In the cutting of TC4 titanium plate and titanium alloy plate<<https://www.yunchtitanium.com/gr2-astm-b-f67-titanium-plates-ti6al4v-eli, the common process flow and content are described as follows:
(1) If it is semi-automatic cutting, the guide rail should be placed on the plane of the titanium plate, and then the cutting machine should be placed on the guide rail. Note that the order cannot be reversed.
(2) The cutting parameters should be appropriate and should be reasonably determined according to the thickness of the titanium plate, so as to obtain a good cutting effect.
(3) Check whether the gas of the cutting nozzle is unblocked. If there is any blockage, it should be dredged in time.
(4) Before cutting, the surface of the titanium plate should be cleaned and a certain space should be left, which is conducive to the blowing out of the slag.
(5) The distance between the cutting nozzle and the surface of the titanium plate should be appropriate, it is not good if it is too close or too far.
(6) The preheating of the titanium plate should be sufficient so as not to affect the cutting process.
(7) If cutting workpieces of different sizes, the small pieces should be cut first, and then the large pieces.
The data of titanium plate manufacturers show that titanium is a new type of metal. The performance of titanium is related to the content of carbon, nitrogen, hydrogen, oxygen, and other impurities. The purest titanium iodide impurity content does not exceed 0.1%, but its strength is low and plasticity is high. . The properties of 99.5% industrial pure titanium are density ρ=4.5g/cm3, melting point 1725℃, thermal conductivity λ=15.24W/(m. K), tensile strength σb=539MPa, elongation δ=25%, section shrinkage Rate ψ=25%, elastic modulus E=1.078×105MPa, hardness HB195.
(1) High specific strength
The density of titanium alloy is generally about 4.5g/cm3, which is only 60% of steel. The strength of pure titanium is close to that of ordinary steel. Some high-strength titanium alloys exceed the strength of many alloy structural sheets of steel. Therefore, the specific strength (strength/density) of titanium alloy is much higher than that of other metal structural materials, see Table 7-1, and parts and components with high unit strength, good rigidity, and lightweight can be produced. At present, titanium alloys are used in aircraft engine components, skeletons, skins, fasteners, and landing gear.
(2) High thermal strength
The operating temperature is several hundred degrees higher than that of aluminum alloys, and the required strength can still be maintained at moderate temperatures, and it can work for a long time at a temperature of 450 to 500 °C. The specific strength of aluminum alloy decreases significantly at 150 °C. The working temperature of titanium alloy can reach 500 ℃, and the working temperature of aluminum alloy is below 200 ℃.
(3) Good corrosion resistance
Titanium alloy works in a humid atmosphere and seawater medium, and its corrosion resistance is much better than stainless steel; its resistance to pitting corrosion, acid corrosion, and stress corrosion is particularly strong; it is resistant to alkali, chloride, chlorine, organic substances, nitric acid, sulfuric acid, etc. have excellent corrosion resistance. However, titanium has poor corrosion resistance to media with reducing oxygen and chromium salts.
(4) Good low-temperature performance
Titanium alloys can still maintain their mechanical properties at low and ultra-low temperatures. Titanium alloys<<https://www.yunchtitanium.com/gr2-astm-b-f67-titanium-plates-ti6al4v-eli with good low-temperature performance and extremely low interstitial elements, such as TA7, can maintain certain plasticity at -253 °C. Therefore, titanium alloy is also an important low-temperature structural material.
(5) High chemical activity
Titanium has high chemical activity and produces strong chemical reactions with O, N, H, CO, CO2, water vapor, ammonia, etc. in the atmosphere. When the carbon content is more than 0.2%, hard TiC will be formed in the titanium alloy; when the temperature is high, a hard surface layer of TiN will also be formed when the temperature is high; when the temperature is above 600 ℃, titanium absorbs oxygen to form a hardened layer with high hardness; Increased hydrogen content will also form an embrittlement layer. The depth of the hard and brittle surface layer produced by absorbing gas can reach 0.1-0.15mm, and the hardening degree is 20%-30%. The chemical affinity of titanium is also large, and it is easy to adhere to the friction surface.
(6) Small thermal conductivity and small elastic modulus
The thermal conductivity of titanium λ=15.24W/(m. K) is about 1/4 of nickel, 1/5 of iron, and 1/14 of aluminum, and the thermal conductivity of various titanium alloys is about 50% lower than that of titanium. The elastic modulus of titanium alloy is about 1/2 of that of steel, so its rigidity is poor and it is easy to deform. It is not suitable to make slender rods and thin-walled parts. times, resulting in severe friction, adhesion and bond wear on the flank of the tool.