In the cutting of TC4 titanium plate, the common process flow and content are described as follows:
- (1) If it is semi-automatic cutting, then 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, taking care not to reverse the order.
- (2) The cutting parameters should be appropriate, and should be reasonably determined according to the thickness of the titanium plate, etc., so as to obtain a good cutting effect.
- (3) Check whether the cutting gas is unobstructed. If there is 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 can facilitate the blowing of slag.
- (5) The distance between the cutting nozzle and the surface of the titanium plate should be appropriate, too close or too far is not good.
- (6) The preheating of the titanium plate should be sufficient to avoid affecting the cutting process.
- (7) If cutting workpieces of different sizes, then small pieces should be cut first, then large pieces.
Titanium alloy plate
Titanium plate manufacturer data shows that titanium is a new type of metal. The performance of titanium is related to the content of impurities such as carbon, nitrogen, hydrogen, and oxygen. The purity of the most pure titanium iodide impurity does not exceed 0.1%, but its strength is low and its 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 / (mK), tensile strength σb = 539MPa, elongation δ = 25%, shrinkage at section 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 steels. Therefore, the specific strength (strength / density) of the titanium alloy is much greater than other metal structural materials. See Table 7-1, which can produce parts and components with high unit strength, good rigidity and light weight. At present, titanium alloys are used for aircraft engine components, skeletons, skins, fasteners and landing gear.
- (2) High thermal strength
The use temperature is several hundred degrees higher than that of aluminum alloy. It can still maintain the required strength at medium temperature. It can work for a long time at a temperature of 450 to 500 ℃. These two types of titanium alloys are still very high in the range of 150 ℃ to 500 ℃. Specific strength, while the specific strength of aluminum alloy at 150 ℃ significantly decreased. The working temperature of titanium alloy can reach 500 ℃, aluminum alloy is below 200 ℃.
- (3) Good corrosion resistance
Titanium alloys work in humid atmosphere and seawater media, and their corrosion resistance is far superior to stainless steel; they are particularly resistant to pitting, acid corrosion, and stress corrosion; organic materials such as alkali, chloride, chlorine, nitric acid, and sulfuric acid Etc. have excellent corrosion resistance. But titanium has poor corrosion resistance to media with reducing oxygen and chromium salts.
- (4) Good low temperature performance
Titanium alloy can still maintain its mechanical properties under low temperature and ultra-low temperature. Titanium alloys with good low temperature performance and extremely low interstitial elements, such as TA7, can maintain a certain plasticity at -253 ℃. Therefore, titanium alloy is also an important low-temperature structural material.
- (5) Great chemical activity
Titanium has a large chemical activity and produces a strong chemical reaction with O, N, H, CO, CO2, water vapor, ammonia gas, etc. in the atmosphere. When the carbon content is greater than 0.2%, hard TiC will be formed in the titanium alloy; when the temperature is high, the TiN hard surface layer will be formed when it interacts with N; above 600 ℃, titanium absorbs oxygen to form a hardened layer with high hardness ; Increased hydrogen content will also form a brittle layer. The depth of the hard and brittle surface layer produced by absorbing gas can reach 0.1 ～ 0.15mm, and the degree of hardening is 20% ～ 30%. Titanium also has a large chemical affinity, and is prone to adhere to friction surfaces.
- (6) Small thermal conductivity and small elastic modulus
Titanium’s thermal conductivity λ = 15.24W / (m.K) is about 1/4 of nickel, 1/5 of iron, 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. The springback of the processed surface during cutting is very large, which is about 2 to 3 of stainless steel Times, causing violent friction, adhesion, adhesive wear on the flank of the tool.