is 265-353MPa, the general titanium alloy is 686-1176MPa, and the current maximum is 1764MPa. Titanium alloys have the same strength as many plates of steel but are much better than strength titanium alloys. The specific strength here refers to the strength of the material divided by its apparent density, which is also called the strength-to-weight ratio. The international unit of specific strength is (N/m2)/(kg/m3) or N·m/kg. The ratio of the tensile strength of the material to the apparent density of the material is called the specific strength. The ratio of the strength (stretch) to the density of the material at the breaking point.
The compressive strength of titanium and titanium alloys is not lower than its tensile strength. The compressive yield strength and tensile yield strength of industrial pure titanium are roughly equal, while the compressive strength of Ti-6Al-4V and Ti-5Al-2.5Sn alloys is slightly higher than the tensile strength. The shear strength is generally 60%-70% of the tensile strength. The bearing yield strength of titanium and titanium alloy sheets is 1.2-2.0 times the tensile strength.
Under a normal atmosphere, the durable strength of processed and annealed titanium and titanium alloys is (0.5-0.65) times the tensile strength. When performing 107 fatigue tests in the notched state (Kt=3.9), the endurance strength of annealed Ti-6Al-4V is 0.2 times the tensile strength.
The hardness of the highest purity grade of processed industrial pure titanium is usually less than 120HB, and the hardness of processed titanium of other purity is 200-295HB. The hardness of pure titanium castings is 200-220HB. The hardness value of titanium alloy in the annealed state is 32-38HRC, which is equivalent to 298-349HB. The hardness of as-cast Ti-5Al-2.5Sn and Ti-6Al-4V alloys is 320HB, and the hardness of Ti-6Al-4V castings with low gap impurities is 310HB.
The tensile elastic modulus of industrial pure titanium is 105-109GPa, and the tensile elastic modulus of most titanium alloys is 110-120GPa in the returned state. The age-hardened titanium alloy has a slightly higher tensile elastic modulus than in the annealed state, and the compressive elastic modulus is equal to or greater than the tensile elastic modulus. Although the stiffness of titanium and titanium alloys is much higher than that of aluminum and aluminum alloys, they are only 55% of iron. The specific elastic modulus of titanium alloy is comparable to that of aluminum alloy, second only to beryllium, molybdenum, and some high-temperature alloys.
The torsion or shear modulus of industrial pure titanium is 46 GPa, and the shear modulus of titanium alloy is 43-51 GPa.
In order to increase the strength of the titanium alloy, increasing the content of interstitial elements will have a harmful effect on the impact resistance and fracture toughness of the alloy. According to the different types and states of titanium alloys, the Charpy notched impact strength of industrial pure titanium is 15-54J/cm2, and the cast state is 4-10J/cm2. The impact strength of titanium alloy in the annealed state is 13-25.8J/cm2, which is slightly lower in the aging state. The Charpy V-notch impact strength of as-cast Ti-5Al-2.5Sn alloy is 10J/cm2, and that of Ti-6Al-4V alloy is 20-23J/cm2. The lower the oxygen content of titanium alloy processing materials, the higher this value.
Many titanium alloys have very high fracture toughness, or in other words, titanium alloys have good crack propagation resistance. The annealed Ti-6Al-4V alloy is a material with excellent toughness. When the notch concentration factor Kt=25.4mm, the ratio of notched tensile strength to non-notched tensile strength is greater than 1.
Titanium alloys can maintain certain properties at high temperatures. General industrial titanium alloys can maintain their useful properties at a temperature of 540°C, but they can only be used for short periods of time, and the temperature range for long-term use is 450-480°C. At present, a titanium alloy for use at a temperature of 600°C has been developed. As a missile material, titanium alloy can be used for a long time at a temperature of 540°C, and it can also be used for a short time at a temperature of 760°C.
Titanium and titanium alloy materials can still maintain their original mechanical properties at low and ultra-low temperatures. As the temperature decreases, the strength of titanium and titanium alloy materials continues to increase, while the ductility gradually deteriorates. Many annealed titanium alloy materials also have sufficient ductility and fracture toughness at -195.5°C. The Ti-5Al-2.5Sn alloy with very few interstitial elements can be used at a temperature of -252.7°C. The ratio of its notched tensile strength to non-notched tensile strength is 0.95-1.15 at a temperature of -25.7°C.
Liquid oxygen, liquid hydrogen, and liquid fluorine are important propellants in missiles and space devices. The low-temperature properties of the materials used to make low-temperature gas containers and low-temperature structural parts are very important. When the microstructure is equiaxed and the content of interstitial elements (oxygen, nitrogen, hydrogen, etc.) is very low, the ductility of the titanium alloy is still above 5%. Most titanium alloys have poor ductility at -252.7°C, while the elongation of Ti-6Al-4V alloy can reach 12%.
medical titanium sheet Titanium Aluminum Sputtering Target Grade 12 Titanium Tube titanium sheet metal
medical titanium sheet Titanium Aluminum Sputtering Target Grade 12 Titanium Tube titanium sheet metal
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